HomeMy WebLinkAboutAPA3164G
601
C2
A2
no.73-27
An Inventory of Wildlife Habitat
of WKHMackenzie Valley and the Northern Yukon.
Prepared by the
Special Habitat Evaluation Group
Canadian Wildlife Service
Department of the Environment
G. H. Watson
w. H. Prescott
E. A. de Bock
J. w. Nolan
M. c. Dennington
H. J. Poston
Dr. I. G. Stirling
for the
Environmental-Social Program
Northern Pipelines
December 1973
2&T 1 7 1974
Environmental-Social Committee
Northern Pipelines,
Information Canada
Cat. No. R72-12273
Task Force on Northern Oil Development
Report No. 73-27 QS-1536-000-EE-Al
The data for this report were obtained as a result
of investigations carried out under the Environmental-
Social Program, Northern Pipelines, of the Task Force
on Northern Oil Development, Government of Canada.
While the studies and investigations were initiated to
provide information necessary for the assessment of
pipeline proposals, the knowledge gained is equally
useful in planning and assessing highways and other
development projects.
PAGE
1. GENERAL SUMMARY
2. INTRODUCTION 10
2. 1 General Nature and Scope of Study 11
2.2 The Objectives of the study 12
2. 3 General Relationships to Pipeline Development 13
2. 4 Organization of the Report 13
3. STUDY AREA 14
4. GENERAL METHODS 16
4.1 Accumulation of Available Information 16
4. 2 Aerial Photo Interpretation and Unit Mapping 16
4.3 Field surveys and Data Collection 17
4.4 Analysis and Final Mapping 17
5. RESULTS
5. 1 Moose
5.1.1 Introduction
5.1.2 Methods
5.1.3 Results and Discussion
5.1.4 Conclusions
5.1.5 Implications and Recommendations
5.1.5.1 Implications
5.1.5.2 Recommendations
5.1.5.3 Conclusions
19
19
21
28
29
29
35
37
5o 2 caribou
5o2.1 caribou other than the Porcupine Herd
5.2.1.1 Introduction
5. 2. 1. 2 Study Area
5. 2. 1. 3 Methods
5.2.1.4 Results and Discussion
5o2.1.5 Conclusions
5 2. 1o 6 Implications
5.2o2 Porcupine Herd of Barren-ground Caribou
5.2.2.1
5.2.2.2
5.2.2.3
5o2o2.4
5.2.2.5
5.3 Dall Sheep
Introduction
Methods
Results and Discussion
Speculations on Impact
of the Pipeline
Recommendations
5.3. 1 Introduction
5. 3. 2 Methods
5.3.3 Results and Discussion
5. 3. 4 Conclusions
5.3o5 Speculaticns on Impact
5o3.6 Recommendations
5.4 Grizzly Bears
5.4. 1 Introduction
5 o 4 o 2 Methods
5. 4. 3 Results and Discussion
PAGE
41
42
42
43
46
47
47
49
50
63
65
69
69
71
75
76
77
81
81
83
5.5
5.4.4 Conclusions
5.4.5 Speculations on Impact -Grizzly Bear
5.4.6 Speculations on Impact -Black Bear
5.4.7 Recommendations -Grizzly and Black Bears
Arctic Fox
5.5.1 Introduction
5.5.2 Methods
5. 5. 3 Results and Discussion
5.5.4 Conclusions
5.5.5 Speculations on Impact
5.5.6 Recommendations
5.6 Muskrat and Beaver
5 • 6. 1 In trod uc t ion
5.6.2 Methods
5. 6. 3 Results
5.6.4 Discussion
5.6.5 Potential Construction Impact
5.7 Waterfowl
5.7.1 Introduction
5.7.2 Methods
5. 7. 3 Results and Discussion
5.7.4 Implications and Recommendations
PAGE
84
85
85
86
89
89
91
92
92
93
96
97
99
99
100
109
110
112
113
5. 8 Raptors
5.9 Polar Bears
5.9.1 Introduction
5.9.2 Discussion
5.9.3 Implications
5.9.4 Recommendations
6. GENERAL DISCUSSION
7. GENERAL CONCLUSIONS
8. IMPLICATIONS AND RECOMMENDATIONS
9. NEEDS FOR FURTHER STUDY
9. 1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
Moose
caribou
Dall Sheep
Grizzly Bears
Arctic Fox
Muskrat and Beaver
Waterfowl
Raptors
10. REFERENCES
10.1 Literature Cited
10.2 General References
11. APPENDICES
11.1 List of Scientific Names of Plants
Referred to in this Report, Including
Accompanying Atlases
11.2 Speculations on Impact of Various
Pipeline Construction Activities
12. ATLASES* (in 7 separate volumes):
12.1 Atlas of Arctic Fox Habitat Maps
(7 maps + descriptions)
12.2 Atlas of Beaver and Muskrat Habitat
PAGE
122
125
126
127
127
129
131
136
138
138
139
140
140
141
141
142
144
146
148
150
* A limited number of these atlases are available for
purchase from the Canadian Wildlife Service, Western Region,
1110 -10025 Jasper Avenue, Edmonton, Alberta TSJ 186.
Maps (30 maps + descriptions)
12.3 Atlas of caribou Range Maps
(25 maps + descriptions)
12.4 Atlas of Porcupine Caribou
Herd Movement Maps (22 maps + description
of herd)
12.5 Atlas of Dall Sheep and Grizzly Bear
Habitat Maps (25 maps + descriptions)
12.6 Atlas of Moose Habitat Maps
(33 maps + descriptions)
12.7 Atlas of Waterfowl Habitat Maps
(33 maps + descriptions)
1. GENERAL SU~MAFY
In late 1971, the Canadian Wildlife Service Special
Habitat Evaluation Group began an extensive, preliminary
inventory, which included wildlife assessments on large
areas within, and adjacent to proposed gas and oil pipeline
corridors in Canada's Western Arctic. (Note: The term
"corridor" is used in this report for convenience to
represent the general location of possible pipeline routes,
but it is recognized that no corridor per se has yet been
recognized or approved.) The inventory was timely, as plans
for development of the North became headline news, and
details of wildlife populations were for the most part
little known.
The wildlife species included for study were selected
primarily on the basis of social values and feasibility of
short-term inventory, with some consideration directed to
the susceptibility of the species to disturbance and some to
esthetic values. Animals represented in the mapping series
are: caribou, Moose, Arctic Fox, Dall Sheep, Grizzly Bear,
Beaver, Muskrat, and waterfowl.
It is to be noted that the aim of the study has been a
habitat inventory and not an inventory of wildlife
populations. Because of the vastness of the area, the
seasonal movements of various species, the natural
fluctuations in populations numbers, and observation
difficulties, a successful population inventory would not
have been feasible in one calendar year. The ultimate goal
has therefore been the production of a series of maps
defining relative importance of landscape or habitat units.
This series is a prerequisite to an assessment of potential
problems related to any major developments.
1. 1 Moose
Moose are widespread throughout the Mackenzie River
Valley and northern Yukon. They are severely restricted in
winter, however, to three main land forms. These are, in
order of importance, river valleys, wetland complexes and
upland slopes. The class ratings of areas depend primarily
on the food species and the amount of shelter present. The
importance of areas, on the other hand, depends on the
quality and quantity of habitat, the abundance of animals
and the location of the area (See Section 5.1.2).
Class 1 areas are primarily found in river valleys. Not
2
only are they very important, but, because they are somewhat
restrictive in winter, the high moose populations usually
found in them are extremely vulnerable. Development of any
kind in or around most of these areas will inevitably lead
to a population reduction.
Class 2 areas are more diversified in habitat types.
The Class 2 areas in river valleys may be rated almost as
critical as Class 1 areas. In other situations, however,
they tend to be larger and more dependent on disturbances.
In these cases, they are not so critical.
Class 3 areas are also important in the river valley
sites, where they are usually confined to a narrow band of
riparian vegetation. The importance of Class 3 areas is more
dependent on location than quality. This class becomes much
more critical to moose in isolated and northern areas,
especially along the Arctic Coast. Although they occur in
very low numbers, moose there are entirely dependent in
winter on the narrow riparian growths on the banks of
streams winding through barren tundra. The other habitat
types in this class, uplands and wetland complexes, are not
often critical because they usually occur in large blocks,
and the suitable habitat and moose populations are usually
widespread.
Moose are very dependent on habitat disturbance for
their existence. Flooding along fastTflowing mountain rivers
and fires create almost all the available habitat,
especially in the southern portion of the study area. In the
north the shallow active layer over the permafrost limits
the growth of browse species to along the river channels. In
this case the habitat would appear to be held permanently in
an early seral stage.
Interference with moose populations can be alleviated
to a great extent through proper route selection. Avoidance
of major wintering areas and important travel routes will
provide the best solution. Problems resulting after
construction from FUblic Fressures are unavoidable, and will
require wise management programs.
1.2 caribou
There are three sub-species of caribou found in
Northern canada the woodland caribou, R~gif~£ !~~g~§
£s£lEQ!!L the barren-ground caribou, R~gifer targgg,!!§
grQgn!srrQ~£.!!2L and the reindeer, li~si!~ !~!!g.!!§
sibiricus.
-----~--
3
All three sub-species are located on the study area.
Woodland caribou, probably the most widespread, are year-
round residents. They can be found on both sides of the
Mackenzie River as far north as the treeline on the east
side, and to Arctic Red River on the west. There are two
major groups of barren-ground caribou involved. one group,
known as the Bluenose herd, is found east of the Mackenzie
River and do~s not usually come into the Valley during its
seasonal movements. The other important group, the Porcupine
herd, has been termed the ''International Herd" since its
yearly movements involve parts of northeastern Alaska as
well as the northern half of the Yukon. This caribou herd
traditionally moves north and northwest into Alaska every
spring. Basic routes are used in their spring migration and
variations of these routes are followed in their fall
southward migration. Wintering areas which have been used by
the Porcupine herd vary from tundra plains on the Arctic
Coast to the extremely mountainous areas south of the Peel
River.
The remaining caribou may be
woodland caribou, feral reindeer
species. They apparently summer just
Lakes and winter around and to
Travaillant Lake.
barren-ground
or a mixture
south of the
the north and
caribou,
of sub-
Eskimo
east of
It has been
which seem to
caribou: staging
river crossings.
possible to define four particular areas
held special significance for migratory
areas, calving areas, mineral licks, and
Movements and chronology of movements have been
documented in detail for the Porcupine herd but not for the
other groups and sub-species. All observations have
indicated the variability and unpredictability of caribou
movements. Much more data are needed on distribution,
abundance, and movement behavior before accurate predictions
can be made on impact.
Taking the variability of migration chronology and
movement patterns into account, there are several
possibilities for catastrophic pipeline effects on caribou.
Obstruction and disruption of migratory behavior,
particularly in spring, aircraft harassment, increased
hunting pressures, noise disturbance from compressor
stations, and deflection cf migratory movements along berms
or right-of-ways must all be considered definite
possibilities. once the exact routing of the pipeline is
known, preventive measures that are now being studied should
reduce most of these problems.
4
1.3 Dall Sheep
All Dall sheep habitat is situated west of the
Mackenzie River. Habitat quality is not unduly limited as
might be expected in more northerly latitudes.
The most important sections of Dall sheep range are
wintering areas, lambing areas, and mineral licks. Winter
range is considered the mcst important habitat and sheep are
often concentrated on these ranges. Little is known about
the location and characteristics of lambing areas. Ewes are
known to favor very rugged habitat, and occasionally
concentrate during the lambing period. Sheep, especially
ewes and lambs, tend to concentrate around mineral licks,
sometimes in large numbers, during the spring and summer.
Four major poFulations of Dall sheep occur in the study
area: the Nahanni, Ram, Yohin-Liard group; the Mackenzie
Mountains group; the Richardson Mountains group; and the
British Mountains group.
Dall sheep are very susceptible to disturbance. Since
sheep are concentrated in favorable areas in winter, and may
concentrate around mineral licks and in lambing areas, these
areas become much more critical.
It is unlikely that sheep will directly suffer from
loss of habitat. Indirect disturbances, such as aircraft
disturbance, excessive noise, fill and rock removal, and
human activity are likely to be much greater problems. To
keep the impact on sheep at a minimum, these factors must be
closely controlled.
1.4 Grizzly Bear
Grizzly bear distribution along the pipeline corridor
varies from almost nil in some southern sections to high
densities in the northern and mountainous regions.
Distribution and abundance of grizzly bear seems to depend
more on availability of food than on specific habitat types.
Information collected in the northern Yukon suggests that
adult male bears have a very large home range, and aFpear to
follow the migrating barren-ground caribou. Landform,
topography, vegetative type and apparent food sources were
considered in delineating and describing grizzly bear
habitat.
Den sites are an important factor in considering
5
grizzly bear habitat, and records indicate long-term use of
individual dens. Disturbance or elimination of denning sites
could have a drastic effect on the bear population in some
locations. The amount of bear disturbance and the occurrence
of man-bear interaction will probably increase as
construction programs move into habitat supporting higher
numbers of grizzlies. Adequate precautions and contingency
plans should greatly reduce the probability of problems
developing.
1. 5 Arctic Fox
Arctic fox range is restricted to the arctic tundra
regions of the study area. The main criterion used in
assessing arctic fox habitat was the relative density of
maternal dens on potential fox range.
The greatest concentration of arctic fox dens was found
in the Herschel Island map area. Dens occurred on a variety
of sites including sand dunes, frost heaves, and on the
brims of river, lake, and stream banks. Nearly all den sites
were in a position to command a good view of the surrounding
area, and all were near fresh water.
Foxes prefer to den in areas of fine, well-sorted silt,
sand or gravel. Extraction of granular material for pipeline
construction could result in habitat degradation by
reduction of denning sites. High density denning areas, such
as those on the Herschel Island mapsheet, would be
particularly vulnerable. This is especially so, as it is
known that dens are used for long periods of time.
Harassment by aircraft, heavy equipment or explosives
could result in females abandoning their young. Therefore,
caution should be exercised in the area of dens during the
whelping and denning period from mid-May to early September.
Arctic foxes often scavenge during winter periods and are
easily drawn to raw garbage. During the winter, hungry foxes
show little fear of man, and will most certainly be
attracted to camps situated in the area. This is not
desirable, as foxes are known carriers of rabies.
1.6 Beaver and Muskrat
The most extensive
muskrat habitat occur
Mackenzie River and the
lacustrine basins along
areas of better quality beaver and
in the deltaic complex of the lower
thermokarst lakes within glacial
the Ramparts River west of Fort Good
6
Hope, the Brackett River northeast of Fort Norman, MacKay
Creek south of Fort Norman, and west of the Mackenzie River
at Camsell Bend.
Lakes of the Old Crow Flats and several less extensive
basins along the Porcupine River provide very favorable
muskrat habitat but are of only minor importance to beaver.
Drumlinized till deposits, between Fort McPherson and Martin
House, provide a combination of drainage confinement and
shoreline stability that teaver prefer for dam construction.
In the more southern regions, good beaver habitat is
found within stream systems on the gently sloping flanks of
several large plateaus. Very extensive organic overburden in
the headwaters and excellent deciduous shrub cover along the
meandering mainstem channels contribute to the overall value
of these systems. Harris Creek north of Fort Simpson, the
south fork of the Martin River and the Matou River near
Sibbeston Lake, and the unnamed stream emptying into the
northwest side of Trout Lake, all fall within the above
category.
Two other areas of good quality beaver habitat worthy
of mention are the Tetcela River, occupying a broad u-shaped
intermontane basin on the west side of the Sibbeston Lake
mapsheet and the deltaic region on the lower Kakisa River.
The relative value of muskrat and beaver habitat within
the study area is dependant on a variety of physical and
vegetational features. These features are a reflection of
interacting and continuing geomorphic processes. Predicting
changes in habitat which could be precipitated by
construction activity necessarily implies a knowledge of
both direct and indirect influences of such activity. The
former may be readily quantified, within the construction
zone, in terms of pond and lake basins drained, streams
diverted etc. The latter, often involving much more subtle
but widespread changes, cannot be readily quantified, or
predicted, through preliminary habitat evaluation programs.
For the present, a brief and speculative summary is included
to relate probable activities to specific habitat types. The
magnitude and overall implications of habitat alteration
must be considered on an individual basis at each point of
intersection on given construction routes.
1.7 Waterfowl
Waterfowl inhabit northern regions annually from May
through September.
7
The Mackenzie River, including islands, is a most
important and critical spring migration pathway whereon tens
of thousands of geese, ducks, and swans congregate, moving
gradually northward with signs of breakup. On arrival at
their destinations, pairs disperse to breed on the countless
lakes, ponds, and streams of boreal and tundra regions. In
mid-summer, moulting flocks of flightless adult birds
congregate along coastal and large inland waters. With
approach of fall, small and large concentrations of
waterfowl prepare for the long flight southward. The most
spectacular concentrations form on the North Slope and
estuarine areas off the Mackenzie Delta where several
hundred thousand birds, mostly snow geese, condition
themselves until freeze-up when they leave.
Many comflexities of wetland habitats are related to
quality, reflected in utilization by breeding waterfowl • In
this inventory, emphasis has been placed on categorizing
habitats and tabulating an assessment of the relative
importance to the waterfowl. Extensive areas of notably good
waterfowl habitat are: the Old Crow Flats, the Mackenzie
Delta, the Tuktoyaktuk Peninsula and the dense wetlands
adjacent to the Kakisa River. Other less extensive areas are
equally, if not more, important on a per/acre basis,
especially basins situated in alluvial sediments on
floodplains and deltas. Generally, however, the northern
wetlands are predoninantly of low quality.
construction influences related to waterfowl and
wetland habitats are expected to be: loss and degradation of
habitat; disturbance to waterfowl; and a potential localized
over-harvest from hunting. The magnitude of environmental
alteration on localized areas must be ascertained at points
of intersection of construction routes and waterfowl
habitat. To accommcdate these requirements, this inventory
will be most valuable. Further additional studies are now in
progress.
1.8 Rare and Endangered Species -Raptors
The raptors referred to in this report are the
peregrine falcon, gyrfalccn, osprey, bald eagle and golden
eagle. Although all five species are not equally rare or
endangered, they may all be influenced by the construction
of a pipeline. The construction phase of the proposed
pipeline should not seriously affect raptors in general;
however, it will contribute to the ever-increasing reduction
of their numbers. Since raptors are wilderness species, the
area actually affected by pipeline construction may be much
8
greater than that in the immediate vicinity of the line.
Nesting sites as far away as 1 or 2 miles or more en each
side of any construction activity, including camps,
airports, haul roads, blasting, etc., may be influenced. All
nest sites along the proposed route have not yet been
located, so the actual number of raptors that will be
involved is not known.
Although construction disturbance will likely be
temporary, its effects may be permanent. At least two of the
raptor species, the peregrine falcon and bald eagle, are
known to be declining. Once displaced from traditional
nesting sites, there is no assurance that they will return.
The anticipated increased human pressures will also
extend the area that will be affected. The effect of human
presence and activities on raptors varies with season.
Disturbance during the establishment of territories in early
April or May, during the egg-laying and incubation period
from May to June, and during the flightless period of the
young from June to August may lead to abandonment or
destruction of the nest and young. The threat of illegal egg
collecting, irresponsible shooting of young and adult
raptors and the robbing of young from nests for falconry
will accompany increased human access and activity
associated with the construction and operation of the
pipeline.
The
into the
raptors.
increased introduction of pollutants and chemicals
northern environment could seriously affect
In summary, raptors are very sensitive to disturbance
and have the potential of becoming the wildlife species most
seriously affected by northern development. careful
selection of route and associated development location can
keep the influence of pipeline construction at a minimum.
1.9 Ra~e and Endangered Species -Polar Bears
Polar bear conflicts are expected with pipeline
activities. They are known to occur within the study area
along the coast of the Beaufort Sea from west of Herschel
Island, Y.T. to Baillie Island, N.W.T. Polar bears tend to
concentrate near these islands because the open leads that
occur in the offshore ice during the winter and spring are
used by seals. Evidence indicates a shift away from Herschel
Island since activity has taken place there in 1972.
9
Excessive noise from vehicular activity during the
winter period is likely to be disruptive to coastal
wildlife, particularly polar bears. The storage of fuel near
the edge of the sea also raises a considerable threat to the
marine ecosystem.
The outcome of man-polar bear encounters is extremely
unpredictable. Many polar bears have little fear of man.
Every attempt should be made to avoid attracting bears to
camps or work areas and contingency plans must be ready if
the bears do appear.
10
2. INTRODUCTION
Wildlife, although a simple word, encompasses a large
variety of animals, of which each species has its own
distinctive life cycle and habitat requirements. It is
difficult to imagine a greater contrast than that between
the sedentary beaver, living in its own small aquatic
habitat, and the migratory birds, travelling thousands of
miles twice a year to reach their nesting sites in the
Arctic and to return to their wintering areas far south of
the Canadian border. Equally great contrasts exist between
the solitary grizzly bears, with territories of hundreds of
square miles, and the dense herds of barren-ground caribou,
which at certain concentration points, travel shoulder to
shoulder in tens of thousands. And yet, beneath these
obvious differences there is a common bond, the joint use of
the same huge ecosystem, which unifies these animals. Beaver
and waterfowl, although their life cycles are very
different, occupy the same aquatic habitats; grizzly bear
and barren-ground caribou have a relationship of predator to
prey as well as occupying the same biotype.
The land is as egually complex as the wildlife it
supports, and within the study area several major land
systems exist. In the northwest, the coastal zone of the
Arctic Ocean is prcminent. The low, shelving coast grades
gently into the undulating hills of the North Slope.
Offshore, gravel and sandbars, sheltered bays and lagoons
are common. South from the coastal zone, the hills of the
North Slope, treeless and of a gently rolling nature, merge
with the slopes cf the British Mountains, with their steep
valleys containing swift flowing rivers and streams. Still
farther south, the dense wetland formations of the Old Crow
Flats form a unique landscape feature.
The valley of the Mackenzie River is far from uniform.
Distinctive features of interest in our assessment include
its delta -by far the largest river delta in the Canadian
Arctic supporting, because of its dynamic hydrological
regime and its fertile silt, a productive array of plant and
animal life. The Delta alone is some 5,000 square miles in
area, a mosaic of estuarine flats, levees, river channels,
marshes, meadows and lakes. Other distinctive features of
the River, as one proceeds south, are its many islands,
densely covered with white spruce and willow, the large,
numerous lakes of the floodplain, and the abrupt escarpments
marking the valley edges. Farther south the riverbanks form
unstable slopes, and important tributaries add their flow to
the system. Changes in vegetation become apparent; low
spruces, willows and birches in scattered groups on the
11
poorly drained soils give way to dense stands of greater
height in the valleys, and the bare uplands are increasingly
encroached upon by the rather monotonous forests of the
Boreal Forest Zone.
2.1 General Nature and Scope of Study
At the start of the project, in December 1971, it was
realized that only one calendar year was available to
complete a certain stage of the investigations. In view of
the limited time, the paucity of relevant existing
information, and past experience with mapping projects of
large areas such as the Canada Land Inventory, it was
decided to embark upon a mapping project of wildlife
habitat. As a consequence, the main part of this report
consists of a series of maps or 'Atlases• showing wildlife
habitat units for a single species, or for a group of
species combined. In general, four classes of habitat
quality are shown. It is difficult to give a general
description of "quality". The class ratings are based on the
capability to produce wildlife, the present habitat
conditions and the presence of animals; but the weight of
these criteria differs with the rating systems used for the
various species of wildlife.
It should be pointed out that the goal of the study is
a habitat inventory, and not an inventory of wildlife
populations. Due to the vastness of the area, the seasonal
movements of certain animals and the difficulty to observe
animals masked by a cover of vegetation, a population
inventory would have been impossible to carry out
successfully in such a short period. The Canadian Wildlife
Service formed a Special Habitat Evaluation Group in
December 1971, consisting of seventeen new employees. This
group consisted of four teams, each of which was charged
with a certain responsibility. At the start, the four teams
were as follows:
!Ifii£ fQ~L Qriz~lY Be~£ ~Q~ Q~ll Sh§~£
R. Glasrud1, Biologist
J. Nolan, B. Goski, G. Wilde 1, technicians
~~~Y~£ ~ng ~Y§~£~1
M. Dennington, Biologist
B. Johnson, H. Stelfox, c. Paley 1, technicians
tleft during 1972
12
W. Prescott, Biologist
G. Erickson, D. Smith, L. Walton, s. Harrison, z technicians
H. Poston, Biologist
A. Doberstein, s. Barber, technicians
E. de Bock, Biologist (under contract)
Dr. Ian Stirling (advisor)
G. Watson
Other workers gave valuable advice and although it is
not possible to name each individual, we would like to thank
Dr. T. Barry, V. Hawley, Dr. A. Pearson, E. Telfer, B. Fyfe,
B. Nowosad and personnel of Renewable Resources Consulting
services Ltd., L.G. L. Ltd. Environmental Research
Associates, Williams Bros. Ltd., Inter-disciplinary Systems
Ltd., and last but not least, the residents of the
communities within the study area who gave us valuable
advice and assistance. The drafting, atlas lay-out and art
work was capably undertaken by B. Chubb.
2.2 The Objectives of the Study
The objectives of the study were:
a) to construct a map series of a scale of 1:250,000 showing
habitat units for the following species:
Moose
caribou, ether than the Porcupine herd
Dall sheep and Grizzly bear
Arctic fox
Beaver and Muskrat
Waterfowl
2transferred during 1972
13
b) to map, on the same scale, the movements of the Porcupine
herd of barren-ground caribou.
c) to present information on rare and endangered species
such as falcons and polar bears.
d) to forecast, on the basis of present knowledge and with
the best judgement available, the possible effects of
pipeline construction on wildlife and wildlife habitat.
2.3 The General Relationships to Pipeline Development
The general relationships of the study to concerns
about pipeline development are direct. The wildlife habitat
map series shows units of habitat, and by plotting the
proposed pipeline routes, identification of areas of
possible conflict can be made. However, it is not possible,
on the basis of present knowledge, to gauge with accuracy
1hg gegr~g of effect such pipeline construction would have
on wildlife and its habitat.
2.4 Organization cf the Report
This report ccnsists of two main sections:
a) a general section
b) a specialized section containing habitat maps and
accompanying descriptions for each species or species group
in booklet form called Atlases.
14
3. STUDY AREA
Any final pipeline route or transportation corridor
will occupy a very small land area in terms of the North. It
was necessary, however, to include a wide belt of terrain in
order to be prepared for any variations from the originally
proposed route and to identify important wildlife habitat
units which might be affected by the construction of a
pipeline and its aftermath, even though they may be miles
away from the actual construction sites.
Complete mapsheets at a scale of 1:250,000 were used as
base maps. A total of 33 mapsheets were designated as
containing part of the proposed pipeline route or those that
could be influenced by the pipeline or construction of the
pipeline. The gecgraphical area covered by this study
occupies approximately 151,000 square miles.
The number of maps investigated depended on the species
and their range; e.g. arctic fox were found only along the
Arctic coast; only seven mapsheets were used.
,.....study
...._.area
Figure 1. The area of inventory.
15
16
4. GENERAL METHODS
Considerations of the vast area included for study,
combined with a cne-year time constraint, demanded habitat
classification systems general enough to allow evaluation by
use of aerial photos and geological and forest cover maps,
yet specific enough to facilitate identification of the
components serving to limit or enhance any given wildlife
habitat type. The former requirement was met through initial
grouping of generically related landforms and;or associated
wetlands; the latter through aerial surveys of habitat and
associated wildlife populations.
4.1 Accumulation of Available Information
Initial preparation of
specific literature review,
reports.
the
and
inventory
compilation
began with a
of existing
Valuable insight was gained from lectures, and
discussions with canadian Wildlife Service personnel
experienced in northern biological research. Dr. A. Pearson,
Dr. T. Barry, Dr. N. Simmons, V. Hawley, Dr. J. Kelsall, R.
Fyfe and E. Telfer all contributed information and ideas
beneficial to the study. The factors to be considered became
clearer due to this background research.
The Arctic Ecology Series supplied general species
distribution material which assisted in identification of
knowledge gaps. Similarly, the recently published Arctic
Land Use Information Series, cws reports, and miscellaneous
publications were reviewed. For most species, only general
data were available.
We are most grateful to the Northwest Project Study
Group and Gas Arctic Systems for supplying preliminary and
interim reports of 1971 field studies on northern wildlife.
4.2 Aerial Photo Interpretation and Unit Mapping
Using all available information on landforms, surficial
geology, and vegetation, basic homogeneous land or wetland
habitat units were outlined on 1:250,000 NTS topcgraphic
base maps. Primarily, aerial photographs and topographic
maps were utilized, but use was also made of surficial
geology data provided by the Geological survey of canada and
forest classification Frovided by Forest Management
Institute whenever available.
17
Each habitat unit was number~d for reference. It must
be assumed that gradient zones exist between habitat
classes, and delineation lines are only approximate.
4.3 Field Surveys and Data Collection
Ski-wheel-and float-equipped Cessna-185 aircraft were
used for most survey flights. Bell-206 helicopters were used
for low-level surveys in rugged mountainous terrain, and for
surveys requiring ground inspections not available from
fixed-wing aircraft. A De Havilland Beaver, STOL equipped
Cessna-185 and a Piper Aztec c were used occasionally. The
De Havilland Beaver and Piper Aztec c were found to be
generally unsatisfactory for survey work. The De Havilland
Beaver was excessively noisy and had poor visibility while
the Piper Aztec C was too fast and had poor visibility. Both
models of Cessna and the Bell-206 possessed the desired
range, manoeuverability and visibility.
Almost all observation flights undertaken at speeds of
90-110 miles per hour and altitudes of 100 to 500 feet, were
carried out with a pilot and a 2-man crew. One man acted as
the observer and the ether as a navigator. Both pilot and
navigator could usually find time to make observations. The
navigator would call out checkpoints at intervals and the
observer would then describe the habitat or wildlife species
numbers. Every effort was made to obtain unbiased visual
information on all designated habitat units. The in-flight
data were recorded on Sony (TC-40) cassette tape recorders.
Each observation of mammals, birds, or animal sign was
plotted as a numbered checkpoint on 1:25C,OOO topographic
maps. Data were transcribed from tape records to notes.
To accompany the verbal field observations, a large
number of 35 mm. slides were taken for later reference and
comparison.
4.4 Analysis and Final Mapping
Data accumulated in the previous stages were gathered
together and analysed. The preliminary unit boundaries on
the 1:250,000 NTS base maps were adjusted, then the units
were classified into a 4-class system taking all the data
obtained into account. An explanation of the classification
criteria has been included in this report and the Atlases.
The Atlases, one for each species group, contain
18
general descriptions of mapsheet features and more detailed
map narratives for each mapsheet. The narratives describe
the habitat units or types used by that particular species.
19
5. RESULTS
5. 1 Moose
5.1.1 Introduction
Moose were known to be found throughout the Mackenzie
River system. They form an important food source for the
native people and their hides are used for clothing, etc.
Although a considerable amount was known about their general
distribution, little was known or recorded about specific
areas. It was this specific information that was necessary
to determine the ef£ects of pipeline construction.
The main objective of the 1972 field season was to
carry out an inventory of moose habitat along a possible gas
pipeline corridor that would run along the Mackenzie River
valley from the Alberta -N.W.T. border to the Mackenzie
Delta and through the Northern Yukon to the Alaska border.
This inventory would allow the classification of land or
habitat map units, using a 4-class system. Although habitat
mapping was the prime objective, present moose distribution
would also be deteimined. The ultimate goal was to produce a
set of maps that would indicate critical and sensitive areas
and allow an assessment of potential problems related to
pipeline construction.
Since moose aie restricted or tend to concentrate in
"favorable" areas in the winter, it was our initial
intention to gain more information on these aieas of
concentration. It would be in these areas that moose would
be most affected by any disturbance. If moose concentrate to
the same extent that some southern studies have indicated,
disturbance in wintering areas could adversely affect the
moose population of the surrounding area as well. We began
this survey with three basic presumptions:
1. moose are capable of inhabiting all types of available
habitat at vaiious times cf the year,
2. moose concentrate in favorable areas in winter,
3. these "favorable" areas will be most sensitive to
disturbance.
5.1.2 Methods
20
The mapping and data gathering was undertaken in four
overlapping "stages". These were as follows:
1. Aerial Photo Interpretation and Land Unit Mapping
Using all available information on landform, surficial
geology and vegetation, basic homogeneous land or habitat
units were outlined on the 1:250,000 topographic base maps.
Each habitat unit was numbered for reference and a basic
data sheet was compiled on each.
2. Moose Range Aerial Surveys -Winter
Aerial reconnaissance flights using fixed-wing aircraft
were carried out to obtain the data necessary to determine
preliminary habitat classification of the land units. All
information obtained was recorded on data description
sheets. When animals or tracks were observed, detailed
descriptions of the habitat in their immediate vicinity were
also recorded.
The winter reconnaissance surveys were begun February
1, 1972 and were completed by April 30, 1972. Due to
fluctuations in manpower and weather conditions it was not
possible to survey some areas during the winter. Data for
these areas were obtained later in the summer.
3. Moose Range Aerial surveys -Summer
The winter surveys were followed up by summer
observation flights to areas with insufficient or no data.
Although habitat descriptions were the prime objective of
the summer flights, observations on spring summer
dispersal and distribution were also made. The same
techniques as used in the winter surveys were used during
the summer.
4. Final Map Preparation
The data obtained in the previously described stages
were gathered together and analyzed. All unit boundaries
were checked and revised. All units were then classified in
a 4-class system taking all the data obtained into account.
The Four-Class System used is as follows:
Class 1 -Good combinations of shelter and food species,
especially-Willow, are present, with the food species at the
21
proper successional stage to provide and maintain abundant
food supplies. Landform and vegetation combine to provide
good quality shelter from the Arctic winds. There usually
was considerable evidence of animals present. Relatively few
obvious limitations were present other than those applicable
to the whole region such as short growing season and extreme
temperatures.
Class 2 -K~if combinations of shelter and food species
occur with some obvious additional limitations, e.g. poor
selection of food species and exposure to wind -through
lack of adequate shelter, etc. Moose populations can still
be high but are usually mere spread out.
Class 3 -Generally £22~ combinations of shelter and food
species are present in these areas, sometimes with a lack of
shelter altogether. Food species can vary from sparse and/or
patchy, to very abundant. The former situation is usually
accompanied by an over-abundance of shelter and the latter
by little or no shelter. Moose numbers are usually
relatively low and the animals are more spread out.
Very small areas of Class 1 or 2 habitat have been
combined and placed in Class 3. Their small size and their
ability to support only small numbers of moose reduce their
ability to support only small numbers of moose reduce their
relative importance. Some areas of unrealized potential are
also placed in this class, e.g. the Mackenzie Delta.
Class 4 -Areas having in§igni1i£SD! 2f nil moose habitat
are placed in this class. Known and potential summer range
have also been placed in this class.
Maps have been prepared using the above classification.
These are accompanied by a general description of the
mapsheet area and a detailed description of each habitat
unit.
5.1.3 Results and Discussion
The habitat classification maps and accompanying
descriptions are included in 'Atlas -Moose•.
From the beginning it became obvious that the winter
range of moose was considerably more restricted than was
previously indicated. In fact, throughout most of the study
area the actual land area utilized by moose during the
winter was so proportionately small, especially to the
north, that it takes on a much more critical nature.
22
During the winter 1971-1972, above average snowfalls
occurred, forcing moose to utilize the most favorable
wintering areas available. At no time however, did the
recorded snow depths exceed the limits established in
southern studies that would severely restrict moose
movements. The covering of food sources, low shrubs, etc.,
normally available in summer apparently forced the animals
to concentrate in areas where abundant food supplies were
available above the snow. This was generally in three
habitat types; along river or stream valleys, around lake
margins or in 5 to 50-year-old burns on upland sites.
The value of these types is dependent on the production
of riparian and/or early successional vegetation such as
willows, birch, and alder. Frequent flooding and ice-
scouring action maintain the riparian vegetation, and fires
play an important role in maintaining the important early
stage of succession on most upland sites. The instability of
some valley sides contributes to the maintenance of sera!
vegetation in some areas, especially those facing south.
Fires play a significant role in the creation of moose
habitat. Except foi floodplain areas, almost all present
moose habitat has been the result of fire. The time of year
and the intensity cf the fire, as well as the qualities of
the soils, interact in the determination of the type of
regeneiation. Burns that regenerate primarily in deciduous
shrubs are very important to moose and are frequently used
both winter and summer. The predominant climax stage of
black spruce -lichen is not suited for moose and is usually
avoided.
Beavers play a minor role in creating moose habitat.
The building of ponds and the cutting of poplar, aspen,
birch and willow help to re-establish the low and high shrub
layer. The resulting small food patches amongst otherwise
mature forest provide ideal winter habitat. This situation
usually occurs along smaller slow-moving streams and is more
common in the southern part of the study area.
Habitat Types
giv~£ y~ll~Y§ can be separated into two tyfes. The
first, (a) consists of slew-moving streams and rivers which
usually have broad valleys. The stream may be meandering or
linear but must be subject to frequent flooding cr other
disturbance to be attractive to moose. Flooding, often
assisted by fire, maintains the riparian vegetation along
the banks and oxbows. In areas of permafrost, the active
layer goes much deeper alcng rivers. Species like poplar,
23
aspen and white spruce most often grow under these
conditions, with the latter being the common climax. The
amount of deciduous shrubs such as willow and alder that
occur depends on the extent of recent disturbance. The
second, (b) consists of faster flowing rivers which usually
have deep, narrow valleys, a braided channel and a flat
floodplain. Annual flooding and ice action keeFs the
vegetation on the floodplain at an early successional stage.
These valleys quite often have a typical arrangement of
vegetation. There may be no vegetation on the many exposed
gravel bars in the stream itself, while on the shore, and on
some of the larger more stable gravel bars, willow and alder
thrive. The active layer is deep and moisture is plentiful.
The pH of the water is net usually as acid as in the slower
moving streams. On the more stable areas flooded but not
often damaged by ice cr water, stands of poplar occur,
usually bounded by white spruce. Fires rarely influence this
type of habitat because of the steep valley walls, the
abundant moisture, and the braided nature of the streambed
often breaking the vegetation into isolated islands. The
steep sides of the valley often contribute to food
production, for, unless they are pure bedrock, they are
usually unstable and readily eroded, providing a favorable
base for the establishment of early successional shrubs.
jetlan£ £2IDE!~~~ are areas or units containing many
lakes and po~ds. There are many varieties of wetland
complexes -some poorly drained and some better drained
types, such as flat lcwland, hilly upland, acid bog and
sedge-marsh types. Moose prefer those wetland complexes that
have a rich deciduous shrub component. Shrubby shorelines
generally occur around relatively well-drained sedge-marsh
lakes. The shrub component is maintained by frequent
flooding or by fires. The vegetation around the lakes quite
often resembles that along the braided fast-flowing streams
described above, consisting of deciduous shrub, poplar and
white spruce. The surrounding upland vegetation, if
favorable, adds to the significance of the complex -the
better drained the upland the more deciduous species occur.
Emergent aquatic vegetation is often utilized in late
winter. Equisetum and sedges are also dug up and eaten. The
lakes and ponds are also used during the summer for feeding,
when aquatics are plentiful, and for cooling or relief from
flies.
Q£!~g site§ are sometimes used by moose for wintering
although this type is not commonly preferred. Upland
wintering areas almost always occur on a slope, and are the
result of fires. Being on a slope they are relatively well-
drained, favoring regeneration to deciduous species, willow,
24
alder, birch and sometimes poplar. These areas are
frequently cut by many small streams which are quite often
an important component of the winter habitat. In flatter
areas the vegetation in the stream vicinity, being on a more
moist site, tends not to burn as readily, leaving islands of
mature vegetation. on steeper slopes the streams are often
deeply eroded, again providing refugia from fires. These
islands of vegetation or small vegetated valleys provide
important shelter from the Arctic winds that would be
particularly severe in an otherwise open upland burn.
Table 1 gives a breakdown of the various habitat units
into types and classes, beth burned and unburned, as well as
giving a comparison between habitat to the north of Fort
Good Hope and that to the south.
Class 1 areas are the most critical for moose and are
most susceptible to any form of human disturbance. Most
Class 1 areas are found in river valley situations and they
are highly dependent on the riparian features of the
vegetation. Less than a third have been influenced by fires.
Since moose are often confined within these areas by
topographic features in winter, they can become very
vulnerable. The high populations that now winter in most of
these areas may be the entire population from a surrounding
region 5 to 10 times as large as the wintering area itself.
It is extremely imFortant that development of any kind be
restricted in these Class 1 areas or their immediate
vicinity since disturbance could be almost as destructive as
habitat loss.
Class 2 areas are more diversified in habitat types.
Fast-flowing, braided river valleys are the most common. In
most cases these are similar to Class 1 areas but are
usually smaller with less extensive riparian components.
Being smaller and more restrictive, they may be rated as
important locally to moose survival as any Class 1 areas,
although less productive.
The valleys of slow-moving meandering type streams and
wetland complexes are also important Class 2 habitat types.
They too are largely dependent on the riparian vegetation
for their importance but water level fluctuations are not
the only prime factor in their creation. Fires have
influenced a majority of these types and extensive areas of
deciduous regeneration have resulted. The fire influence is
usually temporary and the non-riparian components are
unlikely to remain at the optimum successional level for any
long period.
Table 1. Distribution of habitat units over various landforms
River Valleys Lake Complexes Uplands and Slopes
Meandering Braided
Habitat
Types Burned Unburned Burned Unburned Burned Unburned Burned Unburned
-
Classes
*North
Class 1 -2 -2
Class 2 1 8 -17 2 2
Class 3 44 2 25 -7 3 2 2
*South
Class 1 9 10 2 13 2
Class 2 9 1 1 16 8 2 9 1
Class 3 35 26 29 3 15 24 19 45
Total Area
Class 1 9 12 2 15 2
Class 2 10 9 1 33 10 4 9 1
Class 3 79 30 54 3 22 27 21 47
*North refers to those mapsheet areas north and west of Fort Good Hope and Ontaratue River.
South refers to the remainder of the study area. N
\.1"1
26
Upland Class 2 sites are almost exclusively the result
of fires. Slightly sloping, better drained areas tend to
regenerate deciduous shrubs and trees, particularly along
small drainages. Again the optimum successional stage is not
long lasting and the importance of these areas is usually
temporary. More permanency occurs on mountainous and
northern sites where the influence of higher elevations and
more severe climate keeps vegetation in the shrub stage
considerably lcnger.
The majority of Class 3 areas are found along slow-
moving meandering streams. Although heavily influenced by
fires, the imFortance of most of these areas is due to small
strips of riparian vegetation along the streams. Fires
enlarge or rejuvenate this strip but on the whole are
relatively ineffective at enhancing the quality. Many
valleys associated with fast-moving braided streams have
also been classed as Class 3. Most of these cccur in
mountainous areas and are Class 3 because of lack of shelter
species. They tend to be composed of small strips of
favorable food species, mostly willow and alder, in an
otherwise open tundra or alpine situation.
Wetland complexes and upland sites also contribute a
large portion of the Class 3 areas. Most are affected by
fires. Many of the fires are old and the areas are now in a
sub-climax stage of mature deciduous or mixed forest cover
particularly on the hilltops and the better drained areas.
The shrub comFonent is abundant in the scattered openings in
this type and near any water bodies or streams. Such areas
usually occur in considerably larger blocks than most other
classes and types, e.g. the Mackenzie Delta, the Old Crow
Flats, the Rampart~ Flats.
The importance of the Class 3 areas depends more on the
location than the quality. Even low quality habitat becomes
extremely important if it is the only available habitat for
many miles around. This applies to the river valley~ along
the Arctic coast. They provide year-round habitat to only a
small number of animals but any destruction of habitat or
disturbance in these areas, especially in winter, could
result in extirpating moo~e locally.
Distribution
Moose are found throughout the study area, being more
abundant and wide~pread in the south but occurring right to
the Arctic coast. Moose are seen during the summer in almost
every type of habitat from stream bottom to mountain top.
They are, however, somewhat more restricted in the northern
27
tundra and are seldom seen very far from the riparian
vegetation along the streams and rivers either in winter or
summer.
The river valleys and associated floodplains frovide
the best year-round habitat available, although they are
particularly important in winter. The islands in the
Mackenzie River, for example, are heavily utilized in the
winter. The broad willow flats found there are maintained at
the optimum successional stage by frequent flooding and ice
action. The river valley itself provides some shelter and
nearby dense stands cf conifers are available should better
shelter be required.
The optimum sections of the Mackenzie, as described
above, generally occur downstream from the mouths of major
tributaries. Between these sections, the black spruce upland
extends to the edges of the steep banks. The river is
usually narrow and islands are absent. Flood damage often is
minimal under these circumstances and the riparian
vegetation favored by moose is generally not present.
The fast-flowing actively meandering or braided streams
and rivers on the west side of the Mackenzie also provide
optimum winter habitat. The annual torrents of meltwater and
ice scour the banks and floodplains, keeping the riparian
vegetation ccntinually replaced. Often these areas are
heavily utilized year-round except during the spring flood
period. They are especially important in the north. The lack
of shelter in the tundra permafrost regions has lowered the
relative value and classification of valleys in those
regions but their importance actually increases because of
the absence of alternative sites.
Rivers on the east side of the Mackenzie River and in
the south of the study area do not drain mountainous areas.
They are slower flcwing and are often associated with poorly
drained upland boggy situations. Disturbance frcm the
rivers, i.e. flooding, etc., is usually minimal. Their value
is increased by fires depending on the existing drainage
conditions. Better drained areas that have been burned
usually regenerate with deciduous trees and shrubs, while
poorer drained bogs often fail to regenerate or come back
slowly with scattered and stunted black spruce.
The value of upland sites to moose is also dependent on
fires and drainage patterns. The better drained upland sites
quite often regenerate tc birch, poplar or pine. Almost all
upland sites useful to moose are the result of fires. Many
were classed as unburned in Table 1 because they were
28
presently in a sub-climax stage of mature deciduous or pine
forest. Very often the openness of such stands result in
some tolerant shrub species being available. The significant
upland sites, none of which were rated Class 1, are more
common south of the continuous permafrost regions. Only four
marginal upland areas were found in the continuous
permafrost zone north of Fort Good Hope.
The majority of the useful wetland complexes were also
found in the south. They are most often related to major
drainage systems although some occur in isolated upland
areas. Only two are classed as class 1 and both are the
result of fire disturbance. The majority of the wetlands are
marginal because of the relatively small shrub component.
They are important, however, because of the large area many
cover, and the large portion of the moose population they
support.
5.1.4 Conclusions
Moose are widespread throughout the Mackenzie River
Valley and northern Yukon. They are severely restricted in
winter, however, to three ~ain habitat types. These are, in
order of importance, river valleys, wetland complexes, and
upland slopes. The classification of an area depends
primarily on the food species and the amount of shelter
present. The importance of an area, on the other hand,
depends on the quality and quantity of habitat, the
abundance of animals and the location of the area.
Class 1 areas are primarily found in river valleys. Not
only are they very important but, because they are
restrictive, the high moose populations found in them are
extremely vulnerable. Development of any kind in or around
most of these areas will inevitably lead to a population
reduction.
Class 2 areas are more diversified in habitat types.
The Class 2 areas in river valleys may be rated almost as
critical as Class 1 areas. In other situations, however,
they tend to be larger and more dependent on disturbances.
In these cases, they are net so critical.
Class 3 areas are also important in the river valley
sites where they are usually confined to the narrow tand of
riparian vegetation. The importance of Class 3 areas is more
dependent on location than quality. This class becomes much
29
more critical to moose in isolated and northern areas,
especially along the arctic coast. Although they occur in
very lew numbers, the moose there are entirely dependent in
winter on the narrow riparian bands winding through barren
tundra. The other habitat types in this class, uplands and
wetland complexes, are not often critical because they
usually occur in large blocks and the suitable habitat and
moose populations are usually widespread.
Moose are very dependent on habitat disturbance for
their existance. Flooding along fast-flowing mountain rivers
and fires create almost all the available habitat,
especially in the southern portion of the study area. In the
north, the shallow active layer over the permafrost limits
the growth of browse species to along the river channels. In
this case the habitat would appear to be held permanently in
an early seral stage.
5.1.5 General Implications and Recommendations
5.1.5. 1 Implications
There are three main areas of concern for moose which
would result from the construction of a gas pipeline from
Alaska up the Mackenzie Valley to Alberta. These are:
a) habitat alteration, both destruction and
b) obstruction or disruption of normal
movement behavior, and,
c) increased human Fressures.
a. Habitat Alteration
enhancement,
activity and
Destruction cf moose habitat could vary from the
crossing of a moose wintering area at right angles by the
pipeline right-of-way to the establishment of a 5,000 man
camp, a large borrow pit or a 5,000 foot airstrip in the
center of such an area. Since moose may be restricted in
winter to a small portion of their summer range, major
destruction within this area could severely reduce or
eliminate a local population. It is assumed the Froposed
pipeline right-of-way will be 100 to 120 feet wide. This may
represent a considerable portion of some habitat types. If
the pipeline right-of-way follows one side of a stream
valley through a moose wintering area for some distance it
could effectively reduce the available habitat in that area
and potentially reduce the local moose population by half or
30
more.
The removal of gravel could also provide considerable
impact on moose. In some places, gravel sources will be
borrow pits and in others stream bottoms will be the only
source. Borrow pits may not be located in areas presently
heavily utilized by moose. The location of a borrow Fit in a
wintering area would probably destroy some habitat. Removal
of gravel from stream bottoms could have much more
disastrous effects. Riparian vegetation normally growing in
these situations is extremely important to wintering moose.
Willows, alders and poplars are commonly found here and are
all important moose foods. Stripping gravel from the stream
bottoms usually means the removal of any vegetation. Quite
likely, all the available gravel would be removed. The
replacement of gravel and re-establishment of the riparian
vegetation could take a very long time, possibly forever,
depending on the changes effected in the river course and
bed.
It is unlikely that airstrips will be located in areas
heavily used by moose, but if they are, the large area
required will severely influence moose. The noise of the
aircraft and associated human activity would have additive
indirect effects.
Generally, di~ect destruction of habitat can be fairly
accurately predicted and eliminated or reduced substantially
in the planning stages. Also, effects may be temporary if
related just to the const~uction stage.
Re-establishment in the disturbed area depends on the
type and level of continuing disturbance associated with the
operation and maintenance stages, as well as the rate and
extent of revegetation of the disturbed area. Since
vegetation growth would have to be controlled along the
right-of-way to facilitate surveillance and maintenance,
this area would likely remain lost to moose as habitat. The
use of herbicides for this purpose would have questionable
effects on a browse-eating species like moose. The
revegetation of excavated, disturbed and gravelled areas
will result in increased forage production. This may have
mixed effects on moose.
As a positive value, revegetation will increase, at
least temporarily, the available summer forage. The plants,
mostly grasses, will be fertilized to improve growth, and
establishment will provide a greatly increased quantity and
quality of nutrients.
31
The availability of fertilized green forage might
attract animals closer to human habitation or access. The
animals then become much more vulnerable to hunters and
vehicle collisons, especially if a road is associated with
the pipeline.
Unseasonal availability of fertilized green forage may
also result in a delay in the necessary adaptive changes in
the micro-organism complex of these ruminants which enable
the animal to utilize the highly fibrous winter forage.
b. Obstruction of Normal Behavior Patterns
Although moose are not considered migratory, they have
been found to undergo seasonal movements of a moderately
extensive nature (Edwards, et al, 1956). Any above ground
portions of a 48-inch pipeline would provide a definite
barrier to moose movement. Even partial obstruction would
reduce efficient utilization of their habitat and would
perhaps isolate necessary components of their range. Both
these effects would mean a reduction in moose numbers.
A buried pipeline or a road would probably have only a
minor direct effect, if any, individually, but the two
combined could very likely have an additive effect. The two
would provide not only a physical barrier but, due to the
presence of vehicles and hunters on the road, any crossing
by animals would be further discouraged.
So far, moose have not been documented as moving any
distances in the Mackenzie Valley. However, the populations
wintering on the islands undoubtedly move on and off these
islands from the surrounding area, since no moose were
recorded on them during summer investigations.
There are fewer available wintering areas on the east
side of the Mackenzie than on the west side. It seems
reasonable to speculate that it is primarily the moose
summering on the east side that move to the main valley and
the islands in the Mackenzie to winter. If this is so, then
the animals must cross the area of the proposed pipeline at
least twice each year. Interruption of this movement could
have considerable local effects.
Data collected so far in the northern Yukon indicate
that in this area there might be movements of considerable
proportions taking place seasonally. With the observations
of large fluctuations in moose numbers on the Old Crow Flats
over the year, a movement onto the Flats in summer and then
back in to the surrounding river valleys, particularly in
32
the mountains to the northr in winterr seems likely. The
broad river valleys of the Firth River and tributaries of
the Porcupine and Old Crow rivers hold relatively large
numbers of moose in winter. Fortunatelyr if this is the
pattern of movement that does take place, neither of the
presently proposed pipeline alternatives in the northern
Yukon should interfere to any great extent.
Other factors that might influence movements are: the
presence of odors cf the pipe itself, of escaping gasesr or
from compressing machinery; the presence of sounds of
compressor stations, campsr vehicles and blasting, the
presence and use of winter haul roads from the Mackenzie
River to the construction sites and snow accumulation caused
by drifting along the pipeline right-of-way or berm or by
plowing on adjacent roads. The plowed area may also be
utilized as a movement corridor. This should not be harmful
unless vehicle traffic is common along the road or animals
are led away from traditional travel routes. Vehicle traffic
can in itself discourage movement. If the animals are
attracted to the haul roads by revegetation practices or by
plowed areas, particularly in winters of deep snowr
collisions may become a problem. In areas where gravel is
scarce or lacking and revegetation is not effective in
insulating the disturbed surfacer the disturbed area might
meltr forming an impassible moat in the summer. This has
commonly occurred on some seismic operations over continuous
permafrost, especially in already marshy areas.
The open ditch during construction could provide an
effective trap. Normal associated construction activity
should keep moose away, but in thickly wooded areas moose
may suddenly appear and try to jump the 6 to 8 foot ditch.
Adults may make it but calves certainly could not. Animals
falling into the ditch would be killed or injured orr if
not, would provide the difficult problem of getting them
out.
Disturbances associated with pipeline construction,
operation and maintenance activities such as increased human
activity, the operation of heavy construction equipment,
blasting and the use of all-terrain vehicles and low-flying
aircraft, especially helicoptersr could all disrupt normal
behavior patternsr greatly increase physiological stress and
force animals from their normal activity areas. Assuming the
surrounding area is at capacity, then a reduction in local
populations could result.
Fortunately most of these disturbances would only be
related to the construction phase and are short-term, but
33
the use of low-flying aircraft wiil undoubtedly continue
during the operation and maintenance stages. Aircraft,
particularly heliccpters, are extremely disturbing to moose.
The process of getting closer for picture-taking or hazing
although only foi shoit periods, may have severe
consequences on animals already under the extreme stresses
of an Arctic winter. An animal chased for even short
distances at -30° to -soo F., can very easily develop
pulmonary emphysema which may lead to pneumonia and death.
Death may not occur until weeks later. Running an animal for
only 20 minutes may be enough to double the daily energy
requirement, putting additional pressure on the habitat
(Geist, 1971). Any additional stress on pregnant cows,
particularly late in the winter, could mean loss of the calf
or calves. There is also the possibility that an animal
pursued by an aircraft could very easily, during its panicky
flight, severely injure itself on obstacles, such as the
sharp crusts of the snow. Fortunately moose are solitary
animals and the effects of this disturbance are usually very
local, but moose wintering in the more open northern
situations, along the North Slope, for example, cculd be
seriously affected since they are more conspicuous and are
normally under more severe physiological stress. As the
number of industrial and private aircraft increases in the
north this problem will increase.
The use of all-terrain vehicles, snowmobiles,
bombadiers, and hovercraft should have little impact if used
strictly for the work of construction or maintenance. It is
the unrestricted use for recreation that could have serious
effects. Their impact is much like that described for
aircraft.
The construction and maintenance of roads and airstrips
accompanying the pipeline, as well as the increased use of
all-terrain vehicles and aircraft, poses probably one of the
greatest problems of all for moose. Increased access will
lead to greatly increased hunting pressure, particularly
along the pipeline route and accompanying roads and
airstrips and around settlements and camps. If moose do move
seasonally to and from wintering areas, they would become
more vulnerable to hunters when they cross roads and the
pipeline rights•of-way. Moose may learn to avoid these
moose-hunter encounters by avoiding the road. Thus the
combination of road and pipeline might not in themselves
obstruct movement, but the addition of hunters could very
well be enough to at least reduce moose movement across
them. This would have the effect of maintaining the
disturbance factor of the pipeline long after construction
would have ceased.
34
c. Increased Human Pressures
The expected increase in human population will have two
major effects: increased encroachment into critical winter
habitat by settlements, development, etc., and increased
hunting pressure by residents and non-residents.
The tremendous number of workers that will be employed
on pipeline construction (some predictions are as high as
15,000) will undoubtedly have some influence on the
surrounding wildlife populations. Pipeline workers will or
can be closely controlled (firearms will be restricted,
etc.) at least on the job, and they will be unlikely to have
much free time. Expanding local populations will undcubtedly
create a substantial increase in the high hunting fressure
that now exists. Already large areas of low or nil moose
populations exist in potentially good habitat around many
northern communities, particularly those with large native
populations. These "moose vacuums" will grow as the hunting
population grows, and as the better methods of travel, for
example, snowmobiles, aircraft and automobiles, becoue more
readily available. The areas most influenced now will feel
even greater pressure and the more remote areas will become
more accessible. Non-resident hunting, at present exerting
low pressure, will undoubtedly increase greatly as access
increases. The native population presents the greatest
problems. Most natives depend heavily on wild meat for
winter food and they apFlY greatest hunting pressures when
the moose are most vulnerable. Fortunately the use cf dogs
is not as popular as in the past and the requirement of wild
meat as dog food has lessened considerably. The trend away
from trapping, and relocation in and dependance on the
settlements has likely reduced hunting pressures in some
places, but hunting pressures have increased around the
settlements as a result.
Not only will the local wildlife populations be in
danger from increased access leading to increased hunting
pressure, but any hunting along or near the pipeline could
lead to indirect or accidental damage to the pipeline
itself. Exposed valves and other equipment as well as the
line itself could well pose the same type of target as power
pole insulators do in the south.
Increased huwan poFulations will likely result in more
man-caused wildfires. Fires have varying results on
different wildlife populations and in different
circumstances. Fer moose, the result is generally an
improvement in habitat, at least in the 5 to 30 years
following the fire. Moose prefer at least part of their
35
range in an early successional stage when it provides the
large amounts of deciduous browse species that moose require
to survive. In fact, it is possible that the widespread
occurrence of fires could have been responsible for, or at
least hastened, the northern extension in moose range.
It should also be noted that the potential increase in
the number of fires would lead to more intensive fire
suppression efforts. This would definitely be required along
the pipeline itself and near settlements because of the
danger to installations and human life. Just what tyFe of a
balance between the occurrence and control of fires is
desirable will require careful thought and much more
investigation. Increased fire suppression will likely lead
to a reduction in available moose habitat and consequently a
reduction in FOpulation.
Although the magnitude of the problem of pollutants and
chemicals is difficult to predict, loss of habitat will
inevitably result from their misuse. Some potential
pollutants are: sulfur dioxide from the exhaust gas, pump
lubricants, flushing fluids, herbicides and pesticides.
Research is underway on some aspects of these possible side
effects for northern areas.
The use of herbicides to maintain the pipeline right-
of-way and pesticides to control insects around camps should
be strictly ccntrolled. The breakdown rate of any chemical
would be much slower in the cold arctic environment and the
effects of these chemicals on animal systems under the
stresses of an arctic winter could be much greater than
further south. Extreme caution should be taken in
introducing any such chemicals into the arctic ecosystem.
5.1.5.2 Recommendations
a. Habitat Destruction or Alteration
General route selection can alleviate most of the
impact of the pipeline construction itself. There are very
few important moose wintering areas located alcng the
presently proposed pipeline route on the east side of the
Mackenzie River. The few areas that are involved, mostly
located along the tributaries of the Mackenzie River, will
be crossed at right angles, destroying or altering very
little of the areas.
The effects of indirect habitat destruction caused by
the location of facilities like haul roads, airstrips,
36
gravel pits and construction camps will vary with different
locations. In general, haul roads should not be located
along river valleys since most wildlife winter activity is
located there. Net only would the more important wildlife
habitat be saved but animal-vehicle contacts would be fewer
and many ercsion problems alleviated, if valley locations
were avoided.
The removal of gravel from streams and river valleys
could effectively remove the riparian vegetation so
necessary and attractive to moose. Revegetation would
probably be slow in the northern climate. As little gravel
as possible should be taken from streams, and if taken, the
location should be carefully selected. The large gravel
pads, many roads and other habitat alterations resulting
from the location of the extremely large constructicn camps
envisioned, means that locations must be carefully selected.
Miscalculations could have disastrous local ecological
effects.
The reaction of moose to revegetation attempts cannot
be predicted. Careful monitoring of the situation will be
necessary so that if it proves to have a negative value,
correctional measures can be immediately undertaken.
Experiments with revegetation species that are not
attractive to ungulates should be undertaken.
b. Obstruction of Movements
Knowledge on the behavior of moose following alteration
in habitat is very limited and there is insufficient
research done to enable reliable recommendations to be made
on any adaptions in design of the pipeline to overcome any
problem should it occur. Stipulations restricting times of
construction may be required if this becomes an important
problem. Hunting may have to be controlled in problem areas,
possibly by establishing a no-hunting zone alcng the
pipeline right-of-way during movement periods.
As to the effects of the other factors involved
odors, sounds, differential snow accumulation, winter haul
roads, location of gravel sources and location of campsites
a better knowledge of moose behavior and distribution is
needed. It can be fredicted that should any of these factors
or their location prove disturbing, the local moose
population will be reduced.
Attempts will be
movement patterns in
Recommendations will
made to document distribution and
potential problem areas in 1973.
be made at the time on methods to
37
alleviate any specific prcblems that may develop.
The effects of low-flying aircraft are not so difficult
to foresee but will be difficult to control. To reduce this
problem, all attempts to prevent flying lower than 500 feet
above the ground should be made, particularly during the
winter and spring periods. Not only should perscnnel be
informed that harassing wildlife is illegal but the physical
and physiological damage that could occur to the animal
should be stressed. Using an aircraft to hunt is illegal,
except for transportation to the hunting area. The companies
involved can and should be enforcing these types of
restrictions and held responsible for any violations.
c. Increased Human Pressures
Problems invclved with increased human pressures can
only be solved by greater monitoring of the situation and
the implementation and enforcement of more restrictive game
regulations when and if they are needed. A good program of
public education on wildlife conservation in the Northwest
Territories would help tremendously.
Although potential problems can be anticipated from
southern experience it will be necessary to identify and
study each. More life history research is needed.
Information such as annual production, normal carrying
capacity of the range, age composition of the herd and
normal mortality is required before adequate management
policies can be formulated.
Once new regulations and management plans are proposed,
much effort must be placed on enforcing them. An increased
staff of enforcement personnel will be needed.
The principal impact on moose will be from increased
access as a result of pipeline construction, accompanying
roads and the increasing local human population. It may
become necessary tc restrict hunting and/or all vehicle
traffic in vulnerable areas.
5.1.5.3 Conclusions
Although the pipeline right-of-way will mainly be
chosen to meet engineering and construction requirements it
must also be chosen to serve the greatest possible
combination of interests of the public and the environment.
Interference with moose populations can be alleviated to a
great extent through proper route selection. Avoidance of
38
major wintering areas and important travel routes will
provide the best solution. Problems resulting after
construction from public fressures are unavoidable and will
require wise management programs to control. Moose are one
of the most impcrtant wildlife species economically and
socially in the north. With proper precautions it can remain
so.
39
~ble 2. A summary of the expected effects upon moose of the activities associated
with the construction of a gas pipeline.
Activity
Pipeline right-of-
way
Location of camps
Remova 1 of sand and
vavel along streams
Increased fires
Berms and road grades
Noise-creating
activities -construction
vehicles, blasting, etc.
Reclamation procedures
Ditching
Harassment from any
source
Potential Effects
Direct destruction of wintering
habitat
Direct loss of wintering habitat
The removal of riparian vegetation
reduces the quality of mose moose
wintering areas and therefore the
carrying capacity
The immediate loss of wintering
habitat. Long-term results
often favorable to moose
-These may create travel lanes
changing movement direction
during seasonal movements
-Snow may drift beside elevated
roads or berms (or may be plowed
up) obstructing movements
Animals may be forced into
less favorable habitat by
disturbance
Moose may be attracted to
these areas where they are
more vulnerable and away from
traditional habitat
Animals may be diverted from
normal movement patterns or
may fa 11 in
In mid-winter the daily energy
expenditure of the harassed
animals may exceed the energy
present in the total forage
available, thus placing the
animal in a negative energy
balance. If this is compensated
for in increased food consumption
by the animals there would be an
over a 11 increase in pressures of
animals on their food resources
with a reduction in carrying
capacity of the habitat.
Magnitude
Light
Light
Severe
Severe
Light
Light
Light
Light
Light
Severe
Table 2. Cont'd.
Activity
Aircraft use on
pipeline project
Human Activity
Potential Effects
Although moose can be disturbed
by aircraft at any time during
the year, disturbance would be
particularly serious at calving
time or in winter when the
animals might be pressed by
food shortages.
Most wild animals avoid humans,
therefore they may be forced into
inferior habitat
Increased access to important
wintering areas may increase
the harvest of moose beyond
the amount desirable.
40
Magnitude
Moderate
Light
Moderate
41
5. 2 CARIBOU
5.2.1 Caribou other than the Porcupine herd
5.2.1.1 Introduction
There are two and possibly three sub-species of caribou
to be found in the vicinity of the proposed gas Fipeline
route along the Mackenzie Valley. Woodland caribou, ~gngi!~I
1~~~QQ]§ ~ribQ~3, and barren-ground caribou, ~angiter
1~£~n~~ g£Qg~la~gic~3, are the species of major concern.
The third sub-species is reindeer, g~ngifei 1~~~2
sihi£i£Q§3, escaped over the years from the Canada Reindeer
Project. The barren-ground caribou of the Porcupine herd
(also ~~ng!f~ !~dU§ g~o~nl~ndiCU§) are not included in
this section of the report since they are reported on
separately.
The woodland caribou is the most widespread of the sub-
species within the Mackenzie River Valley. These animals are
found from the Alberta herder to just south of Inuvik along
both sides of the Mackenzie River.
Most of the ~arren-ground caribou, other than the
Porcupine herd, belong to what is collectively called the
Bluenose herd. They were named after a large lake in the
vicinity of their summer ~ange. Estimates of this herd range
widely from 20,000 to 150,000 animals. The range in
estimates is undoubtedly due to the variety in survey
efforts and techniques involved and the vast winter range
available and used by this group.
The third sub-species, suspected to be in large part
escaped reindeer or offspring of escaped reindeer, number
from 1,000 to 2,000 animals and range between the Husky
Lakes in summer and the Travaillant Lake -Iroquois River
area in winter.
Because of the difficulty in separating groups and sub-
species, especially from an aircraft, and the multi-species
approach of the investigational team, all animals observed
were classed as caribou. There was also no attempt made at
obtaining numbers cf animals involved.
The main objectives of this program were to determine
3Classification follows Banfield 1962, and Hall and Kelson
1959.
42
the present distribution of caribou, to map and describe
their range, and to assess the potential impact on the
caribou and their habitat of the construction of an
underground gas pifeline.
5.2.1.2 Study Area
The Porcupine caribou herd that ranges throughout the
northern Yukon is reported on in detail in the following
section (5.2.2). Excluding the area occupied by this herd, a
total of 25 mapsheets bordering the Mackenzie itself are
included in the study area. No part of the Yukon is
included.
5.2.1.3 Methods
The mapping and data gathering were undertaken in four
overlapping "stages". These were as follows:
1. Aerial Phcto Interpretation and Land Unit Mapping
Using all available information on landform, surficial
geology and vegetation, basic homogenous land or habitat
units were outlined on the 1:250,000 topographic base maps.
Each habitat unit was numbered for references and a
basic data sheet was compiled on each.
2. Aerial Range surveys -Winter
Aerial reconnaissance flights using fixed-wing aircraft
were carried out to obtain the data necessary to determine
caribou winter distribution in the land units. Every effort
was made to obtain unbiased visual information on all
designated habitat units. All information obtained was
recorded on data description sheets.
The winter reconnaissance surveys were begun February
1, 1972 and were completed by April 30, 1972. Due to
fluctuations in manpower and weather conditions, it was not
possible to survey some areas during the winter and most
areas were only surveyed once.
3. Aerial Range surveys -Summer
The winter surveys were followed up by summer
observation flights to areas with insufficient or no data.
Although habitat descriptions were the prime objective of
43
the summer flights, observations on spring-summer dispersal
and distribution were alsc made. The same techniques as used
in the winter surveys were used during the summer.
4. Final Map Preparation
All the data obtained were gathered together and
analysed. The areas in which large numbers of caribou and
tracks occurred were noted as heavy use areas. Since caribou
wander widely and variably, descriptions of the la~d units
in which caribou and caribou tracks were observed were taken
as suitable caribou habitat and the range boundary was
extended to take in similar adjacent habitat. This, in
conjunction with any recorded historical data, formed the
basis for the delineation of caribou range.
5.2.1.4 Results and Discussion
The habitat range maps and accompanying descriptions
are included in Atlas 3.
As previously stated, no attempt was made to
distinguish the three sub-species of caribou that may have
been involved in the study area surveys. Howeve~, some
preliminary observations were obtained that are subject to
verification by fu~ther study:
1. There was no evidence of movement across that
section of the Mackenzie River within the study area.
Kelsall (1968) observed limited numbers crossing f~om the
east to the west bank at Fort Norman in the winter of 1950-
51. The river should not present an insurmountable physical
barrier except during the spring flood. It is frozen in
winter, and caribou could swim it easily in summer.
2. All three sub-species are located on the study
area. The woodland caribou, probably the most widespread,
are year-round residents, although some localized movements
take place. They can be found on both sides of the Mackenzie
River as far north as the treeline on the east side, and to
Arctic Red River on the west.
The western groups are restricted to the Mackenzie
Mountains and adjacent foothills and lowlands. In these
areas the range included in the study area is mostly
marginal with the greatest concentrations found further to
the west. Quite large groups were noted along the headwater
44
streams of the Reele, Redstone, Carcajou and Arctic Red
rivers.
Those animals east of the Mackenzie River are more
widespread. Very few concentration areas were noted. They
apparently radiate out in winter from the many plateaus and
mountainous summer ranges. The Horn Plateau is an example of
such an area. Others are suspected but not documented.
The barren-ground caribou, other than the Porcupine
herd, are only found on the east side of the Mackenzie
River. The major group involved is known as the Eluenose
herd. It seems to be composed of two groups. One group may
winter as far south as The Horn Plateau. In most years,
major winter concentrations are east of the study area
(Kelsall 1968), but some animals have been known to spend at
least part of the winter along the Willowlake, Blackwater
and Great Bear rivers, and areas between. The small mountain
ranges extending along the east side of the Mackenzie River
seem to form a barrier to major movements into the Mackenzie
Valley itself.
Another group of the Bluenose herd apparently summers
to the west of the Horton River. In returning to its winter
range, which is usually to the east of Canot Lake, some
animals often swing out across the Crossley Lakes to the
Travaillant Lake Little Chicago area, then to the east
(Hawley, pers. comm.). Such a movement is unpredictable and
was not documented in 1972.
The final group of caribou may be barren-ground
caribou, woodland caribou, feral reindeer or a mixture of
sub-species. They apparently summer just south of the Eskimo
Lakes and winter around and to the north and east of
Travaillant Lake. ~his group, estimated at between 1,000
2,000 animals (Hawley, pers. comm.), does not usually
concentrate in one area like barren-ground caribou but stays
in small groups of 2 to 20, much like woodland caribou.
3. Some observations on spring movements were made
near Wrigley and Sibbeston Lake.
In February and March, caribou were SFatially
distributed throughout the areas to the east of the
McConnell Range. On April 26, numerous tracks were found
along the eastern base of the McConnell Range. Re-tracing
the tracks, it was found that the herds had worked their way
westward from the areas where they were seen in early
February. Because of poor flying conditions in the McConnell
45
Range, attempts to trace and locate the animals were
abandoned.
A similar situation occurred in the Sibbeston Lake
area. Signs of caribou were totally lacking alcng the
Nahanni Range during February and March but they were seen
farther to the east. On June 14, several sightings cf cows
and calves were recorded in the alpine tundra region of the
Nahanni Range.
4. suspected summer ranges and calving areas have been
noted for some woodland caribou groups. That part of the
Mackenzie Mountains in the study area and adjacent small
mountain ranges, such as the Nahanni and Camsell ranges,
often provide summer habitat for small local populations.
The Horn Plateau, the Martin Hills, the Redknife Hills and
the McConnell Range are also suspected to be utilized in
summer by some lowland groups.
Several features of these mountainous alpine tundra
areas are attractive to caribou. The abundant lichens,
mosses and forbs provide excellent forage. This area is
relatively cooler, more exposed to winds and drier than the
forested wintering areas, providing some relief from the
hordes of insects.
Although not documented, these areas may be preferred
calving areas. They provide the open cover and r~gged
terrain features which aid in escaping predators. The
importance of these types of areas has been established in
other regions and could prove essential with some
populations. The majority of the larger groups have
established calving areas outside the study area.
5. Winter range for all sub-species primarily consists
of open black spruce-lichen forests of mature age. The
topography is usually flat to slightly rolling. Numerous
scattered small lakes are common features. Drainage is not
particularly important although better drained areas favor
the production of lichens.
6. All large areas lacking open black spruce forest
cover are usually avoided. This is especially true of
recently burned areas. Just when burns become useable again
varies and depends on regenerating rates of cover species
and lichens. This may run well over 50 years on many
northern sites. In most mcuntainous and hilly areas, caribou
46
rarely go above the treeline in winter although these areas
seem highly preferred in summer. Large boggy areas are quite
often avoided as well. Frozen lake surfaces are regularly
used for bedding, and the emergent vegetation, especially
~yis~tum species, is heavily utilized around the edges.
Lakes are quite often used for resting areas during sunny
winter days.
7. Almost all of the caribou ranges found on the study
area are located on the margins of major ranges that occur
to the east, west and north of the study area. The small
population north of Travaillant Lake is one exception. There
may be other small local populations whose range is mostly
within the study area as well.
5.2.1.5 Conclusions
All studies have indicated the variability and
unpredictability of caribou movements. Fortunately, the
presently proposed pipeline route does not cross any
regularly used winter range of the large Bluenose herd.
Animals in quite large numbers have been known to occur
in the vicinity of the route, but the Franklin Mcuntains
tend to act as a natural barrier for the majority of this
herd. There is the distinct possibility that in some year,
or years, during and following construction, large numbers
of wintering barren-ground caribou may be encountered.
The small herd of migratory caribou north of
Travaillant Lake can be expected in the vicinity of the
pipeline route each winter during and after construction,
although this could vary annually.
Woodland caribou range will be crossed by the pipeline
route at several locations south of Camsell Bend. After the
pipeline crosses the river going north, however, it will
keep generally to the western margin of known range until
Little Chicago. Here it passes into the region around
Travaillant Lake. Woodland caribou in this vicinity are not
believed to be abundant and should not be directly affected
to any great extent.
Many more data are needed on distribution, abundance,
and movement behavior before accurate predictions can be
made on impact.
47
5.2.1.6 Implicaticns
1. There are no presently known areas of heavy caribou
use that will be directly affected to any great extent by
the presently propcsed routes east of the Mackenzie Eiver.
2. Disturbance from various construction
during and after construction will occur. The
be temporary in most cases and not serious.
traditionally variable and may not be
disturtances are short-term.
sources both
result should
Caribou are
affected if
3. Disruption of movement patterns is a distinct
possibility in a few local areas and populations. !he herd
north of Travaillant Lake could especially be affected. So
little is known on movement patterns that it is imFossible
to predict implications.
4. Increased hunting pressure along the pipeline
corridor itself, and radiating from the increased population
in centers along the route, may have an important influence,
especially on the scattered woodland caribou herds.
5. Harassment from low-flying aircraft, both private
and industrial, will increase and may have a disastrous
effect on local populations. The larger groups will be most
affected by this type of disturbance.
6. An increase in the number of wildfires could be
disastrous to the caribou. Caribou avoid burned areas and it
takes a very long time fer these areas to reach the climax
vegetational stages that will support them.
5.2.2 The Porcupine herd of Barren-ground Caribou
5.2.2.1 Introduction
For millennia the migratory barren-ground caritou was
the primary source of food and clothing over great tracts of
the canadian North. In recent times the importance of the
barren-ground caritou as a nutritional mainstay for northern
peoples has diminished somewhat.
The Loucheux Indians of interior northern Yukon and
Northwest Territcries as well as the coastal Eskimos
developed life styles which relied heavily on the seasonal
appearance and movement of migratory barren-ground caribou.
48
In the northern Yukon, the importance of the barren-
ground caribou to the native peoples has diminished slightly
over the past decade. The native inhabitants no longer
depend extensively on caribou for clothing, but they do
depend overwhelmingly on the caribou as a food source.
The Porcupine herd of barren-ground caribou has been
termed the "International Herd'' since its yearly movements
involve parts of northeastern Alaska as well as the northern
half of the Yukon. Until very recent times the size and
importance of this herd were disputed. Since the 1950's
various Canadian and Alaskan agencies claimed that the
Porcupine herd represented as few at 10,000 or as many as
200,000 animals. Studies carried out over the past two years
suggest that figures from 70,000 to 140,000 animals more
truly represent the population status of the Porcupine herd.
This herd remained essentially untouched outside of
native harvests until the appearance of the whaling industry
in Arctic waters. Frimitive harvest methods available to
Indians and Eskimos were vastly improved with firearms
obtained by Indians at Fort Good Hope as early as 1825, and
later from whaling ships wintering at Herschel Island and
from representatives of the Hudsons Bay Company. The whaling
industry and the Hudsons Bay Company both reached the
northern Yukon in the 19th century.
Through a barter system, native hunters were encouraged
to provide meat for whaling crews wintering at Herschel
Island. The demands of resident natives and wintering
whalers (on occasion exceeding 2,000 men) reduced the
Porcupine Caribou herd by the early 20th century.
Since the cessation of the whaling era in Arctic
waters, the Porcupine herd has apparently recovered,
although there are no reliable figures for historical
numbers. At present, harvest of caribou in the northern
Yukon, with exception of animals taken on the Dempster
Highway, is nearly exclusively by natives.
With intensified attempts at economic exploitation of
non-renewable resources in the canadian Arctic and
Subarctic, public awareness has focused on the real or
potential dangers to the environment and to renewable
resources, represented in this case by barren-ground
caribou. In the northern Yukon the Porcupine Caribou herd
are increasing in value, both economically to the natives
depending upon them as a food source, and aesthetically to
the southern Canadian society.
49
This survey was undertaken to determine the size and
status of the Porcupine caribou herd. Also of major interest
were movements of this herd which might conflict in any way
with any industrial or exploration activities as well as any
construction of transportation facilities such as pipelines
and highways.
5.2.2.2 Methods
The field work described in this report was initiated
on February 7, 1972 by c. Jorgenson and continued by other
members of the Canadian Wildlife Service until April 30,
1972 when E. de Bock assumed responsibility. The survey
continued through to October 31, 1972. Field work included
intensive aerial surveys and aerial photography as well as
surveys from ground camps to count and classify animals in
an attempt to determine the status of the Porcupine Caribou
herd. Survey efforts were restricted to the Yukon Territory
north of Dawson City, to the Beaufort Sea, and east of 142°
longitude. The following methods were used.
A ski-wheel-and float-equipped Cessna-185
used for most survey flights. A STOL equipped
DeHavilland Beaver and a Piper Aztec C
occasionally.
aircraft was
Cessna-185, a
were used
During the 1972 field operations, surveys were based on
Old Crow and Dawson City, Yukon Territory. All but three
weeks of field work were carried on out of Old Crow.
Wintering caribou were located in early February by
systematically flying major drainages of the Peel and
Porcupine rivers. Surveys also included areas where caribou
were known to have wintered, such as the southern Richardson
Mountains. The extent of wintering areas was determined by
flying the perimeters of areas used. Wintering caribou were
periodically checked frcm early February. Tracks, feeding
craters and the presence of animals were accefted as
indicators of wintering areas. Perimeters of wintering areas
were plotted on 1:250,000 and 1:1,000,000 topographical
mapsheets.
Migratory routes were determined by continued air
surveillance and by transect flights. In transect flights,
parallel transects 4 or 8 miles apart were used. Flight
elevations varied from 300 to 600 feet above the ground
surface. Migraticn routes were traced by presence of animals
or tracks and trails which were visible from survey
altitudes.
50
Population estimates were derived by directly
enumerating small groups and estimating numbers of animals
in large group~. When gathering data on population
estimates, the aircraft was slowed to 110 to 120 miles per
hour.
Photography was used extensively in the 1972 field
surveys.
Photography was also used on large massed herds.
Photographs were filed according to date and location, and
later estimated and counted for cross-checking initial on-
site estimate~.
In this report, seasons have been arbitrarily divided
into the following time periods: winter (November 1 to March
15), a period of permanent snow cover; spring (March 16 to
June 15) , a period of disappearing snow and break-up of
lakes and rivers; summer (June 16 to August 31), a period
when mean minimum temperatures are above freezing; and fall
(September 1 to October 31), when snow cover is not yet
permanent.
5.2.2.3 Results and Discussion
Winter Range of the Porcupine caribou Herd
both
Yukon
Indeed,
caribou
caribou
Historical documentation and native folkloie
indicate that all areas north of Dawson City,
Territory, may be considered caribou winter range.
all areas of the northern Yukon have been used as
winter range in past years. Large numbers of
historically wintered on the coastal plains and
recent times done so in Alaska. Loucheux Indians of
describe caribou wintering on the nearby treeless
Flats.
have in
Old crow
Cld Crow
The most typical caribou winter ranges are located
south of the treeline or south of the Porcupine River.
Winter range of the barren-ground caribou in the western
Arctic differs from that of caribou in the central or
eastern Arctic. Western Arctic winter ranges are frequently
in mountainous areas. caribou utilize both the mature spruce
lichen forests of the foothills and valleys, and the high
open slopes in mountainous areas. In the winter of 1971/72
the Porcupine herd utilized typical winter ranges.
Caribou wintering areas are characterized by mature or
stable vegetational conditions, generally in mature spruce -
51
lichen forests. Wintering areas which have been used by the
Porcupine caribou herd vary from tundra plains on the Arctic
coast, through laxe margins and wet tundra areas of the Old
Crow Flats, to the extremely mountainous areas south of the
Peel River.
General Migration Routes
The migratory barren-ground caribou of
herd traditionally move north and northwest
every spring. Basic routes are used in
migration and variations of these routes are
their fall southward migration.
the Porcupine
into Alaska
their spring
followed in
Spring migration takes place over three separate routes
which have been termed the Richardson Route, Old Crow Route,
and the Western Route (Renewable Resources Consulting
Services Ltd., 1971). Caribou travelling all three routes
ultimately mingle and travel the same route in the terminal
stages of their spring migration.
A. Richardson Route
The Richardson Route lies along the Richardson
Mountains. Northward migrating caribou generally reach the
southern Richardscn Mountains by crossing the Peel River
from two areas, the Knorr and Trevor ranges and from the
Chappie Lake -Hungry Lake area. Caribou moving north along
the Richardson Mountains generally enter them across their
southern end and move north along the nearly snow-free
crests. The main movements are along the eastern crests to
about the level of the Vittrekwa River. From this point
caribou move to the western crests of the Richardson
Mountains at approximately the level of the Rat River. The
caribou fan out and approach the south side of McDougall
Pass from Horn Lake on the east to the Waters River on the
west.
The Richardson Route terminates in the eastern Barn
Range where it unites with the Old Crow and Western routes.
The caribou sweep around from Mount Goodenough across the
headwaters of the Big Fish River and Rapid Creek to the Blow
River.
B.
move
from
The
Old Crow Route
Caribou migrating north by the Old Crow route generally
out of the Ogilvie Mountains and cross the Peel River
about the level of Hungry Lake to the Whitestone River.
route lies along low wooded ridges across the southern
52
and southwestern portions of the Eagle Plains west to the
Miner River. Caritou travelling the Old crow Route swing to
the northwestw moving up to the Whitestone River and along
the ridges between the Whitestone and Miner rivers to the
area of the Fishing Branch River and the southern Keele
Range. From the Fishing Branch River the route moves north
to an area immediately south of Lone Mountain in the Keele
Range. on reaching the northern Keele Range the caribou
disperse and cross the Porcupine River from the Alaskan
border to near the waters River. Large numbers of caribou
cross the Porcupine River in the vicinity of Old Crow at
traditional river crossingsw to be described later.
After crossing the Porcupine River, caribou disperse
across the Old Crow Flats and wander to the southern edge of
the Barn and British mountains.
The Old Crow and Richardson Migration Routes Jo~n in
the Barn and British mountains then continue on to the west
and northwest to eastern Alaska.
c. Western Migration Route
The Western Migration Route is the shortest of the
three migration routes which can be defined. This route
begins in the Tatonduk River watershed. Some caribou using
this route swing up the western side of the Ogilvie
Mountains, moving north along the Alaskan border directly
towards the Salmon Fork River. However, the major migration
route lies up along the Miner River. The Western Migration
Route goes through the Bear cave Mountain area where it
joins the Old Crow Route and continues northward as the Old
crow route. Both portions of the Western Migration Route
have joined the Old crow Route by the time the level of Lone
Mountain is reached.
There are an estimated 75,000 to 80,000 caribou
migrating north each spring over the routes described. An
estimated 35,000 tc 40,000 caribou migrate north over the
Richardson Route. The Western Migration Route is used by an
estimated 15,000 caribou. The balance of migratory caribou
moving north take the Old Crow Route.
Important Areas
In two field seasons it has been possible to define
four particular habitat situations which seem to hold
special significance for migratory caribou. The first and
most general of these situations can be termed staging
areas. The significance of staging areas in the yearly cycle
53
of the caribou is extremely difficult to assess. They seem
to be repeatedly used at approximately the same time each
year, often for approximately the same length of time.
Superficially, staging areas appear to facilitate grouping
prior to definitive movements. Some staging areas may be
used for more than one purpose at different stages of the
caribous• yearly cycle. For example, the valley lying
between the Malcolm and Firth rivers appears to hold dual
significance for caribou. The valley is initially occupied
by herds of calving caribou and hence may be termed a
calving area and as such is extremely important to the
welfare of the caribou. This same valley is also used as a
staging area for large post-calving herds in early July,
immediately after returning from Alaska.
Other staging areas which have been recognized are: the
Knorr and Trevor range areas south of the Peel River. These
staging areas are used extensively in early spring,
immediately prior to migration north to the Richardson
Mountains.
The Keele Range immediately south of Lone Mountain is
also fleetingly used as a staging area. caribou migrating
north pause briefly when reaching the area south of Lone
Mountain. Then the caribou disperse east and west from Lone
Mountain and move north toward the Porcupine River.
The area between the headwaters of the Blow, Driftwood,
and Bell rivers as well as the headwaters of Rapid Creek is
recognizable as another staging area. Large post-calving
herds move into these highlands and mill around, generally
remaining on the high treeless uplands. This area is used
for approximately 10 to 14 days during mid-July.
The following characteristics seem typical of caribou
staging areas: they are open and treeless, but fairly well
vegetated with willows, sedges, some grasses, lichens and
cotton grass.
Spring staging areas are high, rolling, wind blown
ridges with little snow cover. They are used prior to
initiation of migration and occasionally during migration.
Summer staging areas are open rolling valleys and
uplands such as described above and are situated between the
Firth and Malcolm rivers and at the headwaters of the Bell
River. These areas are generally completely snow free with
exception of infrequent snow banks.
There are three ether situations, mineral licks,
54
calving areas and river crossings, which have recognizable
importance for ca~ibou. Mineral licks are important because
they attract caribou. One very heavily used mine~al lick,
discovered in 1972, is on the east bank of the Firth River.
This mineral lick is used extensively by female and young
caribou and may in fact contribute to the value of the
staging and calving area in which it is situated.
Calving areas are obviously important areas to the
welfare of a caribou herd. Five discrete calving areas were
located in the northern Yukon during the 1972 field season.
All calving areas found were on existing migration routes to
Alaska.
The calving areas located have several conditions in
common, the first and foremost being an absence of snow.
Calving areas are all gently rolling valleys, well drained
and fairly sheltered. In all calving areas there are good
growths of cotton grass, the main food species of caribou
during early summe~.
Other important areas used by caribou are the river
crossing sites. Many river crossings appear to be
traditional, as natives of the area have taken caribou at
these points for uncounted generations. Preferred river
crossing points have several recognizable attributes.
caribou prefer to cross rivers from points where there is a
gentle slope with good footing. They prefer to cross to
similar slopes or broad shingles on the opposite shore.
Caribou seem to be drawn into each crossing point from a
considerable distance, as caribou were observed following
river banks for several miles before crossing. Crossing
points are generally in the apex of bends in the river. The
point furthest in the direction of travel in the loop or
bend of the river apparently creates the most favorable
crossing condition. However, some rivers, such as the Firth,
present serious obstacles in the form of extensive reaches
of deep canyons where caribou are forced to cross under
extremely perilous conditions.
Chronology of caribou Movements
Since the migratory barren-ground caribou of the
Porcupine herd are deemed of primary importance amongst the
wildlife resources of the northern Yukon, special emphasis
was placed on surveys of their movements. Aerial su~veys of
the Porcupine Caribou herd were maintained throughout the
1972 field season, and a summary of these observations for
spring, summer and fall fellows.
55
A. Chronology of Spring Movements
Aerial surveys of the Porcupine Caribou herd were
initiated in early February, 1972. Initial contact with
caribou was made on February 8, while animals were still
dispersed on their winter ranges. Most caribou were
wintering south of the Peel River. In early February a group
of caribou were located north of the Peel River, between the
Whitestone and Miner rivers. A large area was also being
utilized between Parkin (Chevron Standard Oil Exploration
base cam~ and the Peel River. Significant numbers of
caribou were located along the Dempster Highway on February
8.
A herd of approximately 4,000 caribou which had elected
to winter in the eastern Richardson Mountains near the
Vittrekwa River was still stationary between the Trail and
Road rivers on February 12. This group of caribou had moved
from the sparsely forested lower slopes to the crests of the
Richardson Mountains onto the Richardson Migration Route by
February 21. The caribou in the Richardson Mountains had not
seriously begun to move by February 21, 1972.
Caribou were beginning to move north by mid-March. In
survey flights along the Dempster Highway and the major
tributaries of the Peel River, few caribou were observed. An
estimated 10,000 caribou were located on the crest of the
Trevor Range staging area on March 21. caribou were
beginning to group on the Knorr Range staging area at the
same time. caribou were moving northward out of the Ogilvie
Mountains by March 21. Caribou in the Tatonduk River
watershed had not begun to move by March 26, 1972.
survey flights carried out on March 28 revealed that
large numbers of caribou were moving north by the Richardson
Migration Route. Four separate herds of 2,000; 7,000
10,000; 7,000 -10,000; and 15,000 -20,000 caribou were
located as far north as the Road River.
Good numbers of caribou were preparing to cross
McDougall Pass by March 28. Large numbers of caribou had
crossed McDougall Fass and entered the northern Richardson
Mountains by April 21. Migrating caribou were sweeping to
the northwest across the headwaters of Rapids Creek toward
the Blow River by April 28.
In early May, caribou moving north by the Richardson
Migration Route were travelling rapidly. Several hundred
caribou had moved west of the Blow River by May 1. As
previously explained, once caribou had reached the Barn
56
Mountains all migration routes merged into one migration
path which spanned the entire mountain range.
By late April many caribou were beginning to drift
north by the Old Crow and Western Migration routes. Survey
flights on AFril 27 revealed large numbers of caribou
immediately south of Chappie Lake. At this time, caribou
north of the Peel River and west of the Richardson Mountains
were remaining essentially stationary.
survey flights into the Ogilvie and Wernecke mountains
on May 3 revealed extensive northward movements of caribou.
In addition to location of caribou moving north on the Old
crow Migration Rcute, 2,500 caribou were observed on the
Trevor Range staging area.
In the period May 1 to May 5 caribou began migrating
rapidly to the north using both the Old Crow and Western
Migration routes. Caribou from the Tatonduk River watershed
were moving down the Miner River and caribou from the
Ogilvie Mountains and Peel River were advancing onto the
Fishing Branch River by May 5. Many caribou from the Hungry
Lake area moved northwest across the Whitestone River
towards the Fishing Branch River on this date also. In a
survey flight south of the Peel River another 800 caribou
were located en the Trevor Range. From these observations it
appeared that caribou move onto the Trevor and Knorr ranges
for a short time to group up then immediately start north
across the Peel River. By May 7 large numbers of caribou
from the Tatonduk River drainage were moving north ever Bear
cave Mountain. On May 8, caribou were seen moving north into
the Keele Range directly south of Old Crow. Within three
days (May 11) caribou were approaching Lone Mountain. During
a flight on May 11, 75 caribou were observed in the
headwaters of the Bluefish River with additional animals
seen near Johnson Creek moving into the northern Keele
Range.
On May 13, 1,450 caribou were approaching the Pcrcupine
River across the flats immediately south of Old Crow. At
this time, large numbers of caribou were moving north out of
the Keele Range at the headwaters of Johnson Creek. By May
14 some caribou had reached the Porcupine River and large
numbers of animals were rapidly approaching the river on a
wide front. The Porcupine Caribou herd began crossing the
Porcupine River immediately west of Old Crow and at the
mouth of Lord Creek by May 15. By May 17 caribou were
crossing the Porcupine River in large numbers. In addition
to these two initial crossing points, caribou began crossing
the Porcupine River at many points by May 19, and were
57
moving into the Barn and Eritish mountains by May 20.
caribou migrating north by the Richardson Route were
joined by caribou from the Western and Old Crow routes in
the Barn and British mountains by approximately May 20. By
this date, most caribou from the Richardson Mountains had
passed through the British Mountains.
Once across the Porcupine River the migratory impetus
appeared to decrease; by May 26 caribou were leisurely
drifting northward in small groups.
Many caribou in the Barn and British mountains and on
the North SloFe began to group into calving or nursery
bands. The first caribou calf was observed on June 3; by
June 8, 300 new calves were counted.
Five separate calving areas were identified in early
June. A mineral lick located near one calving area on the
Firth River appeared to attract large numbers of pre-and
post-parturient cow caribou to the area. Following calving,
caribou continued to move to the west into Alaska.
Fragmented groups of caribou (mostly males) kept moving west
into Alaska until the return of the post-calving herds in
early July.
B. Chronology of summer Movements
During survey flights in the Davidson Mountains on July
10, 1972, large returning post-calving caribou herds were
located. An estimated 50,000 caribou were observed as they
moved up the Clarence River to the Yukon -Alaska border.
Two large herds re-entered the Yukon and moved east to the
staging area between the Firth and Malcolm rivers, reaching
this point by July 12. All caribou which had returned to the
Yukon by July 12 regrouped in this staging area.
The large post-calving herds remained in the staging
area for a short time. By July 15 these herds had begun to
fragment as they moved to the east across the Firth River.
Caribou moving tc the southeast moved along the northern
edge of the British Mountains. At this point, it shculd be
stressed that post-calving herds are generally larger and
much more compact and thus much more vulnerable than at any
other time of the year. By July 15 a single herd, estimated
to contain 20,000 caribou, was situated between the Spring
and Trail rivers in the northern foothills of the British
58
Mountains. Small fragmented herds of caribou were crossing
the Babbage River on July 16. An estimated 40,000 caribou in
fragmented herds were alsc located between the headwaters of
the Trail and Babbage rivers. When moving east, caribou used
nearly every pass tetween the Clarence and Trail rivers.
During survey flights carried out in mid-July it was
determined that small fragmented herds of caribou ccntinued
to enter the Yukon for some time after entry of the two
major herds. No estimates of numbers for the above small
herds entering the Yukon are available, because it was
impossible to intercept them before they had entered areas
where caribou were already present.
On July 18 large caribou herds were seen across the
Babbage River. One herd which had crossed the Babbage River,
estimated at 12,000 caribcu, had moved as far east as the
headwaters of Dog Creek. Post-calving herds continued to
move to the southeast, and by July 21 a herd of 20,000
caribou had crossed the headwaters of the Blow River and was
entering the northern Richardson Mountains. Two additional
large herds totalling an estimated 30,000 caribou were
approaching and crossing the headwaters of the Blow River by
July 21. All caribou had reached the staging area between
the headwaters of the Blow, Bell, Driftwood and Fish rivers
by July 24, 1972. The above staging area shall be referred
to as the Bonnet Lake staging area. Post-calving caribou
herds remained in the Bonnet Lake staging area from July 24
through to July 31, 1972, when they began to return to the
west across the Old Crow Flats.
Most caribou returned to Alaska by moving west across
the Old Crow Flats. Significant numbers of caribou moved to
the northwest into the Barn and British mountains, then
continued westward to Alaska. By August 2, 5,000 caribou had
reached Black Fox Creek, with 12,500 more approaching this
stream. By August 5 many caribou had reached Alaska.
Survey flights subseguent to the return of the caribou
to Alaska revealed that not all the post-calving caribou had
returned to Alaska. Flights over the northern Richardson
Mountains indicated that possibly as many as 2,500 to 4,000
caribou had remained in this area.
c. Chronology of Fall caribou Movements
In the interval between the exit of caribou from the
Yukon in early August and their fall re-entry in Seftember,
1972, periodic survey flights were made into eastern Alaska
in search of returning caribou. A survey flight on Seftember
59
2 encountered caribou which appeared to be drifting to the
east out of Alaska. A later flight, on September 6, revealed
2,500 caribou crossing the Coleen River in Alaska. Returning
caribou drifted eastward in a leisurely manner until
September 12, when 4,000 caribou were located in Thomas
Creek. An estimated 15,000 caribou were observed moving to
the east from the Coleen River in Alaska. Inclement weather
in the period from September 12 to 15 curtailed survey
flights, but on September 16 large numbers of caribou were
seen moving eastward across the south slopes of the Earn and
British mountains. Follow-up flights on September 17
revealed 33,000 caribou mcving southeast across the Old Crow
Flats. caribou began crossing the Bell River by September 19
and the Porcupine River by September 21. By September 22
large numbers of caribou were crossing the Porcupine River
and moving into the Keele Range. Initial crossings of the
Porcupine River were made in the area from the Driftwood
River to Berry Creek. During a September 25 survey flight
large numbers of caribou were seen moving south over the Old
Crow Range, and down to the Porcupine River. These caribou
were crossing the Porcupine River immediately west of Old
Crow.
After entering the Keele Range, caribou tended to move
to the southwest. On a survey flight carried out on October
1, we observed an estimated 15,000 caribou in one herd
moving west from the Salmon Fork River to the Yukon -Alaska
border. Increasing numbers of caribou were also located
moving south to the Salmon Fork River at this time. During
the same period caribou were traced south of Bear cave
Mountain and large numbers of caribou had moved from the
eastern Keele Range to the area of Bear cave Mountain.
During survey flights into the Richardson Mountains on
October 2, an estimated 1,500 caribou were located moving to
the northeast frcm the Old Crow Flats, while increasing
numbers of caribou were seen moving north from the Pcrcupine
River.
On survey flights made to the south and southwest of
the village of Old Crow on October 4 and 7, several thousand
caribou were seen ~oving west into Alaska in an area between
the Salmon Fork and Black rivers to the south, and the
Porcupine River to the north. There was also a trend to move
to the northwest towards the Porcupine River. During
extended flights UF the Coleen River in Alaska, the vanguard
of a very large movement to the northwest was encountered;
the caribou were beginning to cross the Coleen River to the
northwest. Subsequent caribou survey flights beyond the
Coleen River into the interior of Alaska became logistically
60
difficult and were abandoned. Indirect reports from pilots
flying in the inteiior of Alaska indicated that caritou had
approached Arctic Village, a native settlement approJimately
190 miles west cf Old Crow on the Chandalar River, in
numbers exceeding 30,000.
Aerial surveys were then concentrated on remnants of
the Porcupine Caiibou herd which were still moving south
towards the Ogilvie River. On October 8 we saw caribou
approaching the Dempster Highway near Mile 140, and several
animals had already crossed the highway near Mile 110. At
this time there was a definite movement to the southwest in
the southern caribou migration. Inclement weather hindered
survey flights fiom October 9 to 13, when a large caribou
movement was detected at the headwaters of the Ogilvie
River. caribou which had moved south were now travelling
west towards the headwateis of the Tatonduk River and the
Mount King -Mount De Ville area.
Observations carried out between October 17 and 29
showed that after crossing the Ogilvie River, the migratory
impetus decreased. The caribou drifted southwest toward the
Yukon River and the mountainous region north of it. On
October 29 large numbers of caribou were seen on ridges
along the Yukon -Alaskan border above the Tatonduk Eiver.
During frequent survey flights in the period of October
17 to 29 along the Dempster Highway, it became clear that
few caribou approached this area in 1972. Those caribou
which did cross the Dempster Highway were moving to the
southeast. The bulk of the animals crossed the highway near
North Fork Pass then moved east toward the headwaters of the
Hart River.
Caribou which approached the headwaters of the Hart
River largely retraced their paths and moved west into the
mountains around the headwaters of the Blackstone River.
Survey flights in the Ogilvie Mountains and the Dempster
Highway areas were terminated on October 29, 1972.
In late October, two survey flights were made into
eastern Alaska. On October 21 a flight was made through the
Salmon Fork River drainage and up the Coleen River to the
Firth River thence back to Old Crow. An estimated 2,000
caribou were found moving south from the Salmon Fork River
area.
During this flight, many fresh caribou trails were seen
crossing the Coleen River and leading east. Fresh trails and
caribou observed on the Old Crow Flats suggested that as
61
many as 2,500 -3,000 animals may have returned from Alaska
by October 21. The final survey flight of 1972 was carried
out on October 30. Fresh caribou trails crossing into the
Yukon and around Bilwaddy and Ammerman creeks as well as
trails and feeding craters across the north edge of the Old
Crow Flats and Timber Hill indicated that more caribou had
returned to the Yukon from Alaska during the period from
October 21 -30. No estimate was possible on the numbers of
returning caribou.
At the time the survey flights were ended, the majority
of the Porcupine caribou herd was in Alaska, with an
estimated 15,000 animals in the Tatonduk River drainage. In
addition to the above, approximately 2,000 caribou were in
the Richardson Mountains and possibly as many as 5,000
caribou were dispe~sed frcm the British Mountains across the
Old Crow Flats into the Old Crow Range.
The Variations of caribou Movements
Data gathered on the Porcupine Caribou herd by various
agencies over the past seasons provide some suggestion of
the possible variations, both chronological and spatial, in
the yearly cycle of migratory barren-ground caribou.
To deal witb the potential variations of caribou in
regards to movement patterns or usage of particular areas,
it is necessary to distinguish between long and shcrt term
departures from "traditional" movements. Terms such as
11 traditional" migration routes, winter ranges, calving areas
or river crossings are recurring throughout caribou
literature. "Traditional" is accepted here as meaning an
inherited unchanging pattern. Variations of traditional
movement and behavior patterns must be separated from their
short-term counterparts, in order to arrive at a correct
concept of caribou movements.
Short-term variations
As a result of two years observations, some remarks on
yearly variations and their possible causes can be made. For
the purpose of this discussion it has to be assumed that a
short-term variaticn does not last more than five years. The
field data available suggest that variations in time as well
as in directions of movements are likely to occur from year
to year. Such fluctuations in timing are probably closely
correlated with weather and snow conditions, as are
variations in movement patterns.
From field data available, the following conclusions
are drawn. Chronology of spring movements during 1571 and
1972 for the various migration paths show variations of a
week for the Old crow Route and up to six weeks for the
Richardson Migration Route. Summer movements began 10 days
later in 1972 than in 1971 and ended a week later in 1972.
Fall movements began approximately two weeks later in 1972
than 1971, although caribou reached the Ogilvie River on
nearly the same date both years.
Basic spring migration patterns were nearly identical
for both years, although there was a shift of winter ranges.
Summer movement patterns during these two years were nearly
exactly the same; although the number of animals involved
was not.
Fall movements were entirely different for each of the
two years for which data are available. Normally, caribou
from the northern Yukon and northeast Alaska move southward
to the area south of the Peel and Ogilvie rivers by way of
the Richardson and Old Crow migration routes, which they did
in 1971. In 1972 sreall segments of the Porcupine caribou
herd moved south of the Ogilvie River or into the Richardson
Mountains. The bulk of the caribou herd moved northwest into
Alaska to the Chandalar River near Arctic Village.
Long-term Variations
Historical documentation indicated that over long
periods of time caribou movement patterns are relatively
stable. Life-time residents of Old Crow report that there
have been periods of up to several years when the caribou
shifted their migration routes to such an extent that they
completely bypassed Old Crow.
several pieces of indirect evidence point to the long-
term or traditional stability of caribou migration routes
and movement patterns. Crossing points exist en the
Porcupine River where the Loucheux Indians have ambushed
caribou for untold generations. Hunting camps and
settlements such as Old Crow have come into existence
because of the dependability of such caribou movements
through the area. ~he presence of eight caribou fences, most
of which must be several hundred years old, all on
migrational routes, testify to the long-term stability of
caribou movements.
Within short time spans, up to several years, 1ovement
chronology can vary by months. Migration routes may or may
not be used and movements may in fact not occur.
62
63
over long periods of time, measured in human
generations, it would ap~ear that caribou movements are
relatively dependable and in fact the term "traditional" rs
acceptable.
5.2.2.4 Speculations on Impact of the Pipeline
There are two specific periods during and after
construction in which any pipeline could be expected to have
an effect upon a herd of migratory barren-ground caribou.
Pipeline impact on a caribou herd during the construction
phase can take several forms.
Taking the variability of migration chronology and
movement patterns into account, there are several
possibilities for catastrophic pipeline effects on caribou.
caribou during their spring migration encountering several
miles of open ditch, large construction cam~s, and
continuous vehicular and air traffic may exhibit one or more
of several reactions. Migrating caribou may simply retreat
and move around ccnstruction activity ignoring the constant
vehicular and air traffic. A caribou herd might also move
through the construction zone, ignoring its activity, and
continue on their way. Another equally plausible reaction is
that caribou would simply refuse to move by or around
construction. In effect, migration would halt, and caribou
might return to the south. The effect of caribou going back
to the south could be the loss of much of, or an entire
cohort, as calves would be dropped under conditions
precluding survival. This might also be true if a migration
or subsequent migrations would be deflected from their
traditional route. A fourth possibility is that caribou
would blunder into construction activity, fail to cross open
ditches and perish. The atove speculations all assume that
construction activity is taking place concurrently with
widespread caribou migrations. Many deaths would occur if
ditches were to be enccunterd by the massed, close packed
post-calving herds which may consist of 50,000 -60,000
caribou in near body contact.
Air traffic in large volume may have an unsuspected
impact on migrating or calving herds of caribou. Harassment
by air traffic may disrupt caribou movements and behavior to
such a degree as to cause abortion, exhaustion and death of
parturient cows or abandonment of young.
The presence of large numbers of workers, many of whom
will be hunters who may well try to take caribou against
regulations, may also have seriously detrimental effects on
the welfare of a migrating caribou herd.
Post-construction pipeline effects on migratory
are potentially as disastrous to caribou and their
as possible construction impacts. There are
potential effects on caribou or their habitat
existing underground pipeline could have.
64
caribou
habitat
several
that an
The effect of the presence of compressor and
refrigerator stations and their concurrent disrupting noise
on caribou is open to speculation. It is possible that such
stations would attract, frighten or have no appreciable
effect on caribou. Stations which would frighten caribou,
could have a detrimental effect in key areas such as in the
midst of calving areas, preferred staging areas, preferred
migration routes or traditional river crossings.
Pipeline rights-of-way and berms of underground
pipelines both have potential for deleterious impact on
migratory caribou and their habitat. The fcllowing
possibilities should be considered. An open pipeline right-
of-way might attract caribou. They might prefer to travel on
it, which might deflect migration movements with possible
disaster to the herd. A right-of-way and a berm might act as
a barrier which caribou refuse to cross. Assuming that
caribou would cross a pipeline right-of-way and the probable
berm, it remains to be seen how they would react to the
presence of heavy growths of artificially seeded pctential
food species. Such potential food species might attract
caribou causing migration deflection.
The presence of a pipeline right-of-way and/or
artificially seeded vegetation might induce caribou to
travel along the pipeline right-of-way. There are an
estimated 70,000 tc 140,000 caribou in the Porcupine Caribou
herd; 70,000 animals travelling down a pipeline in an area
where the insulaticn layer has already been damaged or
destroyed may be disastrous. Thermokarst formations could
result from habitual use of a pipeline right-of-way by large
numbers of caribou.
A possibility which also has to be considered is that a
pipeline right-of-way and access to such a right-of-way may
result in increased harvest of caribou through increased
accessibility.
The above are all speculative in nature at this time
since there are insufficient data on caribou biclogy or
behaviour to state with any certainty what pipeline impacts
will be.
65
5.2.2.5 Recommendations
Preventative recommendations are difficult to crganize
where data are insufficient. There are insufficient data on
construction and post-construction aspects of Froposed
underground or above-ground pipelines. There are few data on
caribou reactions to the speculative situations of the
previous section.
The following recommendations will be based upon
assumptions as to the conduct of pipeline construction. In
all cases it will be assumed that caribou reaction will be
negative.
It is assumed:
a. That construction will take place during winter except
in mountainous areas where there may be summer const~uction.
b. That there will be three large construction camps each
of 500 -700 men.
c. That each camp will have approximately six miles of open
pipeline trench at any one time.
d. That all trenches will be filled in during the summer.
e. That extensive use will be made of helicopters and
fixed-wing aircraft.
f. That concerned authcritive environmental agencies will
be able to exert scme measure of control over construction
and chronology of construction.
With the above assumptions in mind it is reccmmended
that:
a. All construction activity be halted prior to spring
caribou migrations. This would entail maintaining an aerial
surveillance of the caribcu f~om early February. Otherwise a
tentative period for closing down construction activity
would be from March 1 to November 15.
b. All construction camps, equipment, and any open trench
be completely enclosed by snow fencing and abundant flagging
so as to create a visual as well as a physical barrier at
these points.
66
c. All pipeline trenches be closed by no later than March
1 •
d. Minimum altitudes {2,000 feet above ground)
corridors be designated for all air traffic.
and air
e. Absolutely no firearms or private all-terrain vehicles
be allowed amcngst construction crews.
f. Extensive impact and manipulative studies be carried out
immediately, on caribou as well as other important species
which may be affected by construction and existence of a
pipeline. Such studies would allow the Canadian Wildlife
Service to more effectively review consortia recommendations
for the protection of caribou and other affected species.
Table 3. A summary of the expected effects upon caribou by the activities
associated with the construction of a gas pipeline.
Activity
Fire resulting from
pipeline or highway
construction
Pipeline berm
Pipeline construction
Aircraft use on
pipeline project
Harassment from any
source
Buried pipeline or berm
Potential Effects
Destruction of climax forest
wintering habitat for caribou
Large numbers of caribou
travelling on a berm might
cause erosion of the berm with
resultant exposure of pipe
and interference with revegetation
There is a need to time
construction to avoid the caribou
calving period and to avoid any
construction procedures that
would alter the environment
critically at calving time
Although caribou can be disturbed
by aircraft at any time during
the year, disturbance would be
particularly serious at calving
time or in winter when the
animals might be pressed by
food shortages
In mid-winter the daily energy
expenditure of the harassed
animals may exceed the energy
present in the total forage
available, thus placing the
animal in a negative energy
balance. If this is compensated
for in increased food consumption
by the animals there would be
an overall increase in pressures
of animals on their food resources
with a reduction in carrying
capacity of the habitat
Pipeline right-of-way would
obstruct caribou migration
resulting in alterations in
patterns of range use and
possible loss of caribou as
a food source to the native
people
Magnitude
Moderate
Moderate
Moderate
Large
Large
Moderate
67
Table 3. Cont 1 d.
Activity
Entire pipeline project
Buried pipeline in
marshy areas of fine
so i 1
Ditching phase of
construction
Pipeline pumping
Total pipeline
development
Oil spills
Potential Effects
Interference with traditional
migration routes, disturbance
of animals on the calving
grounds, creation of increased
fire hazards, and opening of
the country to hunters, would
all adversely affect the
caribou
The refilled ditch may remain
unvegetated and in a fluid
state for long periods of time,
acting as a moat to block or
entrap migratory animals
A large open ditch confronted
by migratory animals would
act as potential trap or
diversion
The noise level of the pumping
stations may be intolerable to
caribou
The increased human population
would result in an increase
in harvest of caribou
Oil spills would not be expected
to have any important influence
on caribou unless ingested
68
Magnitude
Large
Sma 11-moderate
Moderate
Moderate
Moderate
Sma 11
69
5. 3 DALL SHEEP
5.3.1 Introduction
Previous to this study, information on Dall sheep
distribution within the study area was generally quite
patchy. Dr. N. Simmons of the Canadian Wildlife Service had
detailed information for the Carcajou Canyon and Norman
Wells map areas, and scme information on the Sans Sault
Rapids and Fort McFherson map areas. Little or nothing was
known about the remainder of the study area. Any existing
information was used in outlining and establishing
objectives and techniques for this study.
The first phase of the study was to map and classify
Dall sheep range. Information on relative abundance of
animals, and habitat p~eferences, as well as location and
extent of winter ranges, was collected and used in
delineating and classifying habitat units.
The study area was chosen to cover the region likely to
be influenced by construction and operation of a gas
pipeline. Aircraft harassment, disturbance by heavy
equipment, and "tlasting", as well as additional hunting
pressure, are some of the Froblems which may be expected
during the construction period. Noise from compressor
stations and increased recreational and native hunting as a
result of improved access are possible problems in the
operation and maintenance stage.
The presently proposed pipeline route is, for the most
part, well away from the mountains and thus avoids sheep
range. However, in the Richardson Mountains, both proposed
route alternatives pass very near known sheep ranges, and
the coastal route Fasses directly below a major wintering
area.
5.3.2 Methods
Preliminary Office Activity
Initial work on the project began in December, 1971,
with a review of pertinent literature, and determination of
possible sheep areas from aerial photographs. Further
assistance was provided by Dr. N. Simmons, who has been
studying Dall sheep in the Mackenzie Mountains for several
years. His suggestions on distribution, habitat preference,
survey tehcniques, and logistics were most beneficial to the
70
study.
Field Activity
Aerial surveys were based on Fort Simpson, Norman
Wells, Inuvik and Cld Crow. Winter surveys were conducted
from February 7, 1972 to March 30, 1972. Since all of the
surveys were in precipitous mountain terrain, a Bell-206
helicopter was used most of the time. survey personnel
consisted of two observers (one on each side) equipped with
1:250,000 scale maFs, tape recorder and cameras.
Individual sightings, tracks and areas of feeding
activity were plotted on 1:250,000 scale maps, while
descriptions and comments were tape recorded. Numerous
photographs were taken of Dall sheep habitat.
All potential sheep range was investigated. Information
on habitat preferences, winter range characteristics,
distribution and relative abundance of sheep was collected.
Dall sheep were classified as to age and sex; and attempts
were made to correlate population figures with habitat
types.
summer aerial surveys were conducted in July to check
marginal sheep areas, to note seasonal movements, and to
determine populaticn size and extent of summer ranges.
Habitat Classification
Dall sheep are strictly confined to the mountain
portions of the study area, which can be separated into
three main regions: the Mackenzie Mountains, the Richardson
Mountains, and the British Mountains. Evaluation of an area
was determined on a relative basis, considering the study
area as a whole. Because sheep have specific habitat
requirements, a great deal of difficulty was encountered in
attempting to evaluate units on the basis of landform alone.
Information on habitat requirements, habitat preference,
distribution and relative abundance, was collected and
correlated with physical units. As extrapolation of
information from one area to another was impossible, all
potential sheep areas were investigated individually.
Winter is the hardest time on sheep at northern
latitudes, with survival most difficult: therefore areas of
good wintering habitat were given the highest rating -Class
1. Heavily-used mineral licks and concentrated lambing areas
were also given Class 1 ratings.
71
Summer use areas are often on higher slopes where sheep
disperse over large areas of different habitat types. Units
supporting moderate populations of Dall sheep year-round or
large populations during the summer months were given a
Class 2 rating.
Marginal areas supporting a few animals during the
summer period were considered poor habitat (Class 3).
Class 1
A class 1 unit has no obvious limiting factors. Within
the unit are good to excellent wintering areas critical to
the survival of concentrated populations of sheep. Sheep may
be found in Class 1 units throughout the year. Class 1
winter habitat has abundant amounts of food, limited snow
cover, and scattered regions of escape terrain. In some
cases, Class 1 also represents a concentrated lambing area
or heavily used mineral lick.
Class 2
A class 2 area has minor factors limiting Dall sheep.
These units often receive limited use as winter range; but
are mainly used during the summer. Higher elevations, and
more precipitous slopes with sparse vegetative cover are
characteristic of Class 2 units. These summer ranges support
moderate to high numbers of sheep, but animals tend to be
more free-ranging and dispersed than on winter ranges.
Class 3
Class 3 units have moderate to severe limitations for
Dall sheep and lack essential habitat components. These
areas are marginal and receive only limited use during the
summer.
Class q
Class q areas have severe limitations for Dall sheep.
Sheep use in these areas is urcommon.
5.3.3 Results and Discussion
A. Habitat
Dall sheep range within the outlined study area is all
west of the Mackenzie River. Although the Franklin-McConnell
Range appears to have suitable habitat, sheep have never
72
been reported in this area. The study area includes cnly the
periphery of sheep range in the Mackenzie Mountains, some of
which is only marginal habitat.
Dall sheep range does not decrease in quality at higher
latitudes. In fact, low precipitation and extreme cold helps
to limit snow depth and crusting, permitting unrestricted
movement in many areas during the winter months.
One of the main objectives was to locate and assess
winter ranges of Dall sheep. Because northern winters are so
severe, good wintering areas are critical. These wintering
areas are only a small portion of the home range -usually
ridges, slopes, cr plateaus where animals tend to
concentrate. Because of this, these areas are considered
most valuable, and were given the highest ratings.
A great diversity is found between winter ranges in
different parts of the study area. All winter ranges are
classed 1'S or 2'S, and fall into one of four major types.
£late~Q§ ~ng ~~nil~ ~1QE§§~ Well vegetated plateaus or
gentle slopes with limited snow cover associated with deep
canyons, steep slopes, or cliffs for escape terrain, are
favored ranges and are heavily utilized. Many of these areas
are on the perifhery of mountain ranges where exposure to
prevailing winds keeps snow depths minimal. Soil is
relatively stable on these sites, and growing conditions for
forage plants are good. Ranges of this type are almost
always rated class 1 •
.§.lo£~.§ and ~g~al .§.E.Y.£§ ~i !~lin§.:. Sheep were
regularly observed utilizing slopes and lateral spurs near
treeline. Snow depths are greater here than in the type
previously described; however, these sites are not packed
hard enough to hinder movement or feeding. Feeding craters
were observed both above and below treeline in areas with
escape terrain always close at hand and, even in the trees,
visibility unobscured. Ranges of this type are rated class 1
or 2.
~lO£§§ ~Q §EY~§ associated with eroded ~!§~
Moderate numbers of sheep were observed-wintering-on slopes
or lateral spurs in association with eroded rock bluffs.
Snow depths on these sites are usually small due to exposure
to wind. Slopes are steep and often unstable, giving some
protection from predators. Habitat of this type can be seen
73
in various situaticns -including along river valleys and
high in alpine tundra basins. Small bluffs or benches
sometimes created areas on these slopes where stable soil
and better growing conditions resulted in better plant
growth. Willow may also occur at the base of these outcrops,
and is also utilized. Ranges of this type are class 1 or 2.
Hlah ridg~§ ~ng §!OQ~ This habitat type is the least
common of the fcur. Reduced snow depths as a result of
exposure to prevailing winds are always associated. Unstable
slopes and sparse vegetative cover are characteristic. High
elevations also tend tc restrict vegetative cover, thus
reducing the number of sheep these areas are able to
support. Most ranges of this type are class 2 with
occasional areas of class 1.
2. ~!!!!U!l~!: Ran~
Dall sheep summer range varies from high talus ridges
to low cliffs along streams. Sheep disperse from winter
ranges to areas not available to them in winter. Movement
during the summer is unrestricted and animals utilize large
areas limited only by proximity to escape terrain. Areas
having all the qualities of good sheep habitat, except for
the absence of escape terrain are not utilized.
Little is known about the location and characteristics
of lambing areas, although two areas along steep river
breaks in the carcajou Canyon map area have been reported
(Simmons, pers. ccmm.). Ewes are known to favor very rugged
habitat, and occasionally concentrate during the lambing
period.
The use of mineral licks is important, and ewe-lamb
groups are commonly seen in proximity to these licks. Ram
groups tend to use mineral licks somewhat less (Simmons,
pers. comm.). Several licks have been located in the
Carcajou Canyon maF area, but nothing is available for other
parts of the study area.
B. Populations
Four distinct populations of Dall sheep occur within
the study area. Separated by geographical location, Fhysical
isolation from other sheeF, or major habitat differences,
the four areas are -the Nahanni, Ram and Yohin-Liard area;
the Mackenzie Mountains; the Richardson Mountains; and the
British Mountains.
1. Na hanJ.!i ~]Sh ~.!!! PlmauL !Q.b.in=,LiY:g !!~llil~§
74
This area is the eastern limit of Dall sheep habitat.
The Nahanni Range and Ram Plateau are physically isolated
from ether areas of Dall sheep. The Yohin-Liard ranges are
somewhat removed from the main mountain complex; however,
some movement is speculated. An estimated 50 animals occupy
the Nahanni Range, with the bulk of the herd in the south-
central portion cf the area. Because of its precipitous
nature, the Ram Plateau was difficult to survey, but a
conservative estimate of the sheep population is 15-20
animals. Ten sheep were cbserved on the Yohin-Liard ranges
during summer surveys.
The Nahanni and Yohin-Liard ranges are mainly of
"slopes and lateral spurs at treeline" type winter range
with lesser amounts of "high ridges and slopes" type. These
habitat types were discussed in the previous section. The
Ram Plateau is a "plateau and gentle slope" type with steep
canyons falling away sharflY from flat tops. Some small
"lateral spurs", lccated on the north end of the plateau are
also utilized during the winter. All of these winter ranges
are exposed tc wind, and are kept clear of snow.
2. Mackenzie Mountains -------~-----
The Mackenzie Mountains are the most extensive range of
mountains in the study area, and have the largest pofulation
of Dall sheep. Sheep inhabit are~s varying from rough,
barren, precipitous terrain in the Backbone Range, to
gentle, well-vegetated plateaus in the carcajou River area.
All four types of wintering habitat are represented in this
region. The best wintering areas are "plateaus and gentle
slopes" and "slopes and lateral spurs at treeline" in the
carcajou canyon, Ncrman Wells, and Sans Sault Rapids
mapsheet areas. These sites are in a zone of light snowfall,
and exposure to prevailing winds helps keep snow conditions
shallow. The wintering areas within this region are actually
more extensive than in other regions, and consequently
larger groups of sheep inhabit them. In these areas of low
snowfall or soft snow cover, the animals are able to feed
and move freely.
The northwest portion of the Mackenzie Mcuntains
(Arctic Red River area} has poorer habitat of the "slopes
and spurs associated with eroded bluffs", "high ridges and
slopes", and "slopes and lateral spurs at treeline" types.
This area is much rougher, with unstable slope conditions,
and sparce vegetative cover. Group sizes are smaller.
75
Dall sheep are found in two areas in the Richardson
Mountains. About 500 animals inhabit the McDougall Pass -
Mount Goodenough area, and about 40 animals utilize river
canyons in the Doll Creek area of the southern Bichardsons.
The major wintering area for the Mount Goodenough group
is in the eastern pcrticn of the mountains north of
McDougall Pass. "Plateaus and gentle slopes", and "slopes
and lateral spurs at treeline" are the predominant winter
range types. High winds keep exposed plateaus and slopes
almost completely clear of snow. Feeding areas are in close
proximity to steep lateral spurs and canyons which provide
protection from fredators. There is a general movement
towards the west at least as far as Bell River during the
summer. Many areas of suitable habitat are not used,
however, due to lack of suitable escape terrain.
Limited information is available for the Doll Creek
group, but preliminary surveys suggest habitat is limited,
and is restricted to plateaus and slopes in close proximity
to steep stream canyons. Nothing has been recorded of summer
movements or distribution.
4. !!.£:!!:!§!! .[1.Q£ntain.§
About 50 to 75 sheep, part of the herd which extends
from the Brooks Bange in Alaska, inhabit the British
Mountains in the northern Yukon. The good wintering habitat,
mostly of the "slot:es and lateral spurs at treeline type",
is on the west side of the Firth River. Strong winds are
important in keeping small benches snow free, permitting
winter use.
Records indicate movement of animals from this area to
the Brooks Range, suggesting that this is the eastern limit
of sheep in that region.
5.3.4 Conclusions
All Dall sheep habitat is situated west of the
Mackenzie River. Habitat quality is not limited in the more
northerly latitudes. Winter range is considered the most
important habitat and sheep are often concentrated on these
ranges. All wintering habitat was rated class 1 or 2 and may
be broken into four major types; plateaus and gentle slopes,
slopes and lateral spurs at treeline, slopes and spurs
associated with eroded bluffs and high ridges and slopes.
Sheep disperse during the summer. Lack of precipitous escape
terrain in the Richardson Mountains seems to restrict summer
76
distribution of sheep.
Two lambing areas as well as several mineral licks were
reported on the Carcajou Canyon map area. Sheep, especially
ewes and lambs, tend to concentrate around mineral licks
during the spring and summer.
Four major populations of Dall sheep occur in the study
area: the Nahanni, Ram, Yohin-Liard group; the Mackenzie
Mountains group; the Richardson Mountains group; and the
British Mountains group.
5.3.5 Speculations on Impact
Since most Dall sheep range is in the western part of
the study area, well away from the actual proposed pipeline
route, the effects of a pipeline should be minimal. However,
in the Richardson Mountains, the proposed route passes very
near some important wintering areas, and pipeline activities
in this area could be very disturbing. Two phases of
pipeline activity must be considered, the construction phase
and the operation and maintenance phase.
A. Construction
Sheep fear both the sight and sound of aircraft, thus,
heavy use of aircraft in support activities at the time of
pipeline construction could have serious effects on the
local Dall sheep populations. Low-flying aircraft are more
disturbing than high-flying aircraft, and helicopters more
than fixed-wing, probably because the rotor system of a
helicopter emits higher and greater noise levels than does
the propeller cf mcst fixed-wings. Aircraft disturbance is a
problem with sheep at any time, but is especially so during
the winter period and at lambing time.
Gravel or fill removal from or very near sheep ranges
would likely have long-term effects on the population. The
use of noisy equipment or explosives in close proximity to
critical winter ranges or lambing areas could disturb the
animals enough that they would be forced to vacate these
ranges.
At present, sport and native hunting of sheep is light,
due to the inaccessibility of sheep range within the study
area. However, hunting by pipeline construction personnel,
native or white, situated in large camps near sheep range,
could result in disastrous overharvests.
77
B. Maintenance and Operation
The associated roads and cutlines that will be
established during pipeline construction will provide
greater access for native and sport hunters in the area. If
Dall sheep populations in the area are small, this could
rapidly result in an overharvest.
The noise from compressor stations may keep sheep away.
If located on or near an important winter range or lambing
area, abandonment of the area could occur with serious
results.
5.3.6 Recommendations
The most important features of Dall sheep range are
wintering areas, lambing areas, and mineral licks. Winter
range is critical, and animals tend to congregate in these
areas at that time. In the Richardson Mountains, sheep
occupy their winter ranges from approximately November 1 to
May 15. The winter period is slightly shorter in the
Mackenzie Mountains. Lambing begins in early May and
continues to mid-June, with the peak around late May. Use of
mineral licks begins in late May and continues until late
summer. Disturbance in these areas during their sensitive
times could result in reduction of the Dall sheep population
of the area.
1. Ai.££!:ill
It is recommended that the use of support aircraft
during pipeline construction be closely regulated. Flight
corridors and minimum elevations should be instituted, and
low level flight over winter ranges, lambing areas, and
mineral licks strictly prohibited. The construction and
operation of major helicopter pads or airstrips in proximity
to sheep range is not recommended. Low level flying for the
purpose of picture-taking should be discouraged. This causes
panic and stress in sheep, and can be extremely serious.
Harassment of this sort should be strictly prevented.
2. Gr~yg! ~!lQ !il! I~.!!LQ.!~!
The removal of granular material from areas of sheep
winter range would result in long-term habitat destruction.
3. g~sti!l9. £nd hg£.!1 gg!!i.E!!~i
Whenever possible, the use of heavy equipment and
78
blasting should be timed sc as to minimize disturbance while
sheep are on their winter ranges, mineral licks or lambing
areas.
Ccmpressor stations should not be located in close
proximity to winter ranges, mineral licks or lambing areas.
It is recommended
prohibiting huntir.g of
pipeline construction.
that regulations be established
sheep by personnel involved with
Table 4. A summary of possible effects a gas pipeline may have on Dall sheep.
Activity
Aircraft use in
support of construction
or operation of a
pipeline
Grave 1 or f i 11
remova 1 from or near
important ranges
Operation of compressor
stations near
important ranges
Blasting and use of
heavy equipment during
construction
Total pipeline
deve 1 opmen t
Sport and native
hunting from
construct ion camps
Potential Effects
Harassment by aircraft, part-
icularly helicopters, may cause
animals to leave winter ranges,
lambing areas or mineral licks.
Low-level flights may cause
sheep to expend additional
energy during critical periods.
The removal of soil material
from winter ranges could have
destructive effects on this
important habitat. Heavy
equipment used in extracting
material near winter ranges may
force sheep to vacate this
habitat.
The operation of a noisy
compressor station on winter
range, near lambing areas or
mineral licks could cause
abandonment to these habitat
components.
The loud noise associated with
construction equipment and
blasting in close proximity
to winter ranges, lambing areas
and mineral 1 icks, could force
animals to abandon these areas.
The increase in human population
occurring from the pipeline could
cause an increase in harvest of
Dall sheep. Small, isolated
sheep populations would be most
vulnerable to overharvest.
Hunting from camps located near
sheep ranges would cause an
increase in harvest. Smaller,
isolated sheep populations could
be seriously overharvested.
Magnitude
Large
Moderate
Moderate
Moderate
Moderate
Large
79
Table 4. Cont 1 d.
Activity
Increased access
caused by pipeline
construction and
operation and additional
hunting pressure
Destruction of habitat
by constructing a
pipeline across winter
range
Potential Effects
Roads and cutlines necessary
in the construction and
operation of a pipeline would
create greater access to sheep
ranges for sport and native
hunters. Overharvest may result
from excessive hunting.
The loss of habitat incurred by
constructing a pipeline on winter
range could reduce the size of
this habitat.
Bo
Magnitude
Large
Moderate
81
5.4 GFIZZLY BEAR
5.4.1 Introduction
Except for a few scattered observations, and very
general distribution maps, very little was known about
grizzly bears within the study area. Since grizzly bears are
not restricted to specific habitat types, information was
collected on distribution, relative abundance, and location
of den sites. This was then used to delineate, classify, and
describe broad habitat units. Implications and
recommendations were made giving the researchers• views on
possible problems which may arise as a result of pipeline
construction activity.
5.4.2 Methods
Preliminary Office Activity
Very limited information on grizzly bears was available
for the study area. General distribution was determined from
incidental sightings, and reports of den site locations.
Numerous sightings and dens were recorded by Renewable
Resources Consulting Services Ltd., while doing caribou
surveys in the Northern Yukon in 1971. However, few or no
data were available for the rest of the area.
Field Activities
Aerial surveys for grizzlies were based on Fort
Simpson, Norman Wells, Inuvik, and Old Crow. Extensive
aerial surveys were conducted April 18, 1972 to June 12,
1972, the approximate time bears emerge from winter dens.
Aerial surveys were conducted to collect information on den
site locations, relative abundance and distribution.
A Cessna-185 and a De Havilland Beaver were used for
general reconnaissance flights. When fresh grizzly bear
tracks or dens were located, a Bell-206 helicopter was
chartered to back-track and observe den sites. Field notes
were taped, and all observations were plotted on 1:250,000
scale maps. Incidental sightings from other wildlife surveys
were also recorded.
Analysis and Final Mapping
Grizzly bear units are generally very large, determined
mainly by general physical landforms, broad vegetation
82
zones, and relative abundance of bears. Descriptive
narratives of these units are, consequently, also general,
outlining physical features, vegetation compositicn, and
significant attractions or limitations.
Grizzly bear habitat is very difficult to classify, as
bear distribution cannot te directly related to specific
habitat type. General topography, landforms, and vegetation
types were considered and correlated with po~ulation
abundance and distribution as determined from past records
and field surveys. Availability of good food sources was
also considered. Delineation and classification of units was
done on a relative basis, and in places information was
taken from a known area and extrapolated to areas where
little was known.
Due to the generalizations made in classifying grizzly
bear habitat, this study cannot be considered a true
detailed habitat evaluation. It does give a modified
distribution map delineating broad habitat units, the
relative abundance and densities of grizzly bear
populations, important use areas, and brief discussions of
habitat qualities and limitations.
Class 1
A class 1 unit has no obvious factors which may limit
grizzly bears. These units possess the habitat requirements
of gocd interspersion cf landforms, suitable vegetation
types, abundant food sources and especially, available
denning habitat. Relatively high numbers of bears were
recorded utilizing these areas.
Class 2
A class 2 unit has minor limitations for grizzly bears.
These areas possess most of the requirements essential in
supporting bears but lack cne or more qualities, making them
less than optimum. A moderate number of bears were cbserved
in class 2 areas.
Class 3
A class 3 unit has moderate to severe
grizzly bears. These units lack qualities
grizzly bear habitat. Only occasional
recorded in class 3 units.
Class 4
limitaticns for
essential to good
sightings were
Class 4 units have
and are considered poor
observations of bears in
animals may pass through
83
severe limitations to grizzly bears
habitat. Although there were no
class 4 units, occasional transient
these areas.
5.4.3 Results and Discussion
Spring surveys were conducted to obtain information on
relative abundance of bears, and location of den sites.
Concentrated effort at this time, when bears are emerging
from their dens, proved successful, in that tracks as well
as bears could be cbserved and recorded. Unless the tear had
just recently emerged from its den, it was very difficult to
re-trace tracks to the den site. The species of the bear
cannot be determined from tracks; only by locating the
individual can this be confirmed. Numerous grizzly and black
bear sightings were recorded while conducting surveys for
other species. This information assisted the program by
giving a record of year-round distribution of bears.
Grizzly bears are cmnivorous, with food preferences
ranging from roots and berries to ground squirrels, fish,
caribou and moose. The availability of food seems to
determine grizzly bear distribution and abundance more so
than does specific habitat types.
Preliminary studies in the northern Yukon suggest adult
male bears have a very large home range, and appear to move
with, or perhaps follow, the migrating barren-ground
caribou. Grizzlies have also been reported preying on new-
born calves on the caribou calving grounds. It is scmetimes
difficult to assess whether good food sources are available
or not, but this is the major factor which may limit grizzly
bears.
Landform, topography, vegetation type, and apparent
food sources were factors used in describing grizzly bear
habitat. Throughout the scuth and central portion of the
study area, grizzly bears prefer rough, broken terrain as
found in mountain regions, possibly as a result of the wide
variety of vegetation types available. Areas of low relief,
continuous bog or homogeneous forest cover offers a poor
choice of food, and are little used. No doubt observer error
would be greater in the forested regions as compared to the
semi-open mountain areas, resulting in some bias in
estimates of relative abundance. However, it is interesting
to note that many tlack bears were observed in the Boreal
Forest regions, whereas grizzlies were more common in the
mountains, suggesting that they prefer these regions. In the
84
northern portion of the study area, grizzlies utilize low-
relief~ open-tundra zones~ such as the Yukon Coastal Plain,
Richards Island, and the Tuktoyaktuk Peninsula. The taiga-
tundra transition zone receives some use. The mountainous
region of the northern section contains the highest number
of grizzly bear sightings in the study area.
Denning areas are an important feature of grizzly bear
habitat. Records of known sites in the Old Crew area
indicate that bears tend to use the same dens year after
year. This may be especially true in regions of shallow
active layers.
Denning areas
numbers of den sites
usually associated
streambanks.
are difficult to locate,
have been recorded. Known
with mountain slopes,
and small
sites are
hills, or
Because of the non-specific nature of grizzly bear
habitat, habitat units are large and narrative descriptions
very general.
5.4.4 Conclusions
Distribution and abundance of grizzly bear seems to
depend more on availability of food than on specific habitat
types. Information collected in the northern Yukon suggests
that adult male bears have a very large home range, and
appear to follow the migrating barren-ground caribou.
Landform, topography, vegetative type and apparent food
sources were considered in delineating and describing
grizzly bear habitat.
Throughout the south and central portion of the study
area, grizzlies prefer the rough, broken terrain of the
mountains and hilly regions. Areas of low relief, continuous
bog, or homogenous forest cover offer little choice cf food
and receive little use. Observer error was greater in
heavily-forested regions. Black bears were sighted more
frequently in the Boreal Forest regions.
Grizzly bear were more numerous in the northern portion
of the study area, utilizing low relief tundra areas such as
the Yukon Coastal Plain, Richards Island, and the
Tuktoyaktuk Peninsula. Grizzly bear sightings were most
numerous in the mountain regions of the northern Yukon.
Den sites are an important factor in considering
grizzly bear habitat, and records indicate long-term use of
85
individual dens. Dens are difficult to locate, and only a
few dens have been recorded. Known sites were usually found
associated with mountain slopes, hills or streambanks.
s.u.s Speculations on Impact -Grizzly Bear
Grizzly bear distribution along the pipeline corridor
varies from almost nil in some southern sections to high
densities in the northern and mountainous regions. The
amount of bear disturbance and the occurrence of man-bear
interaction will probably increase as construction programs
move into habitat supporting higher numbers of grizzlies.
In the past, improper garbage disposal has led to
numerous problems with grizzlies, ranging from raided
cookhouses to severe maulings. In most cases this has
resulted in the destruction of the bear or bears. Effective
garbage and sewage disposal systems are vital and should
reduce the bear conflicts of this nature.
Denning sites are thought to be one of the most
important parts of grizzly bear habitat, especially in zones
of shallow active layers. Bears have been recorded using the
same dens continually for many years. Disturbance or
elimination of denning sites could have a drastic effect on
the bear population in some locations.
The chance of man-bear confrontations could
near den sites, as females with cubs reportedly
home ranges and usually travel within 10 to 15
their winter dens.
be large
have small
miles of
Pipeline construction activities near an abundant
grizzly bear food source, such as a caribou calving ground,
migration route, or a char stream, would also escalate the
chances of man-bear interactions.
Grizzly bears are disturbed by low-flying aircraft,
particularly by helicopters. The amount of harassment and
the effect it has on grizzly tears can be variable and is
largely unknown. Time of year, amount of cover, terrain, sex
and age class of the tear, and type of aircraft are just
some of the factors involved on the degree of such
disturbance.
5.4.6 Speculations on Impact -Black Bear
Black bears are distributed in varying densities along
86
the entire pipeline corridor, with the exception cf tundra
areas in the extreme northern sections. Although the black
bear is not considered as ferocious or unpredictable as the
grizzly, it can become a serious nuisance when attracted to
construction camps. As with grizzlies, black bears are
attracted to camFs with poor garbage or sewage disposal.
Little is known of denning requirements of the black bear in
northern Canada. Since black bears are usually in or near
forest cover, the effect of aircraft disturbance wculd not
likely be as great as it would be for grizzlies.
5.4.7 Recommendations-Grizzly and Black Bears
Grizzly bears in the southern sections of the Fipeline
corridor have been reported to begin emerging from dens in
late March. Adult tears were recorded "out" in northern
areas as early as April, and most females and cubs are
thought to have emerged by mid-June. The males are normally
the last to den in the fall and are usually "in" by mid-
November. During the period bears are out of their den, the
following recommendations are suggested if bear problems are
to be kept minimal:
1. Proper incineration or disposal
sewage is an absolute necessity. Oil
incinerators should be installed in all
daily.
of garbage and
or gas-fired
camps and used
2. camps should not be located in close proximity to
known dens during the period bears are "out". Information on
den sites at present is limited, but there is suggestion
that denning may be scmewhat concentrated on specific
landforms. Even a "clean camp" could be investigated by
bears that normally frequent the area. Sows and cubs would
very likely visit camps near dens because they tend to
utilize a relatively small home range.
3. Camps should be equipped with some form
devices such as exploding shotgun shells, or
These could be used to frighten bears that have
camps. The development of a chemical that will
repel bears from camps would be invaluable.
of scaring
fla:re guns.
apfroached
effectively
4. A firearms restriction for all personnel involved
in pipeline activities should be imposed, with the exception
of one rifle per camp that would be used in cases of
absolute emergency. This regulation would virtually
eliminate any form of hunting from these camps.
87
5. Strict regulaticns concerning aircraft should be
imposed in some locations of the pipeline route. Continuous
and intense aircraft use involved in pipeline activities is
certain to have some effect on grizzly bears, particularly
in tundra regions supporting high populations.
With the influx of people expected with pipeline
activities, the sport hunting of grizzly bear is likely to
increase, especially in the northern portion of the
corridor. Although there seems to be large numbers of bears
in some areas, little is known about the productivity of
these bear populations, and thus, an increase of sport
hunting should be closely regulated to prevent an
overharvest.
88
Table 5. A summary of possible effects a gas pipeline may have on grizzly bear.
Activity
Improper garbage and
sewage disposal at
construction camps
Location of camps in
high density areas of
grizzly bears and
black bears
Firearms in construction
camps
Intensive low-level
aircraft use in high
density bear habitat
Camps located near
grizzly bear dens
Destruction of den
sites during extraction
of granular materials
Increased access and
hunting of grizzly
bears
Potential Effects Magnitude
Bears are attracted to camps Large
with poor garbage or sewage
disposal systems. Grizzly bears
are potentially dangerous when
feeding around garbage and as
such are often shot.
Bears are often attracted to Moderate
camps out of pure curiosity
and by strange odours.
Grizzly bears have often been Large
indiscriminately killed by
personnel in camps for no
justifiable reason. Hunting
from large camps, particularly
in high density areas on tundra
zones may cause a drastic reduction
in the bear population.
Intensive aircraft use on tundra Moderate
areas could force bears to
vacate the area.
Camps located near den sites would Moderate
increase the chance of man-bear
conflicts as female-club groups
have a small home range.
Destruction of winter dens of Large
grizzly bear could force these
animals to locate in other areas
of lesser quality habitat.
Due to the increase in human Large
population and sport hunting
activities associated with
pipeline development, overharvest
of grizzly populations might
occur. Roads and cutl ines
constructed by the pipeline
would increase access for
hunters.
89
5.5 ARCTIC FOX
5.5.1 Introduction
Since arctic fox range throughout the Arctic tundra
zone, and because fox populations are subject to cycles, the
object of the. study was to locate and evaluate important
habitat units. Efforts were concentrated towards locating
maternal den sites and correlating their abundance with
general physical features and vegetation types. Consultation
with trappers and fur dealers assisted in delineation of
winter distribution and in habitat classification.
5.5.2 Methods
Preliminary Office Activity
Other than general distribution maps, very little
scientific information was available on arctic foxes within
the study area. Publication on other studies of arctic foxes
were reviewed and assisted in outlining an effective field
program.
Field Activities
surveys were conducted out of Inuvik, N.W.T., and a
field camp near the Firth River. A Cessna-185 and Eell-206
Jet Ranger were used with two observers (one on each side)
equipped with 1:250,000 scale maps, tape recorders, and
cameras. Selected areas were flown systematically at
altitudes of 300 to 500 feet.
Two surveys were conducted. The first was in early May
when female foxes prepare their dens for whelping. It was
surmised that the re-digging or cleaning out of dens would
leave soil materials on the surrounding snow, which could be
observed from the air. The second and most successful survey
using a Bell-206 helicopter was in early July, using the
method described by Macpherson (1969).
Observers watched for lush, green patches of vegetation
which occur around den sites. Once a potential site was
located, the helicopter landed, and the site was
investigated. Photographs were taken of each den, and a
brief description made of site features. All locations were
recorded on 1:250,000 scale maps.
In the Herschel Island and Tuktoyaktuk regions, local
90
trappers assisted researchers in guiding them to den sites.
Limited information was gathered from interviews with
trappers and a local fur buyer at Tuktoyaktuk.
Analysis and Final Mapping
Since the entire Arctic tundra zone can be utilized by
arctic foxes, it was decided that relative abundance of dens
would be the main criterion used in classifying arctic fox
habitat. Information from trappers, landforms, and
vegetation types were used to delineate and describe habitat
units.
Arctic fox range is restricted to the Arctic tundra
regions of the study area. The tundra zone includes the
Yukon Coastal Plain, the lower Mackenzie Delta, the
Tuktoyaktuk Peninsula and a large area extending from the
Eskimo Lakes to the lcwer Anderson River. In classifying
arctic fox habitat, data combined from various sources were
used. Basic landforms, vegetation types, distribution and
trapping records were examined. These were correlated with
observations on active dens and general habitat information
collected during the 1972 field season. Due to the lack of
past information and the difficulties encountered in
evaluating arctic fox habitat, ratings were assigned on a
relative basis. In some cases extrapolations were made to
areas of limited information. Areas with a large number of
active dens were given the highest rating; while inland
areas used only occasionally by winter transients were
considered poor.
Although difficult to assess on a land classification
basis, the presence of good food sources is very important
to arctic fox survival.
Class 1
A class 1 unit has no obvious factors limiting arctic
foxes. These units possess the qualities of suitable soil
composition necessary in denning, abundant food supplies,
and preferred vegetative cover. High numbers of fox dens
were recorded in class 1 areas.
Class 2
A class 2 unit has minor
These areas have most of
foxes but lack quality,
were recorded in mcst of
foxes often winter in
the
making
these
these
limitations for arctic foxes.
requirements important for
them less than optimum. Dens
units. A large number of
areas during peak poFulation
91
years.
Class 3
A class 3 unit has moderate to severe limitations for
arctic foxes. These areas lack qualities essential to good
fox habitat. Only occasionally have foxes been recorded in
these areas, usually during winters of peak populations.
Class 4
Class 4 units have severe limitations to arctic foxes.
Some class 4 units, in clcse proximity to good habitat, may
receive an occasional transient during high pofulation
years.
5.5.3 Results and Discussion
Evaluation of arctic fox habitat is difficult in that
fox populations are cyclic, and the animal cannot be
censused easily. The main criterion used in assessing arctic
fox habitat in this study was the relative density of
maternal dens on potential fox range. Den sites are re-used
for many years. Areas which did not have a large number of
dens, but are used during the winter period, were also
evaluated.
surveys in
after a short
not be located
drifting snow
areas.
May were not successful and were terminated
trial period. Freshly excavated sites could
from the air, probably due to the high and
conditions which were common in open tundra
The second set of surveys were conducted in July when
the vegetation was mature and observations of den sites
would be easiest. The lusher vegetation around den sites is
due to added soil fertility as a result of fecal droppings
and discarded food scraps.
Ground squirrel dens and fox dens are very similar in
appearance, and clcse examination was required to positively
identify sites. High populations of ground squirrels were
encountered along the Yukon Coastal Plain and the
Tuktoyaktuk Peninsula.
The greatest concentration of arctic
in the Herschel Island mapsheet area.
variety of sites, including sand dunes
frost heaves, and the banks of rivers,
fox dens was found
Dens occurred on a
in river deltas,
lakes and streams.
92
Crests of low hillE were also favored. On the Tuktoyaktuk
Peninsula, all dens located were in sand dunes along the
north coast. These were extremely difficult to observe due
to the low fertility and FOOr vegetative growth which occurs
in sand areas. Nearly all den sites were in a position to
command a good view of the surrounding area, and all were
near fresh water. Dens were usually dug in porcus soil
materials.
Colored or red foxes are common throughout much of the
tundra region, and are most abundant in the shrub-tundra
transition zones. Several colored fox dens were located, and
a small overlap between the ranges of colored and arctic
foxes was noted. Arctic fcxes prefer to den in regions of
low vegetation with little or no shrub thickets. All arctic
fox dens were in the open on relatively low relief sites,
whereas colored fox dens were often found on steep banks and
hillsides.
Local trappers reported that in years of high
population, arctic foxes come in off the sea ice to the
coastal areas. Although large scale movements of arctic
foxes have not been scientifically documented, cases of
individual foxes mcving several hundred miles have been
recorded. Movement of this sort probably occurs only in the
winter when food supplies are low. The Hudsons Bay Company
fur-buyer in Tuktoyaktuk stated that the 1971-72 trapping
season was the best in years. The coastal areas are favorite
trapping sites for residents of Herschel and Tuktoykatuk.
5.5.4 Conclusions
The greatest concentration of arctic fox dens was found
in the Herschel Island map area. Dens occurred on a variety
of sites, including sand dunes, frost heaves, and the banks
or rivers, lakes and streams. Nearly all den sites were in a
position to command a good view of the surrounding area, and
all were near fresh water. Dens were usually dug in porous
soil materials.
Colored or red foxes inhabit tundra zones, but are most
abundant in the shrub-tundra transition zones. Arctic foxes
prefer to den in regions of low vegetation with little or no
shrub thickets. Nearly all arctic fox dens were in the open
on relatively low relief sites, whereas, colored fox dens
were usually found on steep banks and hillsides.
5.5.5 Speculations in ImFact
Arctic fox range extends over the whole Arctic tundra
zone, of which the study area covers only a small part. The
mapsheets which have arctic fcx range are:
Demarcation Point (117C), Herschel Island ( 117 D), Blow
River (117 A), Aklavik (107 B), Mackenzie Delta (107 C),
Stanton (107 D), and Cape Dalhousie (107 E).
As the proposed pifeline route crosses several areas of good
fox habitat, the possible effects of this development must
be considered.
One of the most important requirements of arctic fox
habitat is denning sites. Foxes prefer to den in areas of
fine well-sorted silt, sand or gravel. Extraction of
granular material for pipeline construction could result in
habitat degradaticn by reduction of denning sites. High
density denning areas, such as those on the Herschel Island
mapsheet, would be farticularly vulnerable. This is
especially so, as it is known that dens are used fer long
periods of time. It has been estimated that some dens in the
Eastern Arctic have been in continual use for over 200 years
(Macpherson, 1969).
Harassment by aircraft, heavy equipment, or explosives
could result in females abandoning their young, therefore
caution should be exercised during the whelping and denning
period from mid-May to early September. Arctic foxes often
scavenge during winter periods and are easily drawn to raw
garbage. During the winter, hungry foxes show little fear of
man, and will most certainly be attracted to camps. This is
not desirable, as foxes are known carriers of rabies.
5.5.6 Recommendations
1. Proper incineration or disposal of garbage and
sewage is an absolute necessity if foxes are to be kept away
from camps. Oil or gas incinerators should be installed in
all camps and used daily.
2. The use cf non-toxic chemicals to repel foxes from
garbage disposal sites would be invaluable.
3. Restriction of firearms for all personnel involved
in pipeline activities shculd be imposed. This should apply
to native and white employees alike, thus eliminating
hunting around the camps.
Extraction of gravel at or in close proximity to dens
93
94
is not recommended. Destruction of den sites and disturbance
of active dens would seriously limit foxes.
5. To minimize harassment by aircraft,
recommended that air corridors be incorporated.
it is
95
Table 6. A summary of possible effects a gas pipeline may have on
arctic foxes.
Activity
Improper garbage and
sewage disposal at
construction camps
Location of camps in
high density areas for
arctic fox
Intensive low-level
aircraft use in high
density fox habitat
Destruction of den
sites for granular
materials
Potential Effects Magnitude
Foxes are attracted to camps Large
with poor garbage or sewage
disposal systems. Foxes are
known to be carriers of rabies.
Foxes are often attracted to Moderate
camps out of pure curiosity
and by strange odors.
Aircraft harassment in proximity Moderate
to arctic fox maternal dens may
cause abandonment of the young.
Destruction of maternal den sites Large
of arctic fox could force these
animals to locate in other areas
of lesser quality habitat.
5.6 BEAVER AND MUSKRAT
5.6.1 Introduction
Justification
Within the framewoLk of Northern Pipeline Studies,
beaver and muskrat populations may be viewed in terms of two
sets of interrelated values. Features that directly involve
human interactions may be thought of as social values, while
those relating to the interactions of each species with its
natural surroundings are environmental values. Both sets of
values are difficult to quantify but demanding of attention
if wildlife is to be a part of land-use planning programs.
The role that beaver and muskrat populations play in
shaping the life-style of northern peoples is quite diverse
but influenced strcngly by economic factors. On the fur
market, beaver and muskrat compete locally with upland
forbearers, mink, marten, and lynx. Although time of harvest
differs for the two groups, the effort expended on
harvesting either group is in part dependent on current
market values. Of much greater significance is the tendency
for beaver and muskrat poFulations to achieve high densities
within suitable aquatic environments. Thus trappers are able
to establish semi-permanent base camps and collect large
numbers of furs within a short time period. Because beaver
and muskrat achieve and retain pelt primeness through late
winter and spring months, trappers may take advantage of the
longer periods of daylight and higher temperatures to
accomplish the harvest. Entire families may participate in
the spring hunts which have become a tradition within
northern communities. A further feature of beaver and
muskrat harvest prcgrams, which tends to de-emphasize market
values, relates to food value of the animal carcass. Most
newcomers to the rat camps are pl~asantly surprised by the
palatability of freshly caught muskrats which are so
important in the diet of native trappers.
From an environmental standpoint, beaver and muskrat
activity often has a readily-apparent influence in shaping
and modifying aquatic ecosystems. Changes in plant
succession that are evident above beaver dams are
complemented by modified downstream flow regimes; in both
instances the trend is toward more permanent aquatic
habitat. Muskrats fall prey to one or more species of
mammals, birds, or fish throughout the year. As such, their
positicn on the fcod chain can be vital to the perpetuation
of specific communities.
97
Objectives
This brief overview seeks to place in perspective the
kinds of factors asscciated with beaver and muskrat
populations within the study area. Certainly the range is
far too broad tc allow extensive investigation of all
relationships within the allotted time period.
Identification of habitat and description of habitat types
appears to be a logical starting point in providing
information for land-use planning programs or setting the
stage for more detailed research.
Preliminary identification of beaver and muskrat
habitat within the Mackenzie Valley and northern Yukon was
facilitated in part by recognition of current and
traditional trapping areas throughout the corridor. Through
aerial surveys of representative wetland and stream
complexes, additicnal areas of occupation were located and
delineated. Classification of habitat followed as an attempt
to comFare physical attributes of identified habitat in
terms of known requirements of beaver and muskrat
populations.
5. 6. 2 Methods
Literature Review
Literature searches were conducted during the fall and
winter of 1971-72 to Frovide project personnel with some
insight into the landscapes and communities present within
the study area. Beaver surveys carried out by c.w.s.
personnel after 1948 were particularly applicable to the
furbearer program. Personal interviews were held with
scientists who have been, or are, conducting research on
aquatic species in the Mackenzie area. Field officers of the
Northwest Territories Game Branch were contacted during
preliminary field trips. Information requested during these
interviews centered on beaver and muskrat population
distribution, limiting factors, and intensity of harvest
operations.
Preliminary Mapping
Major wetland regions and drainage systems were
outlined on 1:250,000 National Topographic Series maps.
These preliminary boundaries were established on a basis of
geographic proximity, surface area and shoreline
configuration of lakes or ponds, and size or channel form of
stream systems.
Landscape components, particularly the resultant
features of continental glaciation, were identified through
reference to surficial geology maps supplied by the
Geological Survey of canada and the Canadian Forestry
Service. supplementary material included aerial photography
and Forest Management Institute cover maps.
The next step was to group wetlands and stream systems
into distinct units on the basis of gross outward
similarities as dictated by their geologic origin and
subsequent development. Units at that point were represented
by geographically distinct groups of deltaic, oxbow,
meltwater channel, glacial lacustrine, morainal plain, or
bedrock lake basins and associated streams. Within these
units sample sites were selected for field surveys.
Field Surveys
Immediately before spring breakup, muskrat pushup
surveys were conducted from fixed-wing aircraft (Cessna-185,
Beaver) to determine current distribution and relative
abundance of the species within the various units. Efforts
were concentrated in the higher density wetland areas where
muskrat populations were generally known to occur. In this
regard it was assumed that if construction activity impinged
on wetlands there could be a much greater overall impact on
muskrat populations in high density wetland complexes than
in isolated and individual lakes and ponds. It should be
noted that the same assumption does not necessarily hold
true from a strictly envi~onmental standpoint.
During the summer months aerial surveys were continued
to obtain a more detailed picture of types of terrain,
vegetative communities, lake and stream shoreline
development, water depths, and evidence of muskrat o~ beaver
populations. Whenever possible two observers accompanied
each flight, although useful results were obtained by one
observer assisted by the pilot. Flight altitude vas kept as
low as weather and terrain conditions allowed, usually 300-
600 feet above ground level. Observers used portable tape
recorders and flight-line checkpoints to document
observations in flight.
In mid-September, beaver surveys were conducted within
representative portions of the established units. Flight
lines were generally established along stream systems and
lakes to take advantage of readily apparent landmarks, but a
few grid patterns were flown over high-density wetland
units. Records were kept of all observations of current or
past beaver activity, including lodges, food caches, or
99
dams.
Classificaticn
After field notes and population data had been
transcribed and compiled, unit boundaires were adjusted to
accommodate specific habitat units. Each unit was given a
classification based on its relative importance in terms of
beaver and muskrat.
5.6.3 Results
An atlas* of topographic maps outlining beaver and
muskrat habitat within the study area provides the basic
results of 1972 field programs. Each landscape unit has been
assigned a classification; the classification system has
been explained, and a few illustrations of representative
areas are included. A short summary is incorporated within
this report to focus attention on geographic areas of better
quality habitat.
5.6.4 Discussion
Limitations
Within the study area, beaver and muskrats can
generally be found wherever the basic habitat requirements,
including suitable food and shelter, are available. The
success of each species, as judged by its ability to reach
higher density levels, is a direct function of the degree to
which these requirements are met. Optimum environments,
imposing few stresses on the population, ultimately result
in a harvestable surplus.
Classificaticn
several factors must be kept in mind when examining, or
attempting to extrapolate from, the habitat classification.
Both species, but particularly muskrats, are known to
exhibit marked fluctuations in population densities in more
southern regions. Possibly the same factors responsible for
these fluctuations influence populations within the study
area. Management personnel are well aware of decimation of
beaver populations in the Mackenzie region as a result of
excessive harvest programs. Thus, populations observed
within a specific area at any given time do not necessarily
provide a reliable picture of habitat quality. This problem
is compounded by the requirement that census programs are
*See note in Table of Contents
100
based on interpretation of secondary indicators. Lodges,
bank dens, dams, food caches, pushups, runs, and vegetation
cuttings are the otservable indicators of beaver or muskrat
activity, and each provides a degree of variability in
numbers of animals involved.
From a positive standpoint, indications of current or
past populations, as compared to no occupancy indicators,
provide a base from which to continue evaluations of the
physical components of a given aquatic environment. A few
examples will serve to illustrate the use of population data
in achieving a habitat classification.
Records from spring surveys on the Old Crow Flats
showed two lakes, in close proximity, one having an
abundance of muskrat pushups, the other apparently barren.
Subsequent ground checks after breakup showed the barren
lake to be very shallow, turbid, and nearly devoid of
aquatics, while the lake supporting muskrats was deeper,
clear, and producing an atundance of aquatics.
Within the Mackenzie Delta, very few active beaver
colonies were recorded during the study period, yet many
lakes and channels provide suitable banks for denning and
there is an abundance of available food species. Harvest
records and previous surveys indicate a good distribution of
beaver through the Delta in past years. contrary to current
population indicators, potential habitat does indeed exist
within this complex.
A third example is found in the many lakes occupying
the northeast portion of the Arctic Red River mapsheet. The
evident lack cf beaver activity in this area can be related
to shallow gravelly shorelines and extremely limited
deciduous tree cover. Under those conditions it is probable
that beaver could exist only on a temporary or transient
basis.
In all cases the habitat value or class, attached to
each landscape unit and denoted by a numerical scale from
one through four, Fresents a subjective summary of available
information. No rigid formulas were developed to reduce
subjectivity because the vast majority of input from field
studies is of a descriptive nature.
5.6.5 Potential Construction Impact
The Factors
101
Factors associated with construction programs, which
may have a bearir.g on beaver and muskrat populations, fall
into two broad categories. First there are the activities
resulting in habitat modification which can have both direct
and indirect influences on populations. A second category
includes those factors initiating behavioral responses, and
the influences of man, as the ultimate predator, on muskrat
and beaver populations. The former encompasses alteration of
water regimes (both timing and volumes), introduction of
sediment loads, introduction of foreign sutstance,
modification of forest fire effects and removal of riparian
cover. The latter includes audio-visual disturbances and
harvest programs subsequent to improved access to favorable
locations.
The Environment
Stream complexes and standing water bodies within the
study area are intimately associated, particularly so in
terms of beaver and muskrat habitat; however, the two
aquatic environments may respond quite differently to any
particular landscape disturbance factor. Also, the extent to
which a disturbance factor may exert its influence on each
aquatic environment will depend largely on the position of
such activity within any given drainage basin. It is
unlikely that moderate alterations of downstream channels
will have appreciable effects on headwater lakes; likewise,
downstream lakes may serve as buffer zones to temporarily
offset the influence of upstream activities. The measure of
"uniqueness" inherent tii thin the particular aquatic
environment, or attributed to its location within the
drainage basin, facilitates separation of standing water
habitat and flowing water habitat in the following
discussion.
The Relationship
A (1) Standing Water Bodies; Water Level Alterations
a. Complete Drainage.
Complete drainage of a lake or pond usually implies
total loss of current populations of muskrats and beaver and
available habitat.
b. Partial Drawdown.
Through much of the better quality standing water
habitat, depth is a critical factor to overwintering beaver
and muskrat populations. Drawdown could allow frost levels
102
to penetrate to and into the substrate, effecting winter-
kill. Drawdown in late fall, after overwinte~ing dens and
lodges are established, wculd invariably result in direct
mortality. In specific instances reduction of wate~ levels
could be instrumental in promoting the establishment of
emergent vegetation. This would apply primarily to deep
lakes, with narrow poorly developed shorelines, such as
occur within many glacial meltwater channels. The benefits
gained in terms of increased emergent vegetation would vary
directly with the surface area exposed by drawdown and the
subsequent stability of water levels.
c. Flooding.
Temporary high water levels and resultant flooding of
onshore communities is initially beneficial to many aquatic
systems through addition of organic nutrients. However, if
the timing and duration of flooding does not closely
approximate natural seasonal fluctuations the over-all and
long-term effects will likely result in poorly developed
aquatic and shoreline plant communities. Edge effect,
defined as the tendency toward greater variety and density
of organisms in the boundary zone between communities, can
be significantly mcdified by flooding. Landscapes exhibiting
a high degree of interspersion of water and land p~ovide a
favorable edge effect in terms of beaver and muskrat
populations (i.e. a high ratio of shoreline to surface
area). Inundation cf inte~vening land surfaces essentially
reduces the shoreline-surface area ratio and results in a
less favorable edge effect. The converse may be t~ue for
individual lakes or ponds within areas of low relief.
Flooding of proximal, low-lying terrestrial sites can
enhance the edge effect and create new habitat for aquatic
species. Generally flood effects must be evaluated in terms
of each individual set of landscape features.
A(2) Standing water Bodies; Sediment Load Alterations
The influx of sediments into standing waters normally
hastens the aging Frccess through a simple filling-in of the
basin. Since optimum habitat for both beaver and muskrats
lies somewhere between the deep water lakes and the more
eutrophic shallow lakes, the addition of sediment loads must
be evaluated accordingly. For those lakes currently occupied
by beaver and muskrat populations, sedimentation, on a large
scale, probably imFlies alteration of aquatic plant
communities and reduction of available overwintering
habitat.
A ( 3) Standing Water Bodies; Introduction of Foreign
103
Substances
Within northern latitudes, under the influence of long
periods of low temferature, aquatic systems must maintain a
rather delicate balance. As such, the introduction of
foreign substances presents a potential for extensive and
long-lasting effects. Foreseeably those substances
associated with construction activity and appearing
detrimental to many aquatic systems, and consequently to
muskrat and beaver populations, are fuel and lubricating
oils, and water-borne toxic chemicals. It is beyond the
scope of this paper to discuss the ramifications of oil
spills with regards to aquatic systems at large. It is
noteworthy that oil has a direct effect on aquatic
forbearers in causing matting of the dense underfur with
subsequent loss of buoyancy and insulation.
A (4) Standing Water Bodies; Changing Fire Regimes
Fire has historically played an important role in
beaver ecology throughout the Mackenzie Valley. Inasmuch as
construction activity will alter the potential for fire
effect (i.e., imfroved access will increase potential for
man-caused fires and alternately provide for better fire
control) , it must be included for consideration in any
impact assessment. The greatest direct influence of fires on
standing water habitat involves interruption of plant
succession patterns on immediate uplands. Much greater
indirect effects can be realized through the influence of
fire on the drainage basin as a whole.
A (5) standing water Bodies; Removal of Riparian cover
Vegetative communities along lake shorelines serve an
extremely important function in fostering bank stability,
protecting open waters from wind effect and retaining snow
cover during winter months. Some terrestrial plants,
particularly deciduous shrubs, are a major food source for
resident beaver populaticns. While selective removal of
mature trees can promote development of successional shrubby
species, complete removal of riparian cover must be viewed
as detrimental to the aquatic community.
B (1) Stream Complexes: Water Level Alterations
a. Complete Diversicn of Flow.
On headwater streams complete diversion of flow will,
of course, eliminate beaver habitat. The effect will be
directly realized in downstream areas until optimum flows
104
are regained through convergence of subsequent tributaries.
It is important to note that stream systems tend tcward a
dynamic equilibrium with the landscape (i.e., channel form,
vegetative associations), therefore alteration of flow
regimes will be expressed in a variety of ways throughout
the basin.
b. Partial Reduction of Flow or Change of Regime
Within the stream system, beaver attempt to obtain
optimum and stable water levels through construction of
dams. Any changes in volume or timing, beyond the caFability
of the dam to maintain cptimum depths, will result in
mortality or emigration. Stream flow regimes during the fall
and winter are particularly critical to beaver and muskrat.
Changes in water levels during that period could Iestrict
access to critical winter food supplies.
c. Flooding
Again, timing becomes critical to beaver poFulations.
Periodic spring flcoding is tolerated and favored where it
perpetuates the stream side willow-alder communities. At
this time beaver are quite mobile and have sufficient time
to repair dams or locate new overwintering sites.
Exceptionally, or continuously, high waters resulting from
diversion of drainage ditches into stream systems may not be
tolerated by beaver populations.
B(2) Stream Complexes: Sediment Load Alterations
This is undoubtedly a most significant relationship in
terms of both beaver and muskrat habitat, as the stream
systems are ultimately reponsible for carrying sediment
loads to all downstream aquatic environments. Some very fine
habitat has been, and is, perpetuated through annual
influxes of immeasurable sediment loads on the Mackenzie
Delta; it is difficult to envision significant alterations
of that regime. However, small headwater streams,
originating on gentle slcpes and carrying water through
small lake complexes, present an environment that is most
susceptible to the effects of siltation. Water depths within
this environment, so critical to overwintering pofulations,
can be seriously reduced by sediment deposition. Aquatic
plant communities can be retarded through decreased light
transmission accompanying turbid waters.
B(3) Stream Complexes: Introduction of Foreign Substances
Again, lubricating and fuel oil and toxic chemicals are
105
of particular significance, with streams serving as very
rapid dispersal agents. The effects of these pollutants on
aquatic furtearers are discussed under standing water
relationships.
B ( 4} Stream Complexes: changing Fire Regimes
Emphasis has been placed on the role that fire has
played in the past on beaver ecology within the study area.
On a protracted time basis, small local burns that favor the
seral stages of flant ~uccession can enhance available
beaver habitat, whereas burns that encompass whole
watersheds, leave streams clogged with debris and
susceptible to flash flooding and extensive erosion, will
completely destroy beaver habitat.
B (5} Stream Complexes: Removal of Riparian Cover
Streamside vegetative communities play simila~ roles
within the stream environment as within the standing water
environment, but their function in furthering bank stability
is greatly increased. Roots of nearly all plant species, and
the litter layer of decaying vegetation, serve to bind soil
particles against the erosive potential of high discharges.
Removal of riparian cover favors bank degradation (in itself
a loss of beaver habitat} increased silt loads and more
rapid runoff with associated downstream flooding.
C(1} Aquatic Furbearers: Audio-Visual Disturbance
Experience with highway rights-of-way and fipeline
operations in more southe~n regions indicates only limited
negative response on the part of individual muskrats or
beaver with rega~d to man's activity. There is some
possibility of a positive response as evidence by muskrats
building bank dens in levees or dykes, and beaver dams,
associated with culverts and dykes where stream flow is
confined.
C(2} Aquatic Furtearers: Increased Access Through Road
Construction
The current lucrative fur market dictates a strong
possibility of fur harvesting on local areas made more
accessible through highway completion. Indications f~om past
experiences are that beaver populations can be slow to
recover from local overharvesting. Muskrat populations,
showing a much more raFid turnover, seldom if ever suffer
from overharvesting. In many areas productivity is enhanced
by harvest programs. The economic importance of the fur
106
resource to local residents should not be overlooked in the
light of today's markets.
107
Table 7. Specific cause-effect relationships between pipeline construction
activities and aquatic furbearers.
Construction
Activity
Ditching
Berms, road
grades
Stream
crossing
Removal of
riparian
cover
Introduction
of pollutants
including fuels,
oils, toxic
chemicals
Direct Effect
Drainage of
standing waters
redirection of
runoff and
alteration of
normal flow
regimes
Increased runoff
Obstruction and/
or redirection of
normal surface
and sub-surface
flows
Introduction of
sediment loads
Introduction
of sediment
loads
Loss of bank
stability and
increased
sediment loads
Loss of food
supply
Increased
potential for
downstream
flooding
Direct mortality
within furbearer
populations
Destruction of
vegetative
connnunities
Aquatic Furbearer Habitat
Most Directly Affected
Small headwater lakes
within organic landscapes
Thermokarst lakes within
glacial lake basins
Small meandering streams
within low relief land-
forms
Small meandering streams
within low relief areas
Small headwater lakes
within organic landscapes
Deltaic lakes
Misfit streams within
glacial meltwater
channels
Deltaic lakes
All habitat
All habitat
Headwater streams
All habitat Potential
damage may be greater
within standing waters
that lack the "flushing"
action of stream systems
Species Affected
Beaver, muskrat
Muskrat, beaver
Beaver
Beaver
Beaver, muskrat
Muskrat, beaver
Beaver
Muskrat, beaver
Beaver, muskrat
Beaver
Beaver, muskrat
Table ]. Cont 1 d.
Construction Direct Effect
Activity
Operation Noise
of engine-
driven equipment
such as earth
movers, compressors,
etc.
Borrow pit
construction
Roads,
trails,
landing
strips
Degradation
of permafrost
regime, pot-
hole formation
Increased
access
Increased
frequency of
forest fires
Better forest
fire control
Aquatic Furbearer Habitat
Most Directly Affected
Minima 1 effect
Possible creation of
habitat
All habitat, parti-
cularly high density
wetland regions
Small headwater
streams, meandering
and convoluted mid-
drainage streams
108
Species Affected
Muskrat, beaver
Muskrat
Beaver, muskrat
109
5.7 WATERFOWL
5.7.1 Introduction
Very limited detailed information on the status of
northern waterfowl and their habitat was known or available
at the start of the study in late 1971. Therefore, study
proposals focused on a prcgram whereby, within the time span
of approximately 13 months (including the 4•month field
season of 1972), valuable information could be collected and
used to supplement known or interpretative information.
Further, it was intended such baseline information wculd set
the stage for any more specific investigations. The
objectives were:
1. Accumulate and compile availatle waterfowl data and
relevant knowledge.
2. Identify waterfowl breeding habitats within regional
landforms of the total Canadian Wildlife Service inventory
study area, using a 1:250,000 National Topographic Series
mapsheet basis.
3. Designate waterfowl habitat
characteristics, and formulate a
system.
"types" based on fhysical
meaningful class rating
4. Field check habitat types and record waterfowl species
(ducks, geese, swans; and secondarily, cranes and loons) and
presence of wetland vegetation.
5. Assimilate data, and on the basis of collective
information available, aEsign class ratings to known units;
apply extrapolation of facts, where necessary, to include
all delineated waterfowl breeding habitat units within the
study area.
6. Conduct aerial surveys of migrant waterfowl
concentration and Etaging areas.
one point must be made very clear: even as pure
inventory data, one year's observations leave much to be
desired. Climatic conditions vary, as do the numbers of
waterfowl which inhabit the north. Thus, the status of the
actual conditions and waterfowl productivity of northern
habitats is being assessed from what may in fact be a biased
sampling. Further, while an attempt was made to visit a high
percentage of habitat during the brief 4-month field season;
some areas could net be obEerved with the time constraint
110
and manpower available.
An assessment of the impact pipeline construction or a
transportation corridor would have on waterfowl and their
habitat was not planned for study in 1972. Consequently, the
predictions herein are based on available knowledge, and are
best described as an "educated guess" of conditions that may
prevail with proposed development.
5. 7. 2 Met hods
Basic Mapping Stage
Units vary in size to a minimum of less than 1 square
mile; and they identify lakes, wetland-upland complexes,
rivers, streams, bogs and fens. Wetlands which had similar
characteristics and which were in close proximity were
lumped into complex or combination units.
Mapping ~rocedures ~ere similar to those of the Canada
Land Inventory (Benson, 1965); with less emphasis placed on
contours, soils (information severely limited) and geologic
landforms.
Air Photo Interpretation
Source data were compiled prior to the field season by
a detailed evaluation cf defined waterfowl units using
stereoscopic air photo coverage. Physical similarities on
sample units were tabulated, noting: regularity and slope of
shorelines, wetland densities, aquatic vegetation (presence,
absence, distribution), upland vegetation adjacent to
wetlands; and islands, bars, oxbows, and flowages of lotic
(running-water) environments. Difficulties arose on occasion
as segments of aerial photography had been taken up to
several decades age and;or during periods of ice cover on
wetlands.
Class Bating System
The main objective of the waterfowl inventory has been
to provide a set of maps as a basis whereby the •relative•
importance of waterfowl breeding areas can be compared. The
basic 4-class rating system, that has been applied
universally to the Canadian Wildlife Service wildlife
inventory program, was inadequate for meaningful waterfowl
habitat evaluations because excellent and very poor
waterfowl breeding habitats were already known or easily
defineable. Therefore three "sub-classes" were inserted and,
l ll
consequently, ratings assigned to the present map series
are: Class 1 -excellent breeding habitat: Class 2a -very
good, Class 2b -good; Class 3a -fair, Class 3b -poor;
Class 4a -marginal, Class 4b -of insignificant or nil
value.
Accumulation of Available Information
Complementary to sources of information consulted for
the inventory and mentioned earlier, additional sources were
pursued. The u.s. Fish and Wildlife Service conducts an
annual aerial wateifowl species survey in the Western Arctic
to compile a rough index of breeding waterfowl populations.
As approximately 1600 miles of flightline laterally segment
the study area, unadjusted figures for 1970 and 1971 were
obtained and were useful as a check of unit ratings once
designated.
Field Investigations
Field checking of the waterfowl habitat units
delineated on preliminaiy maps began in late May and
extended to mid-August. A fixed-wing Cessna-185 airciaft was
used for low-level surveys of habitat; and, on occasion,
systematic population counts were made. Usually two
observers accompanied the pilot: one observed general
waterfowl species and numbers present, and the other noted
bio-physical characteristics of wetlands.
With the onset of spring breakup, aerial surveys began
in the southern region, and continued throughout the summer
on the entire inventory corridor. Flights were selectively
planned to intersect a maximum number of wetland units. Most
areas were visited once; and some several times.
Representative and unique wetlands, selected on the
basis of air phcto interpretation, were visited on the
ground. A Bell-206 helicopter was used to visit wetlands
where other aircraft could not land.
Collected information focused on measured water depths
of wetlands, species composition and abundance of aquatic
plants, physical and biotic characteristics of shorelines
and uplands, and species and approximate numbers of
waterfowl.
Assimilation of Data
As a consequence of many recurring
characteristics, the four main classes of waterfowl
physical
habitat
JJ2
have been considered in terms of the kinds of wetlands that
comprise them, with subsequent incorporation of information
on breeding waterfowl pairs and broods observed during
spring and summer surv~ys.
Decisions for final unit ratings on the illustrated
mapsheets were a result of consultation by at least two of
the three waterfowl habitat investigators.
Migration and Staging surveys
Aerial surveys from the cessna-185 aircraft were
generally flown at altitudes under 5CO feet above ground
level, and at speeds under 100 miles per hour. Routes were
planned and flown to coincide with spring breakup or, at
least, the first traces of meltwaters along the Mackenzie
River where migrant waterfowl were known to congregate. Two
separate return surveys along the corridor (from south to
north to south) were flown in the month of May. In addition,
localized counts were undertaken along the Mackenzie River
and on large lakes and rivers where concentrations were
suspected.
As breakup progressed, survey emphasis focused on
assessing waterfowl breeding habitat. During July and
August, breeding pair and brood production surveys
encompassed the entire study area.
Migrant waterfowl using the Mackenzie River as a flyway
route were monitored at Fort Simpson during late August and
September. This undertaking was part of a concerted effort
involving personnel from government and private wildlife
investigation groups to study the fall migration of
waterfowl from the western Arctic. Due to delays in computer
processing, study results are not available as of April
1973.
5.7.3 Results and Discussion
Illustrated waterfowl Habitat
A mapsheet series which consists of reduced copies of
1:250,000 National Topographic Series mapsheets depicting
present waterfowl habitat values for the study area is
contained within a booklet titled 'Atlas of Waterfowl
Habitat Maps'.* The most significant information to be
conveyed is the £Ql~1iYQ importance of areas to one another,
consideration bein9 given to physical features and the
densities of waterfowl species inhabiting individual areas.
*See note in Table of Contents
113
It is important to point out here that northern
waterfowl habitats produce fewer ducks than prairie wetlands
on a per-acre basis; however, a number of waterfowl species
depend on northern habitat for their very existence and the
maintenance of present continental populations. Portions of
the Arctic Tundra Biome are heavily utilized by major
populations of geese and swans.
Wetland Descriptions
Wetland descriptions are provided in the Atlas to
ensure that the reader gains an appreciation of
characteristic aquatic environments which comprise the
habitat for both waterfowl (including large water birds such
as cranes and loons) and aquatic furbearers (beaver and
muskra~. Further, they help to convey an understanding of
delineated habitat units on the illustrated waterfowl maps.
5.7.4 Implications and Recommendations
Efforts to date have been oriented toward an inventory
of waterfowl and waterfowl habitat within a vast study area,
which includes all probably transportation routes Because of
time limitations, it was not possible to undertake specific
"impact" studies which would yield information concerning
the effects of development activities on wetlands habitat or
waterfowl species.
Basically, an impact study requires two separate sets
of data before such a study can be undertaken. These are:
(a) the sensitive components of given ecosystems, and (b)
the actions which are expected to cause the impact. In the
case of arctic waterfowl, the sensitive factors in habitat,
behavior and population dynamics, are little known; and the
expected actions are unknown to us either in magnitude or in
exact geographic location.
With the information which is at our disposal now, it
is possible only to speculate on the possible effect of
pipeline construction in the study area, using inventory
data, experience of habitat management, behavior of
waterfowl, information on bird migrations, and whatever
information en pipeline construction that is available.
Discussion pertains to general speculations only.
Detailed speculations or forecasts would require mile by
mile investigations when the exact pipeline location and
114
construction methods are known. In othe~ words, the purpose
of this section is to assess the general effects of pipeline
construction on waterfowl and waterfowl habitat.
The following are factors of concern should
construction plans materialize for any gas or oil line, or
highway.
1. Loss and degradation of waterfowl habitat.
2. Disturbance of waterfcwl.
3. Excessive harvests of the waterfowl resource.
Loss and Degradation of Habitat
Loss of habitat will be caused by complete or partial
drainage, drowning, or filling in with solid materials.
Degradation of habitat can be caused by changing water
levels, permanently or duiing certain periods; siltation;
wildfires in the ecotone surrounding the habitat; or
pollution of the water with foreign materials.
It is assumed that construction of a buried pipeline
will use a six or seven-foot deep trench, which will be dug
as straight and as level as terrain conditions permit. The
effect of such a trench on water levels or nearby wetlands
is not known. A fu~ther assumption is that such a pipeline
will te buried in the bottom of shallow lakes, pcnds and
marshes; but that it will gc around deep lakes.
A buried pipeline going through a shallow lake or marsh
should have little lasting effect on the habitat quality
if the thermo-regime of the water near the pipe is not
altered due to the heat less of a hot oil pipeline, or the
chilling effect of a chilled gasline. Insulation will reduce
the rate of heat flow and effects are expected to be local
and not generally degrading to the habitat. Gradient
approaches of pipeline crossing lakes and marshes shculd, of
necessity, be guickly restored to simulate natural
conditions, thereby minimizing drainage alteration.
Where the submerged pipeline crosses a stream it is
vital to restore the natural profile of the stream in order
to avoid stream diversions and water-level changes in the
watershed which could cause drainage or drowning of marshes.
At stream crossings it is important to avoid the ercsion of
fill which could cause silting of marsh areas and the
included aquatic vegetation.
115
Fires should be avoided, especially near wetlands.
Although the vegetation of the edge of wetlands may seem
unimportant to waterfowl, these sedges, grasses, ericaceous
shrubs and willows provide vital nesting and escape habitat.
It is expected that indirect degradation of wetland edges
through exposure of permafrost, and consequent slumping of
banks will occur, but it is not known that such slumping
will continue or that the same plant communities will return
and stabilize the bank or wetland's edge. Further, it is
expected that the regeneration of the desirable plant
species would be slow, and therefore the habitat would
degrade in quality for several years to come. If a fire
would occur in such habitat during the nesting season,
nesting waterfowl would lose their clutches of eggs without
an opportunity to re-nest successfully. One can expect more
numerous man-caused wildfires with the proposed development;
however, improved surveillance and access may facilitate
better control of naturally-occurring wildfires.
It is of the greatest importance that gasoline, diesel
fuel, other petroleum products, and toxic chemicals should
be stored in such a place that, in case of a leak, such
fluids do not flow into a drainage system. These fluids
would cause disastrous effects on waterfowl; and even if the
spills occurred in the absence of waterfowl, long lasting
remnants of them could cause serious mortality during later
use of affected wetlands by waterfowl. It is assumed that an
oil-line will be designed to be leakproof, but the
disastrous lasting effects of oil in waterfowl habitat
cannot be over-emphasized.
In the spring, the islands in the Mackenzie River serve
as resting areas for large numbers of migrating geese and
swans. At the peak of migration more than 100,000 birds may
concentrate on favorable resting areas such as sandy bars
and island fringes. It is expected that the removal of sand
and gravel from these areas will change the ecosystem and
would make these areas unsuitable as resting and feeding
sites. For instance, it may be expected that the removal of
sand and gravel will change the profile of the shoals which
in turn will have a detrimental effect on the aquatic
vegetation and invertebrate organisms, both of which may be
used as food for waterfowl. Also, removal of sand bars and
spits may result in exposure to wind and wave action of
formerly sheltered resting areas. To sum up, it is expected
that removal of sand and gravel from sand bars and island
fringes will result in degradation of migration habitat,
which could seriously affect migrant geese and swans.
outlets of tributaries to the Mackenzie River are,
I 16
following break-uf, freguented by large concentrations of
waterfowl such as scaup, oldsguaw, seaters, and loons. These
migrants use these water areas because they provide open
waters early, and likely have a richer food supply than the
main river. It is expected that any restriction of stream
flow upstream from such outlets will result in degradation
of these resting and feeding habitats.
The coastal zone of the Beaufort Sea, which consists of
large bays such as Shallow, Kugmallit and Liverpool bays, is
especially important to arctic waterfowl. The shallow waters
along the ocean foreshore, especially those protected from
the open sea by barrier beaches, provide moulting and
staging areas for an important part of the continental
waterfowl population. For instance, from mid-August until
freeze•up (mid-September) practically the entire continental
population of lesser snow geese utilize the coastal zone
usually along the North Slope of the Yukon. Geese, Brant,
swans, and ducks (including sea ducks) may total 300,000 and
more birds in this area.
It is expected that physical changes to the coastal
zone, e.g. through remcval of sand and gravel, or a
transportation system using causeways to connect sand bars,
would be detrimental tc this type of habitat because a
change in currents and a resultant reduction in the
production of biomass of aquatic food species are distinct
possibilities.
In this type of habitat, where bio-degradation is slow,
the spectre of oil pollution looms large. Even in the case
where oil wculd not be transported by pipe through this
area, the danger of pollution of this fragile habitat by oil
used by shipping or land-based activities is a constant
threat.
A short summary
habitat which may be
presented in Table 8.
Disturbance of Waterfowl
of expected
incurred by
effects upon waterfowl
major development is
waterfowl are sensitive to disturbance by man and
machinery. Reactions to disturbance vary among species of
ducks, geese, and swans, but the first reaction to a
possible threat is flight. Because waterfowl are extremely
mobile, disturbance and harassment (including excessive
noise and irresponsible shooting) can cause them to desert
favorable resting, feeding or nesting habitat and thus
117
lessen the chance of survival of the species.
The waterfowl Atlas Ehows critical waterfowl migration
habitat. Part of the Mackenzie River complex of islands,
outlets of tributaries, and marshes adjacent to the River
make up a portion cf this critical habitat. Large numbers of
migrants, such as 100,000 geese and tens of thousands of
scaup, seaters, cldsquaw and other species, use the
Mackenzie River and its associated wetlands when the first
sign of break-up aFpears; and move northward with ice break-
up and rising waters. This migration period spans all of May
and sometime extends into June, depending on seasonal
variations. These species are very intolerant to disturbance
and it is expected that human activity within close
proximity of such areas will harass the birds. Furthermore,
it is expected that the effects of blasting as far as
several miles away may cause the birds to leave preferred
habitat. overflights of low-flying aircraft can be expected
to disturb birds beyond the threshold of tolerance; large
helicopters in particular should avoid over-flights of
critical waterfowl areas.
Nesting waterfowl are extremely intolerant to
disturbance. An extended period of such disturbance may
cause the incubating bird to desert the clutch altogether,
or to leave the nest, subjecting the eggs to low
temperatures and to attacks by avian and terrestrial
predators.
It is expected that disturbance by man and/or aircraft
of breeding swans and geese during the period from May 20 to
July 1 will cause a seriouE less of production.
In early August, waterfowl begin to concentrate along
the coastal zone until the total populations have built up
to 300,000 or more birds. Geese feed on sedges and berries
on the upland slopes and, in doing so, condition themselves
for the long flight southward.
It is expected that disturbance by man or by aircraft
of waterfowl on the staging areas and feeding grounds from
approximately AuguEt 10 to freeze-up will cause unnatural
mortality due to displacement of birds from their critical
traditional feeding, loafing and resting areas.
Results from a study on the outer Mackenzie Delta, near
the Kendall Island Migratory Bird Sanctuary, by Barry and
Spencer (1972) indicated that overall waterfowl production
declined and populations of snow geese were markedly reduced
in proximity (1 1/2 miles) to an area of major activity (a
118
drill rig site). Also, in July, family groups or flocks of
flightless moulting birds moved to a distance of several
miles distant, avoiding the habitat they had used in past. A
most important inference resulting from that study is that
any development camps, settlements, and major supply routes,
should be located at least 3 miles distant from critical
waterfowl areas.
A short summary of expected disturbances to waterfowl
which may be incurred by major construction activities is
presented in Table 9.
Excessive Harvest of the Waterfowl Resource
It may be expected that construction activities and the
presence of the piFeline with its facilities for access will
increase the present low waterfowl harvest through hunting.
During the construction stage, if regulations concerning the
restriction of firearms are observed, a slight increase in
harvest other than by natives can be expected. However, as
areas become more accessible, adventurous "outsiders" will
take advantage of the large concentrations of waterfowl,
particularly in the coastal areas where one presently would
have the opportunity to kill several hundred geese per day.
In order to prevent excessive kills, strict enforcement of
regulations and inspection of hunting camps would be
required.
119
Table 8. A summary of expected effects upon waterfowl habitat which a pipeline or
highway construction may produce.
Cause
Trenching in wetlands
without proper grade
Creation of berms, road
base
Construction of borrow
pits
Heat loss or chilling
incurred by buried pipe
Stream crossing of
pipe 1 i ne
Stream crossing of
pipe 1 i ne
Wi 1 d fires
Pollution by oil,
petroleum products, or
other toxic chemicals
Removal of sand and
gravel from river
islands, bars, etc.
Diversion of tributaries
to Mackenzie River
Removal of sand and
gravel from coastal
formations or change of
such formations
Waterfowl
Expected Effects
Loss and Degradation of Habitat
Possible Effects
Change of drainage; redirection
of runoff; channelling of surface
and sub-surface drainage
Disturbance of runoff and
normal drainage
Habitat creation
Change of thermo-regime
Drainage or drowning
Erosion of fill;
sedimentation and filling
in of basins; succession
of vegetation species
Loss of nesting and escape
habitat
Serious degradation of habitat,
damage lasting for years
(direct marta 1 i ty to
1 oca 1 b i rd s)
Serious degradation of habitat
possibly lasting
Serious lasting degradation
of habitat
Serious lasting degradation
of habitat
Magnitude
Small-large depending
on topography
Small-moderate
Moderate (favorable)
consult Biologist
Small-moderate
Sma 11-moderate
Small-moderate
Moderate
Large
Moderate
Moderate
Large
Table 8. Cont 1 d.
Cause
Oil or toxic chemical
pollution of coastal
waters
Possible Effects
Serious lasting degradation
of habitat (direct mortality
to local birds)
120
Magnitude
Large-disastrous
Table 9. A short summary of expected disturbances to waterfowl which
may be incurred during pipeline or highway construction.
Waterfowl
Expected Effects
II Disturbance
121
Cause Possible Effect Magnitude
Construction, and
particularly blasting
within two miles of
designated areas of
Mackenzie River May 1 -
June 15
Overflight of aircraft
less than 2,000 feet
altitude over designated
areas May 10 -July 1
Disturbance by man or
aircraft of designated
waterfowl breeding areas
May 20 -July 1
Disturbance by man or
aircraft of designated
staging areas August 10 -
September 21
Disruption of migration
pattern
Disruption of migration
pattern
Serious disruption of
breeding and abnormal
mortality
Serious disruption of staging,
possible premature migration;
abnormal mortality
Large
Large
Large
Large
122
5.8 RARE AND ENDANGERED SPECIES -RAPTORS
The raptors referred to in this section are the
peregrine falcon, gyrfalcon, osprey, bald eagle and golden
eagle. Although all five species are not equally as rare or
endangered, they may all be influenced by the construction
of a pipeline. In crder tc protect the more valuable and
more eagerly sought after species, they will all be
discussed as a group of birds of prey and referred tc under
the one general heading, raptors.
Many sightings and eyrie locations were made during the
1972 surveys, and many more were gathered from other
Canadian Wildlife Service, consortia, and interested
industrial personnel. To Frotect the remaining known nesting
sites of endangered species, such as the peregrine falcon,
the locations of these will be kept strictly confidential
within the Canadian Wildlife Service. Pertinent information
will only be released to an agency which has jurisdiction
over future land use if it is felt that the release is
necessary to protect the species or location involved.
The reason fer this restriction on information release
is obvious. Peregrine falcons and gyrfalcons are fervently
sought after for use as hunting birds. These birds bring a
handsome price, sometimes as much as $3,000 to $5,000. As
they become more rare, they become .more valuable, and more
sought after. Some provinces and states have put tight
restrictions on the keeping of wild animals in captivity but
many have not. Foreign countries also present a considerable
demand. Since raFters traditionally use the same nesting
territories year after year, any public release of exact
locations would immediately place that nest in jeopardy
through disturbance by curious tourists, photographers, egg
collectors or falccners.
The following report was prepared with the above in
mind. Only those locations where direct conflicts are
expected have been noted and they have been referred to as
raptor nests. Any change in route location shculd be
accompanied by a re-examination of the raptor information
for additional conflicts.
The construction phase of the proposed pipeline should
not seriously affect raFters in general; however, it will
contribute to the ever-increasing reduction of their
numbers. For every 28 to 30 miles of pipeline, 1 square mile
of land will be directly 'lest• through construction
activities. Whether this will include raptor nesting habitat
will depend on its location. Since raptors are wilderness
123
species, the area actually affected may be much greater than
that directly affected by the pipeline construction. Nesting
sites as far away as two or three miles on each side of any
construction activity, including camps, airports, haul
roads, blasting, etc., may be influenced. All nest sites
along the proposed route have not been located, so the
actual number of raptors that will be involved is not known.
Although the disturbance due to construction will
likely be temporary, the effects may be permanent. At least
two of the raptor species, the peregrine falcon and the bald
eagle, are known tc be declining in numbers. Once displaced
from traditional nesting sites there is no assurance that
they will return.
The anticipated increased human pressures will also
extend the area that will be affected. The effect cf human
presence and activities en raFtors varies with season.
Disturbance during the establishment of territories in early
April or May may lead to desertion of the site. Later
disturbances of very short duration, even for an hour,
during the egg-laying and incubation period (May to June}
may lead to loss of the eggs and young. Disturbance during
the flightless period of the young from June to August may
lead to abandonment or increased predation of the young.
The threat of illegal egg collecting, irresfonsible
shooting of young and adult raptors, and the robbing of
young from nests for falconry will accompany any increased
human access and activity associated with the construction
and operation of the pipeline. This problem is inevitable
and can only be partially controlled by limiting access and
increased publicity and enforcement of game regulaticns.
The increased introduction of pollutants and chemicals
into the northern envircnment could seriously affect these
birds. Already detectable amounts of many pesticides are
being found in the northern ecosystem. Falcons and eagles
are known to be seriously affected by some of these
chemicals. Any use of pesticides and herbicides should occur
only after consultation with Canadian Wildlife Service
biologists.
Since all but the bald eagle and osprey are
traditionally cliff nesters, the areas of potential nest
sites can be narrcwed ccnsiderably. Known and potential
sites can be found throughout the Yukon and the mountainous
regions of the western Northwest Territories.
Along the proposed pipeline routes the major areas of
124
concern are the Franklin Mountains, some areas along the
banks of the Mackenzie, the Richardson Mountains, the
British Mountains, and the Porcupine River. Many of the
major and minor rivers draining the mountainous regions flow
through deeply eroded valleys. The exposed rock faces
provide excellent nesting sites. Many still remain to be
investigated.
The osprey and bald eagle nests are generally found in
forested lowland areas in close association with lakes and
ponds. Peregrine falcons are usually restricted to cliffs in
forested areas quite often overlooking water. The gyrfalcon
prefers the more open cliffs above treeline. Golden eagles
are more widespread, although they too prefer the ~ountain
cliffs. Golden eagles are particularly abundant in the
British Mountains where the Porcupine caribou herd fcrms an
abundant food supply.
There are only two known areas where the presently
proposed pipeline route will result in direct raptor
pipeline conflicts.
There are several raptor nest sites across and
downstream from Arctic Red River on the steep banks of the
Mackenzie River. These have been present and active for some
time. Already development has caused the destruction and
abandonment of several, and there is some doubt as to the
possibility of saving the remaining few. If the pipeline is
to cross the Mackenzie River at this point, every effort
should be made to use the same approaches to the river as
were constructed fer the Dempster Highway. This will help
keep the destruction of nesting sites at a minimum. Blasting
and other construction activity should be completely
restricted during the nesting season from April to August
for at least 2 miles on either side of the cliff area.
This river valley is known for the raptor nests located
along it (de Belle, et al. 1972). The presently proposed
pipeline route will destrcy or severely disturb at least two
nest sites located near the mouth of the Driftwood River.
The route should be kept at least 1 mile from the river at
these spots to avoid nest destruction, and construction
should not take place during the nesting season which is
from April to August.
There are alsc at least seven additional kncwn and
125
potential nesting areas ~here disturbances associated with
pipeline construction and activity should be restricted
during the nesting season. These are:
1. The sections of the route that pass particularly
close to the exposed rock cliffs of the McConnell Bange and
the Norman Bange;
2. The Mackenzie River banks at the Ramparts and Fort
Good Hope;
3. The exposed rock cliffs around Campbell Lake south
of Inuvik;
4. The McDougall Pass area;
5. The Porcufine River;
6. The Old Crow River; and
7. The exposed rock cliffs of the Old Crow Bange.
There are several other likely nesting areas along the
route, but most are located outside the 2-mile limit of
major disturbance. These are being thoroughly investigated
during 1973. Any suggested re-routing of the pipeline should
take these locations into account. Concern is also expressed
over selection of campsites, air strips and haul roads; each
of these could easily have as serious an impact as the route
itself. The exposed cliffs favored as nest sites by raptors
may be sought as scurces of gravel and rock. The positioning
of comfressor stations may cause disturbance, if not through
noise then through associated human activities. Provisions
should be established so that before decisions on the
locations of any development are made, raptor information
should be obtained and reviewed. Raptors are very sensitive
to disturbance and have the potential of becoming the
wildlife species most seriously affected by northern
development. Careful selection of route and associated
development location can keep the influence of pipeline
construction at a minimum.
5.9 RARE AND ENDANGERED SPECIES -POLAR BEARS
5.9.1 Introduction
The area under discussion extends along the coast of
126
the Beaufort Sea from the west of Herschel Island, Y.T. to
about Baillie Island, N.W.T.
In any conflict between exploration or development and
bears there are several types of potential problems. In
planning for such development activities, the interests of
both the bears and the activity should be considered.
5.9.2 Discussion
Polar Bear Denning Areas
Apparently little maternal denning of polar bears
occurs on the mainland ccast or associated offshore islands
of the Yukon and western N.W.T. The only sites known to have
been u~d within living memory are Herschel Is1and, Y.T.,
Pullen Island, N.W.T., and Nuvorak Point, N.W.T. Thus, there
is probably little potential for damage to the species
through interference with denning areas. Nevertheless, some
vigilance and care should still be recommended when
operating near drifted banks or streambeds near the sea,
points of land, or offshore islands.
Polar Bear Feeding Areas
During the reriod of open water along the mainland
coast, the occurrence of polar bears on land is rare.
However, in the fall when the polar pack ice moves south and
the newly formed sea ice joins the pack to the mainland, the
bears move south and are abundant near the coast. All
through the winter and spring until breakup, there are
working leads in the sea ice that run in an east-west
direction parallel to the coast. This is where the seal
hunting is best and, consequently, is also the area in which
polar bears concentrate. The points of land where these
leads occur closest to shore are Herschel Island and Baillie
Island. Because these two islands are offshore of natural
headlands, it is likely that the effect of coastal currents
and ice movements en the maintenance of broken ice areas is
greatest there. Folar tears tend to concentrate near both
these islands during winter.
Excessive activity by men and machines could alter the
movements of these tears, resulting in a shift of
distribution away from these points. The effect on the bears
of such a shift might not be too serious because they could
likely obtain seals elsewhere, although possibly under less
favorable hunting circumstances. However, Eskimos that
depend on hunting polar bears (as well as trapping white
127
foxes) at Herschel and Baillie islands for part of their
livelihood, could te seriously affected.
In 1970 and 1971 at Herschel Island, large numbers of
bears were reported near the settlement in late October and
early November. In the fall of 1972, there was excessive
aircraft movement, land vehicle activity, and construction
of an airstrip. Several fuel storage tanks and a baige were
also positioned duiing the summer of 1972. Few polar bears
were seen. Observations over sea ice between Banks Island
and the Alaska bordei in late october and early November
revealed many tracks and 22 bears. Thus, bears weie again
abundant in the area, yet scarce at Herschel Island where
the noise of mechanical activity may be responsible for
their absence.
5.9.3 Implications
It is expected that -
a. The excessive noise of vehicular activity, from late
fall to early spring, is likely to be disruptive to coastal
wildlife movements; in particular to polar beais, and
possibly to white foxes as well.
b. Fuel storage tanks right by the edge of the sea raise
the threat of an oil spill which could cause great damage to
the marine eccsystem upcn which the seals, polar bears, and
beluga whales depend. This threat is intolerable.
5.9.4 Recommendations
To date, no effective chemical tear repellent is known.
The best defence for any camps is absolute cleanliness, and
this cannot be over-emphasized. Garbage should be
incinerated and tack-hauled. Materials such as frozen meat
should be kept enclosed. Sewage should be containerized and
back-hauled or incinerated.
Even with the best of precautions some bears will
approach a camp or even a vehicle out of curiosity. camps
should be equipped with some of, or all of, the following
scaring devices for use as deterrents:
1. Thunderflash, CIA! (Thrown by hand)
Dept. of National Defence
Ammunition Group
Base Supply Section
Canadian Forces Base
Shilo, Manitoba
2. Teleshot, 12 gauge (Bird control cartridge;
shot from standard 12 gauge shotgun}
colt Industries
colt Firearms Division
u.s.A.
3. Twinshots (same as no. 2}
Maison D' Armes
181 Rue ste. Paul
Que bee, P. Q.
4. Bird Bombs
w. v. Clow Seed Co.
1107 Abbott Street
Salina~, California 93901
u.s.A.
Also available from Ketchum Mfg.
sales Ltd.,
396 Berkeley Ave.
Ottawa 13, Ontario
128
129
6. GENERAL DISCUSSION
The relationships between the studies described in this
report and other studies presently undertaken, such as the
Mackenzie Valley Highway Study, and those contemplated of
the Arctic Islands, are obvious, but at the same time not
clear in detail. In order to explore these relationships, it
is necessary to investigate at least three separate areas:
those of design, aralysis and extrapolation of results.
!he gesig~ to present information in the form of an
inventory map series, is applicable to almost any land-use
planning task. Similar designs were used by the Canada Land
Inventory, the original "Arctic Ecology" map series, and
very recently the ALUR Land-use information map series. An
inventory map series shewing wildlife habitat units can be
used to identify important habitat in the vicinity or in the
path of the pipeline or highway. Maps of the scale of
1:250,000 are useful for general planning purposes. However,
for detailed assessments of river crossings, and marsh
crossings they do not provide enough detail. our experience,
so far, has been that detailed engineering designs are not
available at the right moment, and once they are available
there is not sufficient time to study their exact location,
let alone to study their effects on the environment. For
instance, it is not possible to assess the effects of a 20
to 30 mile stretch of highway in one week, never having seen
the terrain on the ground in detail nor the habitat or the
animals involved.
Until the proposed locations of pipeline routes are
finalized, there seems little point in doing detailed
habitat investigations alcng routes currently shown on maps
or photo mosaics prepared by the gas pipeline study
consortium. Further wildlife-pipeline investigations will be
limited by the amount of advance information available on
proposed engineering methods and by the relative lack of
precise details cf proposed locations for construction
camps, access roads, storage areas and all other activities
associated with construction of a large-diameter pipeline.
Once such details are known, much more specific wildlife
investigations can be undertaken, providing there is time to
do so. Detailed habitat investigations would require at
least one field season, and with selections of sites on air
photos and final preparation on maps, will take a full year
from the date that detailed design perhaps would become
available.
The an~!Y£!§ cf inf2£mation obtained from the present
wildlife habitat inventory is simple in one aspect -the
130
delineation of important wildlife areas; it presents great
difficulties in ethers, such as the "social" evaluation of
habitat values and the estimation of "impact".
The maps which are part of this report show wildlife
units in classes of quality, and at a glance their position
relative to a proposed construction location can be found.
Consequently, areas of possible conflict can be easily
identified.
The estimation of ''impact" can only be general, because
the engineering techniques are not known to us and the exact
location of the structures: highway -pipeline -camFsites -
bridges underwater crossings, are not known either.
Therefore, the speculations on effects of construction have
to be of a very general nature.
The evaluation of habitat units and the wildlife they
support from a social point of view is outside the scope of
this report. The relative importance of one wildlife species
compared with that of another is a hazy subject. Are
mallards more ''important" than shorebirds? Are grizzly bears
more "important" than moose?
The ~!!~EQ1atioQ £1 ~]l!§L for use in similar
studies, is possible to a limited degree. For instance,
behavior of a certain species of waterfowl subjected to
disturbance might be expected to be the same on the Arctic
Islands as on the coastal zone of the Beaufort Sea. In
general, species which occur in the present study area are
expected to have the same sensitivity to disturbance and
habitat degradation as the same species of wildlife which
inhabit the Arctic Islands. Due to different terrain,
habitat units are expected to be different from these of the
present study area.
131
7. GENERAL CONCLUSIONS
The purpose of this chapter is to summarize the main
conclusions and assemble this information for all species in
one chapter.
7. 1 Moose
Moose are widespread throughout the Mackenzie River
Valley and northern Yukon. While in summer their movements
are almost unrestricted, in winter they confine themselves
to three main habitat types which are river valleys, wetland
complexes and upland slopes.
Moose wintering in river valleys are vulnerable to
disturbance or hunting because the topography and possibly
snow depth could hamper their escape movements and the
animals are concentrated in large numbers. Moose are very
dependent on natural habitat disturbance for their
existence. Flooding of the floodplains of fast-flowing
mountain rivers and wild fires create most of the hatitat in
the upstream reaches of the Mackenzie River, while in the
north the shallow active layers over the peimafrost
restricts the growth of browse species to the river
channels.
7.2 Caribou
7.2.1 Caribou, other than the Porcupine herd
There are two, or probably three sub-species of caribou
in the Mackenzie Valley; woodland caribou, barren-ground
caribou, and reindeer (originally escaped from the Eeindeer
Project). The woodland caribou are common throughout the
study area from the Alberta border to south of Inuvik along
both sides of the Mackenzie River, while most of the barren-
ground caribou belong to the Bluenose herd, which has been
estimated to consist of 20,000 to 150,000 animals. The
escaped reindeer or offspring of escaped reindeer may
possibly contribute to a group that ranges between the
Eskimo Lakes in summer and the Travaillant Lake-Iroquois
rivers area in winter.
Woodland caribou west of the Mackenzie River are
restricted to the Mackenzie Mountains and the adjacent
foothills and lowlands; large groups were observed along the
headwaters of the Keele, Redstone, Carcajou and Arctic Red
132
rivers. Woodland caribou east of the Mackenzie River are
seldom concentrated, but radiate out from their summer
ranges into suitable winter habitat.
Groups belonging to the Bluenose herd of barren-ground
caribou may winter as far south as the Horn Plateau, and
some animals spend at least part of the winter along the
Willow Lake, Blackwater and Great Bear rivers.
The group that ~eems to summer just south of the Eskimo
Lakes and winter in the Travaillant Lake area numbers about
1,000 to 2,000 animals and does not concentrate but stays in
small groups of 2 to 20.
7.2.2 The Porcupine herd of Barren-Ground caribou
Data collected by various agencies suggest that
variations, both chronological and spatial, exist in the
yearly cycle of the mig~atory barren-ground caribou.
Variations may be either short-term or long-term, where it
is assumed that a short-term variation does not last more
than five years. Chronology of spring movements during 1971
and 1972 for the various migration paths show variations of
a week for the Old crow Route and up to six weeks for the
Richardson Route. It may be concluded then that within a
short time span up to several years, movement chronology can
vary by months and movement may or may not occur. over long
periods of time measured in human generations, it would
appear that caribou movements are relatively dependable.
7.3 Dall Sheep
All important Dall sheep habitat is situated west of
the Mackenzie River. Winter habitat consists of four major
types: plateaus and gentle slopes; slopes and lateral spurs
at treeline slopes; spurs associated with eroded bluffs; and
high ridges and slopes.
Four major tall sheep populations are known in the
study area; the Nahanni, Ram, Yohin-Liard group; the
Mackenzie Mountains group, the Richardson Mountains group
and the British Mountain~ group.
7.4 Grizzly Bears
surveys were conducted in the early spring when the
bears are first emerging from their winter dens. It proved
133
very difficult to retrace tracks to the den site, unless the
bear had just recently emerged. From the observations it
seems that grizzly bears depend more on availability of food
than on specific habitat types. Adult male bears have a very
large home range, while females with cubs travel in a small
radius from their den. Although availability of food and not
habitat seems to influence the presence of bears, large
habitat units can be identified.
There is a definite preference by grizzly bears for the
rough, broken terrain of the mountains and hilly regions
over the flat densely forested areas of the south and
central portion of the study area. Grizzly bear sightings
were most numerous in the mountain regions of the northern
Yukon. The Yukon coastal plain, Richards Island and the
Tuktoyaktuk Peninsula support good bear populations.
7. 5 Arctic Fox
Delineation of habitat types for arctic fox is
difficult due to the cyclic nature of the animal. Habitat
quality was determined by several factors, of which the
relative density of maternal dens was one. The greatest
concentration of arctic fcx dens was found in the Herschel
Island mapsheet area. Dens were found on sand dunes, frost
heaves, and on banks of watercourses and lakes, usually in
porous soil materials.
7.6 Beaver and Muskrat
Within the study area, beaver and muskrat can generally
be found wherever the basic habitat requirements, including
suitable food and shelter, are available. However, it is
possible to indicate some areas which are of special
importance.
The most extensive areas of better quality beaver and
muskrat habitat cccur in the deltaic complex of the lower
Mackenzie River and the thermokarst lakes within glacial
lacustrine basins along the Ramparts River west of Fort Good
Hope, the Brackett River northeast of Fort Norman, MacKay
Creek south of Fort Norman, and west of the Mackenzie River
at Camsell Bend.
Lakes of the Old Crow Flats and several less extensive
basins along the Porcupine River provide very favorable
muskrat habitat but are of only minor importance to teaver.
134
Drumlinized till deposits, between Fort McPherson and
Martin House, provide a combination of drainage confinement
and shoreline stability that beaver prefer for dam
construction.
In the more scuthern regions, good beaver habitat is
found within stream systems on the gently sloping flanks of
several large plateaus. Very extensive organic overburden in
the headwaters and excellent deciduous shrub cover along the
meandering mainstem channels contribute to the overall value
of these systems. Harris Creek north of Fort Simpson, the
south fork of the Martin River and the Matou River near
Sibbeston Lake, and the unnamed stream emptying into the
northwest side of Trout Lake, all fall within the above
category.
Two other areas of good quality beaver habitat worthy
of mention are the Tetcela River, occupying a broad u-shaped
intermontane basin on the west side of the Sibbeston Lake
mapsheet and the deltaic region on the lower Kakisa River.
7.7 Waterfowl
Waterfowl use the study area annually from May until
September.
The Mackenzie River, its islands and mouths of
tributaries, is a major migration pathway along which many
thousands of waterfowl travel, rest, wait for open water and
gradually move northward during spring. The Boieal and
Tundra regions provide thcusands of lakes, ponds and streams
suitable as nes(ing habitat, while later on in midsummer,
the coastal waters and laige inland lakes are used by flocks
of moulting adult birds. In early fall, several hundred
thousand birds concentrate on the North Slope and estuarine
areas of the Mackenzie Delta where they condition themselves
for their southwaid migration.
The waterfowl involved are geese, ducks and swans; some
reference is made to loons. The inventory has identified the
following extensive areas of good waterfowl breeding
habitat: the Old Crow Flats, the Mackenzie Delta, the
Tuktoyaktuk Peninsula and adjacent lowlands, the Bamparts
Flats, the Brackett Lakes and the wetlands adjacent to the
Kakisa River. Less extensive areas, such as basins situated
in alluvial sediments on floodplains and deltas, provide
habitat of equal importance.
135
7.8 Faptors
The falcons, osprey and eagles are discussed as one
group of birds of Frey. All but the bald eagle and osprey
are traditionally cliff nesters, therefore the areas of
potential ne~t sites can be narrowed down. Known and
potential sites can be found through the Yukon and the
mountains of the western Northwest Territories, such as the
Franklin Mountains, the Richardson Mountains, and the
British Mountains. Some sites also exist along the eroded
banks of the Mackenzie and Porcupine rivers as well as along
the deeply eroded valleys of many of the major and minor
rivers draining mountainous regions.
It was found that the osprey and bald eagle generally
nest in forested lowlands close to lakes and ponds.
Peregrine falcons are usually found on cliffs in forested
areas, while gyrfalcons prefer open cliffs above treeline.
Golden eagles are abundant in the British Mountains.
7. 9 Polar Bears
The only maternal denning sites known to have been used
by polar bears in the study area are on Herschel Island,
Y.T., Pullen Island, N.W.T., and Nuvorak Point, N.W.T.
During the period of open water along the mainland
coast the occurrence of polar bears on land is rare.
However, in the fall, when the polar pack ice moves south
and the newly formed sea ice joins the pack to the mainland,
the bears move south and are abundant near the coa~t. All
through the winter and spring until breakup, there are
working leads in the sea ice that run in an east-west
direction parallel to the coast. This is where the seal
hunting is best and, consequently, is also the area in which
polar bears concentrate.
136
8. IMPLICATIONS AND RECOMMENDATIONS
The relationships between wildlife populations and
habitat and the construction of an underground gas Fipeline
are at best vague. Lacking specific and detailed information
on location, design, and techniques of construction,
speculations on imFact become necessarily very general.
An attempt to bring the various impact speculations
presented in the individual "chapters" together is given in
Appendix III. In most cases a pessimistic view has been
taken of the magnitude and duration, indicating what may
happen under the worst situations. Realistically, most
construction activities will have a wide variety of effects,
and many may be beneficial under certain circumstances. For
example, the creation of water bodies through obstruction of
drainage or borrcw pit excavation can, through proper
management, create satisfactory waterfowl and muskrat
habitat. Sedimentation has in many places enhanced lakes and
estuaries, creating deltas and delta-like situations
extensively used as waterfowl and muskrat habitat. Wildfires
over the long-term are beneficial to moose and in fact may
be the major reason fer widespread occurrence of this
species in the North.
The table in Appendix III does not reveal FOssible
remedial measures that may alleviate construction impacts.
Summarized briefly these are:
1. Disruption of behavioral patterns by construction
activities on almost all species would be lessened
considerably if construction took place during the winter,
November 15 to April 15. This would avoid most major
migrational, nesting or reproductive periods, and represents
the inactive period for grizzly and black bears. Increased
human activity and associated noises, aircraft activity, and
fires can be included as influxes that may be lessened by
proper timing.
2. The impact of destruction of sheep and moose
habitats by construction activities can be lessened by
avoiding the more important and sensitive habitat tyFes and
carrying out revegetation procedures on the disturbed right-
of-way as soon as possible.
3. The location of camps, comFressor stations, air
strips and supply and maintenance roads can be selected to
avoid adverse imFacts. If possible they should be placed
away from critical wildlife areas. Increased human activity
such as low-level aircraft flying, people on foot, cff-road
137
vehicle travel, hunting and trapping may have to be strictly
controlled within some sensitive areas.
4. All construction activities that may affect
drainage through obstructing, increasing or re-directing
normal surface and sub-surface water flows require great
caution in order to avoid adverse affects. Every attempt
should be made to know, understand and maintain the present
situation. Drainage structures must be adequate. Bridges are
preferred over culverts. Drainage in ditches should be
avoided.
5. The removal of gravel and sand from streambeds
should be avoided. If allowed, it should be conducted so as
to miminize damage to the riparian vegetation. Removal of
any material from the coastal sand bars should be strictly
prohibited.
6. The introduction of chemicals into the environment
in any form must be carefully reviewed and controlled.
Contingency plans must be devised that will allow quick
discovery and cont~ol of froblem situations.
7. The handling and disposal of garbage and sewage may
develop into a problem if inadequately carried out. Present
land-use regulaticns and highway campsite stipulations
should be closely followed.
8. The tund~a and muskeg areas are all very sensitive
to damage from t~acked construction equipment and all-
terrain vehicles. Excess damage can be avoided by
restricting their use to the construction right-of-way.
Long-term damage to wildlife populations and habitat
will not likely result from most construction activities
except for man-made fires, the removal of large gravel
material sources, and the establishment of large permanent
settlements in sensitive areas. If drainage conditions are
not seriously affected, little impact should be felt by most
inland waterfowl and aquatic furbearers.
Route selection will be the first and most important
step in alleviating impact on wildlife. If some sensitive
wildlife areas cannot be economically or physically avoided,
closer liaison between design engineers and biologists
should help lead tc a reduction of most disturbance features
of pipeline construction.
138
9. NEEDS FOR FURTHER STUtY
The current demand fer appraisals of the impact that
development activity will impose on wildlife resources
within the pipeline corridor emphasizes the need for more
detailed documentation of population-habitat relaticnships.
Both social and environmental values should be given
consideration in selecting the species that will be the
focus of further efforts.
9.1 Moose
Present inventory information should prove adequate for
the prediction of pipeline construction impact on moose.
More data would be helpful along the Mackenzie River itself,
particularly about the moose that winter on the islands.
Knowledge of their movement to and from these islands would
be useful.
9.2. Caribou
A sudden departure, in the fall of 1972, of the barren-
ground caribou of the Porcupine herd from the fairly stable
seasonal movement pattern documented during the previous two
years indicates the extreme variability and unpredictability
of caribou movements. Movements and chronology of mcvements
have been documented in detail for the Porcupine herd but
not for the other groups and sub-species. Better knowledge
of where and when these movements take place is necessary
before accurate predictions can be made on impact.
The effect of low-flying aircraft has not been clearly
enough documented to allow effective and reasonable
guidelines to be drawn up.
Reaction of migrating and non-migrating caribou to the
pipeline right-of-way, berms, roads, seismic lines, camps
and compressor stations requires more documentation.
In some cases, Farticularly during pipeline
construction, it may be advantageous to be able to control
or direct the movements of caribou around areas of pctential
conflict. No work has been done on developing economical and
effective techniques for this purpose.
In view of the above, the following aspects of caribou
population and behavior are being documented during the 1973
field season:
139
1. The size and composition of the various groups
2. The seascnal mcvement behavior
delineating wintering areas, calving areas,
and mineral licks whenever possible
and distribution
staging areas,
3. The productivity for 1973
4. The 1973 rortality and causes of death
5. The behavior to various disturbance sources,
particularly low-flying aircraft
6. Reaction to man-made deflection devices with the
aim of making recommendations for methods enabling the
small-scale manipulation of migration movements.
9.3 Dall Sheep
Since most Dall sheef are restricted to the mountainous
regions in the western part of the study area, they will be
well away from the proposed pipeline route and the effects
of construction should be minimal. However, in the
Richardson Mountains, the proposed route passes very near
some important wintering areas of the Mount Goodenough sheep
population. Pipeline construction activities in this area
could te very disturbing.
Much more detailed information is needed on habitat
requirements and behavior. The following information should
be documented:
1. The numbers and distribution of Dall sheep in the
Mount Goodenough area, particularly on the eastern slopes
2. Seasonal use of various parts of the
especially in the winter period and during lambing.
range,
3. The location and use made of all mineral licks in
the Mount Goodenough area.
4. More detailed descriptive data of the physical and
vegetational characteristics of the areas showing highest
use, especially the wintering areas, lambing areas and
mineral licks.
5. A systematic assessment of the reaction of Dall
sheep to aircraft. Low-flying aircraft represent one of the
most serious potential disturbance factors to sheep. Some
140
aircraft are more disturbing than others and the amount of
reaction varies with the time of year. In order to set
adequate stipulaticns more data are required.
9.4 Grizzly Bears
Preliminary surveys indicate that grizzly bears are
widely distributed throughout the study areas but are mainly
concentrated in the rough broken terrain of the mountains
and hilly regions and the northern tundra. Sightings were
most numerous in the mountainous regions of the northern
Yukon. The suspected large home range of adult male
grizzlies and their association with migrating caribou
suggests that a large numter of bears, through their wide
movements, may ccme in close contact with the pipeline and
pipeline activities.
Den sites are an important aspect of grizzly bear
habitat. Very few dens were located and little is known
about their physical characteristics.
In view of the potential interrelationships
grizzly bears and the proposed gas pipeline,
recommended that the following be documented:
between
it is
1. The home range and movement behavior of sex and age
groups of grizzly bears in the northern Yukon.
2. The association or relationship of grizzlies and
their movements with the Porcupine Caribou herd.
3. The location and ecological characteristics of
denning sites.
4. Population numbers and composition, productivity,
annual cycle, food habits and bio-energetics of the grizzly
bears in the northern Yukcn.
9.5 Arctic Fox
There is little need for further inventory work on
arctic foxes at this time. The widespread distribution of
maternal den sites and other important features of arctic
fox habitat requirements throughout the tundra areas of the
pipeline route indicate few direct problems. A ground
inspection of the pipeline right-of-way and material sources
once these locations are proposed in detail should help
reduce most disturbance problems.
141
9.6 Beaver and Muskrat
Preliminary habitat inventories indicate the more
important areas for muskrat populations are high-density
wetlands, areas that are generally avoided in the froposed
pipeline alignment. conversely, drainages that are occupied
by beaver populations are frequently crossed by the same
alignment. Further indications of the need to place emphasis
on beaver habitat studies are found in the greater influence
that teaver impose on the environment through their efforts
to control water levels. Finally, it is probable that beaver
populations will be much more sensitive than muskrat to
accelerated harvest programs that may accompany increased
access.
During the current field season, the following aspects
of beaver populations and habitat, within the immediate
pipeline corridor, should be documented through both aerial
and ground surveys:
1. Intensity of beaver activity on individual streams
and stream systems directly in line with current pipeline
alignment.
2. More details of the physical and vegetational
characteristics of those areas showing highest use-density.
Physical features could include stream size and gradient,
channel form, bank stability and substrate materials.
Vegetational features tc be documented include composition
of woody plant communities in close proximity to stream
channels, and species composition of the plants utilized by
beaver within the range of available habitat types.
3. The influence that beaver exert on landscafes, as
seen in the gross aspects of vegetational communities above
and below dam-sites.
4. The use of beaver habitat by other species, such as
muskrats, waterfowl, mink, moose, etc.
Further understanding of these relationships will be
beneficial not only from the standpoint of impact prediction
but also as input into continued management programs.
9.7 Waterfowl
The present inventory of waterfowl habitat delineates
the location of individual wetlands and wetland complexes in
142
the detail believed to be required to pinpoint most
potential areas of conflict with proposed major
developments. Nevertheless, for more detailed assessments,
it will be necessary to upgrade and obtain additional
information to formulate more conclusive "values" both
qualitative and quantitative -for specific localized areas.
It will be practical to focus attention on a very
limited portion of the inventory study area -the froposed
pipeline corridor. Additional studies in 1973 are being
confined to wetlands within what may be termed a •zone of
influence• of the tentative gas pipeline right-of-way.
Some inventory ratings have, of necessity, been made
with information of a general nature. Studies should now
focus on details such as species and densities of birds
utilizing individual units; and specific criteria, such as
favored vegetation species, which may influence use. Results
of such studies will support the present inventory and they
may be extrapolated to provide insight for similar areas
within the 1972 study area.
Aerial and ground SUfport equipment for pipeline
construction and mcnitoring will, if used at random, harass
some waterfowl causing less of production. Restrictions are
necessary to minimize machinery waterfowl encounters.
Presently, several short-term studies provide superficial
results of waterfowl reaction to such disturbance. However,
as wildlife behavioral responses depend on reactions to
complex internal and external stimuli and physiological
condition, long-term research is needed to fully understand
the problems. Such studies would be too late to employ in
advance of pipeline developments. To better understand how
large flocks of birds react to aircraft, a study is planned
for the North Slope where flocks of snow geese will be
subjected to aircraft over-flights and reactions will be
documented under varied conditions.
A very impcrtant factor which could be used in
predicting change or "imfact'' on waterfowl habitat is
adequate insight into the status of hydrological regimes
prior to disturbance. If at least some such information can
be made available from other environmental and engineering
specialists, detailed impact assessments should reflect in
accuracy of forecasts.
9.8 Raptors
Few raptors should be directly influenced by the
143
presence of a gas Fipeline. It will be the indirect wide-
ranging influences such as human presence, noise, and the
use of open cliff faces for material sources that will have
the most impact on this species. Nesting sites as far away
as 2 or 3 miles on each side of any pipeline activity may be
influenced.
The efforts expended in locating raptor nest sites
during the past season were insufficient to give mere than
an indication of the potential problems. More information is
needed on nest locations, critical breeding pericds and
types of prey species utilized before speculations on the
effects of human activity can be provided.
144
10.1 Literature Cited
Aldous, s. E. 19q4. A Deer Browse Survey Method. Journal of
Mammalogy 25:130-136.
Banfield, A. w.
Caribou, Genus
Bulletin 177.
F. 1962. A Revision of the Reindeer and
Rangifer. National Museum of Canada
Barry, T. w., and R. Spencer. 1972. Wildlife Response to Oil
Well Drilling. canadian Wildlife Service Preliminary
Manuscript, 44 pp.
Benson, w. A. 1965. outline of the canadian Land Capability
Classification for Wildlife. Canada Land Inventory,
ARDA, Technical Report.
de Belle, s. G., P. H. Beaubier and s. D. Thompson. 1972.
Land Use Information Series. 44 mapsheets at a scale of
1:250,000. Produced by the Land Use Planning Branch,
Environment canada, Ottawa, for the Dept. of Indian and
Northern Affairs.
Edwards, R. Y., and R. W. Ritcey. 1956. The Migrations of a
Moose Herd. Journal of Mammalogy 37:486-494.
Geist, v. 1971. Is Big Game Harassment Harmful? Oilweek
(Calgary) 22(17):12-13.
Hall, E. R., and K. R. Kelson. 1959. The Mammals of North
America. The Ronald Press Company.
Hulten, Eric. 1968. Flora of Alaska and Neighboring
Territories. Stanford University Press.
Kelsall, J. P. 1968. The Migratory Barren-ground caribou of
Canada. The Queen's Printer, Ottawa.
145
Macpherson, A. H. 1969. The dynamics of canadian arctic fox
populations. Canadian Wildlife Service Beport Series
No. 8.
Benewable Besources Consulting Services Ltd. 1971. A Study
of the Porcupine caribou Herd. Northwest Project
Wildlife Studies Technical Report, 3 vols.
146
10.2 General References
canada Dept. of Transport, Meteorological Branch. 1967.
Temperature and Precipitation Tables for the north
Yukon Territory and Northwest Territories.
Crampton, c. B. 1973. Studies of Vegetation, Landform and
Permafrost in the Mackenzie Valley: Landscape survey in
the Upper and Central Mackenzie Valley. Environmental-
Social Committee, Northern Pipelines, Task Force on
Northern Oil tevelopment, Ottawa. 35 pp. + maps.
de Belle, s. G., P. H. Beaubier and s. D. Thompson. 1972.
Land Use Information Series. 44 mapsheets at a scale of
1:250,000. Produced by Land Use Planning Branch,
Environment Canada, Ottawa for Dept. of Indian and
Northern Affairs.
Douglas, R. J. W. (Ed .. ) 1970. Geology and Economic Minerals
of Canada. Economic Geology Report No. 1, Canada Dept.
of Energy, Mines and Resources.
Forest Management Institute. 1973. Vegetation types of the
Mackenzie Corridor. 1:125,000. Canadian Forestry
Service, Environment Canada. An Open File,
Environmental-Social Committee, Northern Pipelines,
Task Force on Northern Oil Development, Ottawa.
Geological Survey of Canada: surficial Geology Maps 96C, D,
E, F, L; 97C, D; 106G, H. I, J, O, P; 117A, C, D.
Government of Canada. 1957. Atlas of canada. Dept. of Mines
and Technical Surveys, Geographical Branch, Ottawa.
Government of Canada. 1970. Arctic Ecology Map Series.
canadian Wildlife Service.
Potter, J. G. 1965. snow Cover. Climatological Studies No.
3; Canada Dept. of Transport, Meteorological Branch.
147
:Rowe, J. s. 1972. Forest :Regions of canada. Dept. of
Environment, canadian Forestry Service. Publication No.
1300, 1972.
u. s. Fish and Wildlife Service. :Raw data from Annual
Waterfowl Breeding Pair Surveys, N.W.T. 1970-1971.
Zoltai, s. c., and w. w. Pettapiece. 1973. Studies of
Vegetation, Landform and Permafrost in the Mackenzie
Valley: Terrain, Vegetation and Peimafrost
:Relationships in the Northern Part of the Mackenzie
Valley and the Northern Yukon. :Report 73-4,
Environmental-Social Committee, Northern Pipelines,
Task Force on Northern Oil Development, Ottawa.
11. APPENDICES
11.1 Appendix I
List of Scientific Names of Plants Referred to in this Report, Including
Accompanying Atlases (Hulten, E. 1968).
Common Name Scientific Name
Alder Alnus crispa
Aquatic Moss Musci spp.
Aspen Poplar Populus tremuloides
Balsam Poplar Populus balsamifera
Black Spruce Picea mariana
Bog Bilberry Vaccinium uliginosum
Bog or Dwarf Birch Betula glandulosa
148
Bog Cranberry Vaccinium vitis -idaea
Buffalo berry Shepherdia canadensis
Bulrush Scirpus spp.
Bur Reed Sparganium angustifolium
Cattail Typha latifolia
Cloudberry Rubus acaulis
Rubus chamaemorus
Coontail Ceratophyllum demersum
Cottongrass Eriophorium angustifolium
Dewberry Rubus pubescens
Duckweed Lemna spp.
Dwarf Birch Betula nana
Horsetail Equisetum spp.
Jack Pine Pinus banksiana
Common Name
Juniper
Labrador Tea
Larch
Marestail
Marsh Cinquefoil
Mountain Aven
Pondweeds
Red Osier Dogwood
Rose
Saskatoon
Sedge
Spike rush
Snowberry
Water Arum
Water Li 1 y
Water Milfoil
Water Smartweed
White Birch
White Spruce
Wild Red Raspberry
Willow
Scientific Name
Juniperus spp.
149
Ledum decumbens, ~· groenlandicum
Larix 1 a r i c ina --
Hippuris vulgaris
Potentilla palustris
Dryas spp.
Potamogeton spp.
Cornus stolonifera
Rosa acicularis
Amelanchier alnifolia
Carex spp.
Eleocharis palustris
Symphoricarpos albus
C a 11 a pa 1 us t r i s
Nuphar variegatum
Myriophyllum exalbescens
Polygonum spp.
Betula papyrifera
Picea glauca
Rubus idaeus
Salix spp.
150
1 l . 2 Appendix I I
Table 1. The potential effects of the proposed Mackenzie Valley Gas Pipeline
construction activities.
Construction Activity Potential Effect
Habitat Destruction or Loss
Pipeline right-of-
way
Buried refrigerated
gas lines
Camp locations
Borrow pit
construction
locations
Removal of sand
and gravel along
water bodies and
streams
Removal of
coastal sand bars
Stream crossings
Berms and road
grades
Destruction of
habitat
Change in
aquatic thermal
regime
Loss of habitat
Loss of habitat
Removal of
riparian
vegetation
Sedimentation
Loss of habitat
Introduction of
sediment loads
and erosion of
stream banks
Ora i nage of
adjacent ponds
Obstruction and/
or redirection
of normal surface
and sub-surface
water flows
Changes in
sediment loads
Species
Affected
Sheep
Moose
Beaver
Muskrat
Waterfowl
Moose
Rap tors
Bear
Fox
Sheep
Beaver
Muskrat
Waterfowl
Moose
Muskrat
Waterfowl
Beaver
Muskrat
Waterfowl
Muskrat
Waterfowl
Beaver
Muskrat
Waterfowl
Beaver
Muskrat
Waterfowl
Magnitude
Severe
Light
Variable
Variable
Moderate
Light
Severe
Light
Light
Light
Variable
Variable
Severe
Severe
Light
Severe
Moderate
Moderate
Moderate
Severe
Severe
Variable
Variable
Moderate
Variable
Variable
Severe
Duration
Short
Short
Long
Long
Short
Long
Long
Long
Long
Long
Short
Long
Long
Long
Moderate
Long
Long
Long
Long
151
11 . 2 Con t • d .
Table 1. Cont 1 d.
Construction Activity Potential Effect Species Magnitude Duration
Affected
Ditching Changes in normal Beaver Variable
surface or sub-Muskrat Variable
surface water flow Waterfowl Severe long
Increased fires loss of habitat Beaver Moderate Moderate
Waterfowl Moderate Short
Caribou Severe long
Moose Severe Short
Use of all-terrain Terrain damage Caribou light long
vehicles
DisruEtion of Normal Behavior Patterns
Berms and road Creating travel Caribou Moderate long
grades lanes changing Moose light long
direction and
resulting in
damage to berm
and surrounding
terrain
Creates snow Caribou Moderate long
drifting Moose light long
obstructs
movement
Borrow pit Activity, blasting Bear light Short
construction noise Sheep Moderate Moderate
Waterfowl Moderate Short
Caribou Moderate Short
Moose light Short
Raptors Severe Moderate
Ditching Open ditch during Caribou Severe Short
construction Moose light Short
Rec 1 amat ion Attract animals Moose light long
procedures to areas where
they are more
vulnerable and
away from traditional
habitat
Operation of engine Noise Beaver light Short
driven equipment Muskrat light Short
Sheep Severe Short
Waterfowl Severe Short
Caribou Moderate Short
Raptors SevPre Short
11 . 2 Con t 1 d .
Table 1 Cont'd.
Construction Activity
Garbage and sewage
disposal
Increased Human Activity
Aircraft support
Use of all-terrain
vehicles
Human activity
(camps, etc.)
{Roads, trails,
airstrips)
Introduction of
pollutants, fuels,
oils, toxic chemicals
Potential Effect
Attraction of
animals
Aerial harassment
Harassment
Disturbance due
to human presence
Increased hunting
and trapping
(variable with
a 11 species
depending on the
regulatory
control of
harvest)
Direct and
indirect poisoning
Species
Affected
Bears
Foxes
Bear
Sheep
Waterfowl
Caribou
Moose
Bear
Fox
Sheep
Waterfowl
Caribou
Moose
Sheep
Caribou
Moose
Raptors
Beaver
Muskrat
Bears
Foxes
Sheep
Waterfowl
Caribou
Moose
Rap tors
Beaver
Muskrat
Waterfowl
Rap tors
Magnitude
Severe
Moderate
Moderate
Severe
Severe
Severe
Moderate
Moderate
Light
Severe
Moderate
Severe
Light
Moderate
Light
Light
Severe
Variable
Variable
Severe
Moderate
Severe
Light
Moderate
Moderate
Severe
Moderate
Severe
Severe
Severe
152
Duration
Moderate
Short
Short
Moderate
Short
Moderate
Short
Short
Short
Moderate
Short
Short
Short
Short
Short
Short
Long
Long
Moderate
Moderate
Short
Moderate
Moderate
Long
Short
Short
Short
Long