HomeMy WebLinkAboutAPA396SUSITNA HYDROELECTRIC PROJECT
Prepared for:
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ENVIRONMENTAL REPORT
TASK 7: ENVIRONMENTAL
FURBEARERS -1980
MAY 1981
Prepared by :
Teffe1trial
Environmental
Speciali1tl., Inc.
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L----ALASKA POWER AUTHO~~~~.~ TTn"!·,,_,~__,
Librarv & lnfonnation Services
Anchorage, A.laska
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
ENVIRONMENTAL STUDIES ANNUAL REPORT 1980
SUBTASK 7. 11 WILDLIFE ECOLOGY
FURBEARERS
MAY 1981
by
ALASKA COOPERATIVE WILDLIFE RESEARCH UNIT
Fairbanks, Alaska 99701
and
TERRESTRIAL ENVIRONMENTAL SPECIALISTS, Inc.
Phoenix, New York 13135
for
ACRES AMERICAN, INCORPORATED
Liberty Bank Building, Main at~~][~
Buffalo, New York 14202 k R Alas a esources
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Library & Information Services
Anchorage, Alaska
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SUSITNA HYDROELECTRIC PROJECT
FORBEARER STUDIES
ANNUAL REPORT
(January -December 1980)
To:
TERRESTRIAL ENVIRONMENTAL SPECIALISTS, INC.
PRINCIPAL INVESTIGATOR
PHILIP S. GIPSON
GRADUATE RESEARCH FELLOWS
STEVEN W. BUSKIRK
T. WINSTON HOBGOOD
FIELD ASSISTANTS
DONALD VERNAM
JOSEPH KRUGER
NANCY PAWLAK
MATIHEW HARE
ALASKA COOPERATIVE
WILDLIFE RESEARCH UNIT
SUMMARY
Progress was made upon all aspects of furbearer and habitat inventories
and impact assessments during the first year of investigation. Emphasis
was placed upon population surveys and seasonal furbearer/habitat rela-
tionships. Furbearers that may inhabit the impact areas include red
fox, coyote, lynx, mink, pine marten, river otter, short-tailed weasel,
least weasel, muskrat and beaver.
General estimates of furbearer abundance and habitat use during periods
of snow cover were based upon aerial transects and aerial checks of
lakes and ponds. Surveys of aquatic furbearers were conducted from a
riverboat during August from Devil Canyon to the Kashwitna River.
Movements of individual foxes, marten and mink, and their preference for
particular habitats were monitored by radio telemetry. Diets of carnivorous
furbearers were investigated by identifying food remains in their droppings
and food remains in the digestive tracts of furbearers taken by trappers
in the area.
Populations of all furbearers identified for investigation exist within
the impoundment areas and along the Susitna River from Devil Canyon to
Cook Inlet, however, numbers of coyotes and lynx are low. Beavers and
muskrats are present along much of the river and its main tributaries.
Beaver numbers increase progressively from Devil Canyon downstream to
the confluence of the Kashwitna River.
A total of five red foxes were outfitted with collars containing radio
transmitters. Red foxes in the study area used dens later in the
autumn than has previously been reported for foxes. Some red foxes
appear to utilize shores of the Susitna River and deltas of tributaries
during summer and autumn, then shift to alpine zones in winter as snow
depth increases along the river. Other foxes appear to remain above
timberline throughout the year.
Four pine marten and two mink were radio-collared during 1980. It
appears that adult male marten have mutually exclusive home ranges
during summer with creeks in some cases forming boundaries of the home
ranges. The activity data gathered during autumn suggest that marten at
that time are generally nocturnal with a minor activity peak around
noon.
Loss of habitat and reductions in furbearer numbers may be expected in
areas inundated~ where roads are constructed, and at borrow pits. We
expect that pine marten will be most severely impacted, followed in
decreasing order by mink, fox, otter and weasel. High levels of human
activity and noise pollution during furbearer breeding and denning
seasons could severely alter reproductive success of all species.
Projected changes in flow rates of the Susitna River downstream from the
Devil Canyon impoundment could result in marked changes in the habitats
available to aquatic furbearers. Beaver and muskrat could benefit from
delayed freeze-up in autumn and possibly benefit from more stable rates
of flow. The anticipated seasonal drawdown of the Watana impoundment is
likely to have a marked negative impact upon beaver, muskrat, mink, and
river otter that inhabit the Watana impoundment area.
Changes in impoundment design to lower and/or stabilize the pool levels
wi 11 benefit fu rbea rers by reducing 1 ass of foraging and denni ng habitats.
Loss of habitat from construction of dams, borrow pits, access roads and
diversion tunnels can be minimized by utilizing borrow and fill sites as
close as possible to actual construction. Regarding the access route to
impoundment sites, we believe the best access route would be Corridor 2,
south of the river to Devil Canyon, then across the river and follow
Corridor 1 from Devil Canyon to the Watana site. If only the Watana dam
is to be constructed, Corridor 3 from the Watana site to the Denali
Highway would be preferred.
Creek drainages and adjacent areas are extremely important to furbearers.
We recommend that access roads and construction activities be outside
creek valleys when practical.
TABLE OF CONTENTS
Page
1 -INTRODUCTION-------------------------------------------------1
1.1 Objectives for Phase 1---------------------------------1
1.2 Tasks for the period January-December 1980------------2
2 -METHODOLOGY-----.---------------------------------------------3
2.1 Literature Review--------------------------------------3
2.2 Muskrat and Beaver Surveys-----------------------------3
2.3 Fox Den Surveys----------------------------------------3
2.4 Live Trapping and Radio-collaring----------------------. 4
2.5 Fo11owin~ Fox Trails-----------------------------------4
2. 6 Food Habits Studies------------------------------------7
2. 7 Aerial Transects---------------------------------------7
2.8 Downstream Furbearer Surveys---------------------------9
2.9 Otter and Mink Surveys---------------------------------10
3 -RESULTS AND DISCUSSION OF BASELINE STUDY---------------------11
3.1 Literature Review--------------------------------------11
3.2 Muskrat and Beaver Surveys-----------------------------11
3.3 Fox Den Surveys----------------------------------------17
3.4 Live Trapping and Radio-collaring----------------~-----19
3. 5 Fo 11 owing Fox Tra i 1 s -----------------------------------29
3.6 Food Habits Studies------------------------------------29
3.7 Aerial Transects---------------------------------------29
3.8 Downstream Furbearer Surveys---------------------------29
3.9 Otter and Mink Surveys---------------------------------31
3.10 Other Furbearers ---------------------------------------31
4 -IMPACT ASSESSMENT---------------------------------------------34
4.1 Construction Impacts-----------------------------------34
4.2 Operation Impacts--------------------------------------36
Page
5 -MITIGATION --------------------------------------------------40
6 -REFERENCES -""-------------------------------------------------42
7 -AUTHORITIES CONTACTED---------------------------------------44
LIST OF TABLES
No. Title
1)
2)
3)
Sample fox trail data sheet. --------------------------------------
Results of surveys for muskrat pushups, spring, 1980.-------------
Background infonnation for captured foxes.------------------------
4) Summary of necropsies of 9 red fox carcasses obtained from
Don Newman and Mary Kay McDonald. All of the foxes were
trapped within 20 miles of Adventures Unlimited Lodge, mile
Page
6
12
20
100 Denali Highway.------------------------------------------------24
5) Background infonnation for radio-collared mustelids, Tsusena
Creek Study area.--------------------------------------------------26
6) Occurrence of beaver signs along 3 sections of the lower Susitna
River: Section I = Devil Canyon to confluence with Talkeetna
and Chulitna Rivers, Section II= confluence with Talkeetna
and Chulitna Rivers to confluence with Montana Creek, Section
III = confluence with Montana Creek to Cook Inlet.----------------30
7) Results of otter and mink surveys, Susitna River, 10 November-
12 November 1980.--------------------------------------------------32
LIST OF FIGURES
No. Title Page
1) Susitna Basin. Study area for assessing probable ·impacts of
the Susitna Hydroelectric project upon furbearers indicated
by hatching.-------------------------------------------------------4
2) Aerial transects for furbearers (A) and checkpoints for
signs of otter and mink (OM). ----------------------... --------------8
3) Locations of fox dens discovered during 1980 and minimum
home ranges of 3 radio-collared foxes. ----------------------------18
4) Tracking locations for 4 radio-collared marten.--------------------27
5) Daily activity pattern data for 3 adult male marten.--------------28
1 -INTRODUCTION
This report summarizes the progress made during the first year of Phase
I studies by the team investigating impacts upon furbearers. One additional
year of Phase I investigations will be completed before Phase II studies
are initiated. Objectives and specific tasks of Phase I studies are
reviewed below.
Phase I studies of furbearers are designed to detennine probable impacts
of the proposed Susitna·Hydroelectric Project upon the following species:
Red fox, Vulpes fulva; coyote, Canis latrans; lynx, Lynx canadensis;
mink, Mustela vison; pine marten, ~1artes americana; river otter, Lutra
canadensis; short-tailed weasel, Mustela enninea; least weasel, Mustela
nivalis; muskrat, Ondatra zibethica and beaver, Castor canadensis.
1.1 -Objectives for Phase I
(a). Determine general abundance of each species in the study area.
(b). Assess habitat preferences of each species.
(c). Analyze seasonal use of habitats and degree and type of utilization
of habitats for each species.
(d). Project the probable impacts of the proposed development on each
species.
(i). Assess likely changes in habitats from the proposed action.
(ii). Project changes in abundance of furbearers in response to
habitat changes.
(iii). Predict other, non-habitat related impacts upon furbearers.
1. 2 -Tasks for the period Januarv-December 1980
(a). Review of literature.
(b). Familiarize the study team with the study area.
(c). Design a viable sampling scheme for the impoundment zones~ areas
adjacent to the impoundments, and downstream areas.
(d). Conduct baseline surveys of furbearer populations and furbearer and
habitat relations.
(i). Generate infonnation on activity patterns and home range size
and shape of elusive furbearers.
(ii). Provide infonnation on furbearer distribution and movements,
especially during snow-free periods of the year.
(iii). Detennine preferred seasonal habitats.
(e). Consult with residents, trappers, scientists, government officials
and others who are knowledgeable of the Susitna area or similar
areas or knowledgeable in a discipline pertinent to our research.
(f). Develop close working relations with other professional study teams
conducting studies related to probable impacts of the hydroelectric
project upon resources.
(g). Provide infonnation as needed to aid in developing recommendations
for mitigation and development proposals including alternative
access routes, borrow sites and transmission line corridors.
(h). Participate in public meetings and provide information to the media
as appropriate and as approved to inform the public about progress
of the study.
2
2 -MEiHODOLOGY
The study area for this project was defined as the Corps of Engineers
proposed impoundment zones, land and water areas within 12 kilometers
(7.5 miles) of the impoundment zones and the downstream flood plain to
Delta Islands (Figure 1).
2.1 -Literature Review
Literature searches have been carried on through the first year of Phase
I studies. Computer bibliographic searches as well as manual searches
of literature, indices and private reprint libraries have been employed.
2.2 -Muskrat and Beaver Surveys
In spring 1980, just prior to break-up, a survey of lakes and ponds in
the study area was conducted to determine the presence and relative
numbers of muskrats and beavers present during winter~
for muskrat push-ups and beaver sign were conducted on
spring 1980. An initial survey was made on 10 March.
Aerial searches
three dates in
Forty-five lakes
and ponds were surveyed on this date, requiring 6.0 hours of fiying time
in a Bell 206 helicopter. The snow cover on many lakes was still too
deep to permit positive identification of muskrat push-ups. A second
attempt was made on 24 April, however, deep snow was still present on
some lakes. A third attempt was made on 9 May. On this date the weather
was clear and the melt of snow and ice had progressed to a point that
permitted optimum sightings of push-ups. Ninety-seven lakes were surveyed
in 6.9 hours. Lakes surveyed were below 850 meters (2800 feet) in
elevation and they were within the proposed impoundment zones or 4.8 km
(3 miles) thereof. Lakes within 4.8 km (3 miles) of the Susitna River
were surveyed as far downstream as Gold Creek.
2.3 -Fox den surveys
Aerial searches for active red fox dens were made in areas that appeared
to offer suitable denning sites: well-drained, south-facing slopes with
.3
___ _s ~
I ----
MIL.ES
0 10 20 30 40 50
KtL.OMETERS
0 25 50
Figure 1.
Susitna Basin. Study area for assessing probable impacts of the Susitna
Hydroelectric project upon furbearers indicated by hatching. During 1980
study efforts extended downstream as far as the Kashwitna River.
fine soil. Valuable reports of active fox dens were obtained from other
TES and Acres researchers. Locations of active and inactive fox dens
were plotted on 1:639360 scale maps.
2.4 -Live trapping and radio-collaring
Red foxes were captured with leg hold traps and outfitted with radio-
collars. Foxes were radio-located from the ground and from aircraft
using yagi antennas and radio receivers. Locations were plotted on
1:63,360 scale maps.
Marten were trapped on an opportunistic basis using Tomahawk 811 X8 11 X29 11
live traps and a variety of baits and lures. A total of 24 traps were
taken to the study area, but generally 2 to 12 were set on any particular
night depending upon manpower available and specific trapping objectives
for the night. At times only 2-4 traps were set to recapture radio-
collared marten to replace radios with weak batteries.
Marten and mink were radio-collared on an intensive study site at the
mouth of Tsusena Creek. Mink and marten were radio-located from the
ground and from aircraft using yagi antennas and radio receivers.
Locations of mustelids were plotted on 1:24,000 scale maps. Activity
patterns of mink and marten were monitored from 24 September to 20 October.
Fluctuations in signal strength were used to differentiate between
activity and inactivity. Four 24-hour activity watches were conducted.
2.5 -Following fox trails
Fox trails were followed when fresh snow was present. When followed on
foot or snow shoes, each fox trail was sampled every 150 paces for snow
depth, snow hardness, vegetation, ,elevation, physiography, activity of
the animal .• and proximity to lakes, ponds, streams, or rivers. Other
noteworthy activities of the animal were recorded. for example, kill
sites or scent posts (Table l is a sample trail data sheet).
5
Table 1. Sample Fox Trail Data Sheet.
Name of Observer:
L4eather:
Collared Fox?
Sample Snow
Point Depth
2.5 11
2 65p. 2.5"
3 150 2.5
4 w/in 2.5"
12p.
5 150 2.5"
6 150 2.5"
7 w/in 2.5"
38p.
8 150 2.5 11
W. Hobgood
Partly cloudy
Yes No X
Vegetation
lake shore/bog
II II II
II II II
II II II
" " II
Date:
P:
Band
Mat cush exposed
boulders/rocks
II II II
Mat cush exposed
field of boulders
9 150 Deep snow II II II
10 150 Deep snow Tussocks, some
rocks
12 150 Deep snow Mat cush and
shrubs
1 0/ll/80
20°F
Channel
Physiography
lake shore
rock morph
II II
II II
II II
II II
II II
II II
II II
II II
II II
II II
Altitude: 3200 ~1Sl
Location: Swimming Bear lake
Within 50 Yds
Prey Species? Lake or Stream?
No Edge of Lake
No II II II
No lake within
100 yds
No Lake within
100 yds
No Within 50 yds
No Within 50 yds
No Within 50 yds
Yes Within 75 yds
Yes Within 100 yds
Yes 125 yds away
Yes 125 yds away
Sample Interval:
Date of last snow:
150 paces
10/11/80
Activity Comments
Wandering by edge
of lake
Scent post
Walking In areas of deep
snow he avoided
it by bounding
from tussock to
tussock
Investigating
ground sq den
Walking
Coming down hill Backtracking
along edges snow drift
Coming down hill Urine post
along edges
Coming down knob Investigated
squirrel hole at
144p.
Hopping along in
deep snow
Investigating Tracks of
gross clump ptarmigan tracks
within 20 yds
Running Determined this
fox observation
Oct. 10 from
helicopter
Aproximately 16 km {10 miles) of fox trails were followed in November
1980 at 2 locations, Swirraning Bear Lake vicinity and on the Tsusena-
Deadman bench, directly behind Watana Camp.
2.6 -Food habits studies
Studies of the food habits of furbearers were based upon field sign at
feeding sites, identification of food remains in scats, and identification
of food remains in stomachs and guts of carcasses obtained from trappers.
Scats of red foxes were collected at den sites and along fox trails.
Scats of mustel ids were collected from trails, successful 1 ive traps and
resting burrows which were located by telemetry. Carcasses of foxes,
marten, mink, and short-tailed weasels taken by trappers near the study
area were necropsied for additional dietary data. A total of 43 marten,
mink and short-tailed weasels were necropsied for stomach and intestinal
contents. Teeth of these animals were saved for later age studies.
Similarly, 10 red foxes were necropsied. Scats and gastrointestinal
tract contents. of furbearers have been dried and will be analyzed in
sunnner 1981.
2.7 -Aerial transects
A system of snow transects was developed early in spring 1980 and altered
during autumn to sample a wider area and provide a broad overview of
furbearer distribution and habitat preference. The revised transects
are 9.6 km {6 miles) long and perpendicular to the river (Figure 2).
The transects extend 4.8 km (3 miles) south and 4.8 km (3 miles) north
of the Susitna River. Fourteen transects occur at intervals of 9.6 km
(6 miles) from Portage Creek to the Tyone R.iver (Figure 2).
To run the transects, a helicopter carrying 2 observers and a person to
record observations is flown along the transect at 24-32 kmph (15-20
mph) at treetop level or the lowest possible a1titude, generally 10-20 m
(30-60 feet). Tracks of furbearers are observed and counted as crossed
along the flight path. The following are recorded each time the trail
7
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0 ,o!l
val
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SUSITNA
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Fairbonks "1.: "1.
0 -.~,<!: ~ ""·"" ~8 \u
cree~
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RIVER
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Cree~
0
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0
1
<t:
10
I
15
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20 km
I
t
Figure 2. Aerial transects for furbearers {A) and checkpoints for signs of otter and mink (OM).
of a furbearer is crossed: the species of the furbearer, the vegetation
type and the 100 foot elevation contour in which the trail was found.
To determine accuracy of track identification, ground truth checks were
conducted on 3 transects. Team members walked along transects
shortly after the transects were run by helicopter. Data recorded were
the same as those recorded from aircraft.
2.8 -Downstream furbearer surveys
Furbearer sign and habitat use preferences were inventoried along the
Susitna River during August 1980 from 3 km (1.9 miles) above the confluence
with the Indian River to 4 km (2.5 miles) below the confluence with the
Kashwitna River (Figure 1). This survey included portions of the three
major river habitat types below Devil Canyon, including:
(a). Section I. .. Devil Canyon to confluence with Talkeetna and Chulitna
Rivers. Characterized by rapid flow, usually single channel,
narrow flood plain with occasional stands of mature forests.
(b). Section II. -Confluence with Talkeetn~ and Chulitna Rivers to
confluence with Montana Creek. Characterized by meandering channels,
broad flood plain with forested shores and islands.
(c). Section III. .. Confluence with Montana Creek to Cook Inlet. Characterized
by broad meandering and braided channels, numerous sloughs and
oxbow lakes, broad flood plain with heavily forested shores, islands
and tributary deltas.
Observations of furbearers and their signs along the Susitna River were
made from a 24-foot riverboat. Numerous stops were made to verify signs
observed. Two observers called out animals and sign sighted on opposite
sides of the boat. A third team member recorded observations and noted
locations on maps. Data were then tabulated according to river mile.
9
2.9 -Otter ~nd mink surveys
An unusually high incidence of otter sign was noted along the Susitna
' River for a short period in November. To document this occurrence of
sign, check points were established at intervals of 4 km (2.5 miles)
along the Susitna River from Portage Creek to the Oshetna River (Figure
2).
10
3 -RESULTS AND DISCUSSION OF BASELINE STUDY
3.1 -Literature Review
Over 350 references relating to furbearers and hydroelectric development
have been co11ected and reviewed. Only a small portion of this literature
treats impact assessment in northern regions. A symposium in Ottawa,
Ontario on 7 and 8 January 1974, reviewed major hydroelectric projects
in Canada and the impact assessments made for these projects. Proceedings
of this symposium were published in the Journal of Fishery Research
Board of Canada, Volume 32, number 1. Baxter and Glaude (1980) also reviewed
environmental effects of dams and impoundments in Canada. Probably the
most extensive study of impacts of a proposed hydroelectric project in
Alaska was directed at the Rampart Canyon Dam on the Yukon River (Spurr
1966, Leopold 1966). Recently the Arctic Environmental Infonnation and
Data Center (1980) reported their assessment of probable environmental
effects of constructing and operating the Terror Lake hydroelectric
facility on Kodiak Island. A team working with Konkel (1980) modified a
\videly used terrestrial habitat evaluation system for Alaska and developed
a handbook to be used in assessing the importance of habitats for some
Alaskan wildlife species.
Published accounts treating the life requisites of furbearers in Alaska
and probable effects of environmental alterations upon furbearers are
reviewed in the discussion sections of this report treating particular
furbearers.
3.2 -Muskrat and Beaver Surveys
Findings of the spring surveys for muskrats in impoundment zones are
summarized in Table 2. The beaver and muskrat surveys in May, plus
observations by team members on shuttle flights and sightings reported
by helicopter pilots and other project personnel, indicated that populations
of these species occur along much of the Susitna River and its main
tributaries. Sign of these animals was most visible in early spring
11
Table 2. Results of Surveys for Muskrat Pushups, Spring, 1980.
Locations of Lakes
Lake E1 evati on No. Quarter
number MSL eushues section Section Range Towns hie
001 875 2 sw 31 lW 32N
SE 31 lW 32N
002 1550 4 SE 30 1W 32N sw 29 1W 32N
003 1725 14 NE 30 lW 32N
NW 29 1W 32N
004 2100 0 NE 20 lW 32N
NW 21 1W 32N
SE 20 1W 32N
005 1640 26 SE 15 1W 32N sw 14 1W 32N
SE 14 1W 32N
NW 23 lW 32N
006 1625 0 NW 23 1W 32N
NE 23 1W 32N
007 1575 0 NW 24 lW 32N sw 24 lW 32N
SE 23 1W 32N
NE 23 1W 32N
008 1520 0 sw 6 1E 31N
009 1520 0 SE 6 1E 31N
010 1450 0 sw 32 lE 32N
011 1550 0 SE 32 1E 32N
012 1375 0 SE 32 1E 32N
013 1780 0 sw 4 1E 32N
SE 4 1E 32N
014 2375 0 NW 28 1E 32N
015 2375 0 NE 21 1E 32N
NW 22 lE 32N sw 22 lE 32N
NW 27 1E 32N
SE 21 1E 32N
016 2335 D sw 16 1E 32N
SE 16 1E 32N sw 15 lE 32N
NW 22 1E 32N
NE 21 1E 32N
017 2475 0 NE 22 1E 32N
NW 23 1E 32N
018 1875 0 NW 35 1E 32N
019 1650 0 sw 35 lE 32N
NW 2 lE 31N
020 1775 0 SE 35 1E 32N
NE 2 1E 31N
Locations of Lakes
Lake Elevation No. Quarter
number MSL pushups section Section Range Township
021 2375 0 NW 36 lE 32N
022 2375 0 NW 36 1E 32N
023 2250 0 sw 24 lE 32N
SE 24 lE 32N sw 19 2E 32N
NW 30 2E 32N
NE 25 1E 32N
NW 25 lE 32N
024 2375 0 NE 19 2E 32N
NW 20 2E 32N
025 2370 0 NW 20 2E 32N
NE 20 2E 32N
SE 20 2E 32N sw 20 2E 32N
026 2325 0 sw 21 2E 32N
027 1750 0 NW 27 2E 32N
NE 27 2E 32N
SE 27 2E 32N sw 27 2E 32N
028 2475 0 NE 7 4E 31N
029 2350 0 sw 8 4E 31N
030 1975 0 NW 17 4E 31N
031 1975 0 NE 17 4E 31N
032 2275 1 NW 5 5E 31N sw .5 SE 31N
033 2275 0 sw 5 5E 31 N
034 2350 0 sw 4 SE 31N
SE 5 SE 31N
035 2230 0 sw 9 SE 31N
SE 9 SE 31N
NE 16 SE 31N
NW 16 5E 31N
NE 17 5E 31N
NW 17 5E 31N
NE 18 5£ 31N
SE 7 SE 31N sw 8 5E 31N
SE 8 SE 31N
036 2225 8 sw 10 SE 31N
SE 9 SE 31N
037 2275 0 SE 3 SE 31N sw 3 5£ 31N
SE TO 5E 31N sw 10 SE 31N
NE 9 5E 31N
038 2110 0 SE 11 SE 31N sw 11 5E 31N
Locations of Lakes
Lake Elevation No~ Quarter
number MSL pushups section Section Range Township
NW 14 SE 31N
NE 15 SE 31N sw 15 SE 31N
NW 15 5E 31N sw 10 5E 31N
039 2325 0 NW 3 5E 31N
040 2240 0 sw 21 5E 32N
041 2225 1 NW 21 5E 32N
042 2240 0 NE 21 5E 32N
043 2260 1 NE 21 5E 32N
NW 22 5E 32N
SE 21 5E 32N
NE 21 5E 32N
044 2275 0 sw 15 5E 32N
NW 22 5E 32N
045 2240 0 SE 16
NE 21 5E 32N
046 2275 0 SE 15 SE 32N sw 45 5E 32N
047 2240 7 NW 15 SE 32N
NE 16 SE 32N
048 2425 6 NW 10 5E 32N
049 2350 0 NW 14 5E 32N sw 14 SE 32N
050 2350 0 NW 14 SE 32N
051 2350 0 NW 14 SE 32N
052 2350 0 NW 14 5E 32N
NE 14 SE 32N
053 2350 0 NE 14 SE 32N
054 2350 0 SE 14 SE 32N
055 2350 0 NE 14 SE 32N
SE 14 5E 32N
056 2350 0 NE 14 5E 32N
NW 13 5E 32N
057 2275 0 sw 35 SE 32N
058 2324 0 NE 53 5E 32N
059 2275 32 NE 13 5E 31N
NW 18 5E 31N sw 18 5E 31N
SE 13 5E 31N sw 13 5E 3lN
SE 14 5E 31N
NE 14 5E 31N
NE 13 5E 31N
060 2270 0 sw 5 6E 31N
SE 5 6E 31N
NE 8 6E 31N
SW 8 6E 31N
Locations of Lakes
Lake Elevation No. Quarter
number MSL pushups section Section Range Township
SE 7 6E 31N sw 7 6E 31N
NE 7 6E 31N
NW B 6E 31N
061 2225 3 SW 4 6E 31N
SE 5 6E 31N
062 2225 0 NW 2 6E 31N
063 2325 0 SE 19 6E 32N
064 2375 0 NW 19 6E 32N
NE 24 5E 32N
065 2450 3 sw 18 6E 32N
066 2350 0 NE 1B 6E 32N
NW 18 6E 32N
067 2350 24 sw 7 6E 32N
SE 7 6E 32N sw B 6E 32N
SE 8 6E 32N
filE 17 6E 32N
NW 17 6E 32N
NE 1B 6E 32N
068 2270 15 SE 17 6E 32N sw 16 6E 32N
NW 21 6E 32N
NE 20 6E 32N
069 2275 14 SE 11 6E 32N
070 2325 B NW 12 6E 32N
071 1750 5 SE 24 6E 32N
072 1650 2 NW 31 7E 32N
073 2000 0 sw 29 7E 32N
074 2050 2 NW 29 7E 32N
NE 29 7E 32N
SE 29 7E 32N
075 2050 0 SE 29 7E 32N
NE 32 7E 32N
076 2050 2 sw 28 7E 32N
077 2050 0 SE 29 7E 32N
078 2050 0 SE 29 7E 32N
079 3150 0 SE 23 7E 31N
080 2750 0 SE 6 8E 31N
081 2700 0 SE 6 BE 31N sw 5 BE 31N
082 1850 2 sw 8 BE 31N
083 2525 0 sw 33 BE 32N
NE 33 BE 32N
084 2525 0 NW 3 8E 31N
085 2650 0 sw 2 8E 31N
SE 2 8E 31N
Locations of Lakes
Lake Elevation No. Quarter
number MSL pushups section Section Range Township
086 2650 0 SE 2 BE 31N
087 2650 0 SE 2 BE 31N
OBB 2431 1 SE 7 9E 31N
089 2840 25 SE 25 llE 30N sw 30 llE 30N
NW 31 11E 30N
NE 36 llE 30N
090 2855 2 SE 30 llE 30N
NW 31 llE 30N
091 2B50 0 NW 31 11E 30N
092 2550 1 sw 5 llE 29N
NW 8 llE 29N
093 2550 0 NW 8 llE 29N
NE B 11E 29N
SE 8 llE 29N sw 8 11E 29N
094 2560 0 SE 5 11E 29N
NE 8 llE 29N
095 2550 0 sw 4 llE 29N
096 2550 0 NW 9 11E 29N
097 2550 0 NW 9 llE 29N
098 2550 0 NW 9 11 E 29N sw 9 llE 29N
099 2550 0 SE 8 llE 29N sw . 9 llE 29N
100 2BOO 1 NE 26 10E 30N
101 2800 0 NE 26 1 OE 30N
NW 25 1 OE 3QN
102 2BOO 0 sw 24 lOE 30N
103 2BOO 0 sw 23 3E 30N
NW 26 3£ 30N
when snowmelt was in advanced stages but lake and river ice still remained.
Up river from Gold Creek the bulk of sign of these aquatic species was
found in lakes on plateaus above the river vailey between 2000 feet and
2400 feet MSL Two s ighti ngs of beavers were reported by surveyors
working along the Susitna River between Fog and Devil Creeks, however,
these beavers may have been dispersing 2-year-olds since to our knowledge
no active lodges or bank dens have been sighted on the river, or on the
lower reaches of the feeder streams.
3. 3 -Fox Den Surveys
Ten den sites were located between Devil Creek and ~latana Creek in 1980
(Figure 3). Two of these sites, number 8, Swimming Bear Lake, and
number 9, High Lake, were used for rearing young in 1980. One site,
number 10, Watana Creek, which was discovered in November 1980, showed
signs of use during the preceding summer. No sign of activity was
observed at the remaining 7 sites during the year.
Den sites discovered in the Susitna area are characterized by south-
facing slopes, sandy soil, offering a good view of the surrounding area,
and by being nea.r water, in most cases adjacent to a lake. Further,
dens found were either above or near treeline between 730 meters (2200
feet MSL) and 1066 meters (3200 feet-MSL). Murie (1944) reported that
"Red fox dens in McKinley Park were in the open and in the woods,
on sunny knolls far up the slopes, and on the flats. Most of them
\~ere dug in sandy 1 cam ... 11
•
His findings are similar to ours except that ground and air searches
have thus far failed to produce fox dens in the woods. Allison (1971)
working in Mt. McKinley National Park recorded dens in habitats
similar to the dens we observed. Allison made no mention of woody
plants near dens over 4 feet in height, except alder. Steve Buskirk
{pers. comm.), a Park Ranger for several years in ~4cKinley National
Park, stated that some fox dens did occur in the woods in the Park.
17
. .
~I IT): <:q
-J,
<:t.•
I c}
0
TSUSENA
6 BUTTE (' . 6
b~ ,o
Q
KEY
• Den Locolions
~ Ronges
5 10 MILES
0'--1 _.__, --'----''-'---LT_~__,tp KILOMET.ERS
Figure 3. Locations of fox dens discovered during 1980 and minimum home ranges of 3 radio-collared foxes.
Allison (1971) noted that
11
••• red foxes use homesites only during the small part of each year
when the young are being rai sed 11
•
This is not the case in our study a~ea where fox tracks were often seen
during the winter at or near den sites. In most cases, at least 1
entrance was kept clear of snow and showed evidence of being enter-ed by
a fox throughout the winter.
Fox pups remained at den sites into September on our study site.
Allison (1971) reported that fox families vacated dens by mid-August in
Mt. McKinley National Park. Storm (1972) reported fox families utilized
den sites until late July in the midwest. Storm (1972) found that foxes
in Iowa and Illinois remained together as a family unit into October.
Sheldon (1950) observed that some fox families stayed together until
September and that the latest date of an occupied den was recorded on
July 10, 1947. Sheldon's study area was in central New York. Our
findings in the Susitna area suggest that a period of roughly 1 month
may pass between abandonment of the den site and dispersal of young. A
period of about 3 months passed between abandonment of the den site and
dispersal in Storms study area in Iowa and Illinois.
Present information indicates that foxes in the study area utilize den
sites much later than in other areas of Alaska. The latest date reported
for foxes at dens in Alaska is August 11 (Magoun, pers. COTTITl.).
3.4 -Live Trapping and Radio-collaring
3.4.1 -Red Fox
Five foxes were fitted with radio collars (Table 3): 3 pups from
the Swimming Bear Lake site, 1 pup from the High Lake site, and 1
adult-sized fox from the Wa tana site (Figure 3) .
19
Table 3. Background for captured foxes. Capture locations are shown on Figure 3.
Fox #1 Fox #2 Fox #3 Fox #4 Fox #5 Fox #6
Date 8/10/80 8/l 0/80 8/10/80 9/2/80 9/4/80 ll/l 0/80
Time 5:40 a.m. 5:40 a.m. 5:40 a.m. 9:30 p.m. 7:00 a.m. 9:30 a.m.
location Swimming Swimming Swimming High Lake High Lake Watana
Bear lake Bear lake Bear lake
Weight 3.1 kg 3.3 kg 3.5 kg 6.4 kg 4.3 kg 5 kg
Total length 88.0 em 89.0 em 42.0 em 105 em 101 em
Tail length 32.0 em 34.0 em 35.0 em 39.0 em 39.4 em
Muzzle length 7. 5 em 6.6 em 7.0 em 7.0 em 7.3 em
Nose pad width 1. 9 em 1. 8 em 2.0 em "U 2.3 em 2.2 em
~
Shoulder 33.5 em 33.2 em 36.0 em a. 40.0 em 40.0 em n:J u
Right ear 6.8 em 8.2 em 8.1 em V) 9.0 em 8.3 em Q.l ...,...,
Hind foot 15.2 em 15.5 em 17.0 em 18.0 em 16.5 em
Color phase red red cross red cross red
Co 11 ar no. 526 528 530 527 529
Co 11 ar freq. 164.567 164.615 164.667 164.590 164.641
Ear tag no. 104 105 106 109 110 111
Age class juvenile juvenile juvenile Believed adult juvenile juvenile?
Sex F M M M F
Two pups dispersed from the Swimming Bear Lake site during the
period September 20, 21, 22, 1980. One pup (fox No. SBL2) established
a territory in the vicinity of its den (Figure 3) . Another (fox
No. SBL1) establ.ished a territory in an adjacent drainage 2.4 krn
(1.5 miles) north of its den site {Figure 3). A cross color phase
pup (fox No. SBL3) dispersed out of the area (Figure 3). He was
last seen at 1:40 p.m., 22 September 1980, about 2.4 km (1.5 miles)·
southeast of the den site.
In 1980, the Swimming Bear Lake area.was occupied by a red female
adult and 3 pups, 2 of which were the red color phase and 1 a
cross-color phase. When the den was initially discovered in late
July, an adult cross fox was observed on 2 occasions at the den
site. This fox was believed to be the adult male.
An active den site 2.4 km (1.5 miles) north of High Lake was discovered
in early September 1980 (Figure 3). Upon our arrival, 2 September 1980,
at 1 east 3 separate foxes were seen at the den: 1 red, 1 1 i ght
red, and 1 cross. At 9:30 p.m., 2 September 1980, a red female was
captured {fox No. HL4). She weighed 6. 4 kg ( 14 1 bs.) and escaped
while being measured. This appeared to be an adult female. Pups
and adults were difficult to distinguish due to the large size of
the pups. It also seems likely that there were at least 2 foxes at
this site which had almost identical coloration. Based on observations
at that time, it appeared that 1 red female and 3 pups (1 red, 1
light red, and 1 cross) were occupying the den.
On 4 September 1980 a cross pup weighing 4.3 kg (9.5 lbs.) was
captured about 1.6 km (1 mi1e} east of the den. This animal had
lost its milk canines and the carnassials were erupting (Table 3).
No new tracks or activity at the den were observed on 3 September
or 4 September 1980 and when no fox signs were observed after.
subsequent visits to the site, it was assumed that the den had been
vacated. Sheldon (1950) suggested that dens are abandoned about
the time the pups lose their lacteal dentition.
21
The cross pup (fox No. HL4) fitted with a radio-collar at High Lake
den was located only on 2 occasions after release, despite intense
efforts to relocate it (Figure 3). On 21 September 1980 this fox 1 S
signal was picked up and followed. He was located approximately
1.6 km (1 mile) south of Swimming Bear Lake near a small lake.· Two
pups from the Swimming Bear Lake den were also located in· that same
area on 21 September. On 18 October 1980 the radio signal from
this fox was again received and followed. He was located on a
ridge~ 4200 1 MSL, between Devil Creek and Portage Creek and about
11.2 km (7 miles) north of the High Lake den (Figure 3).
In early November 1980 an abundance of fox sign was noted along
Watana Creek. On 6 November 1980 five steel traps were set in
favorable locations along the creek. Wann weather and the fonnation
of anchor ice in the creek increased the water level. This flooded
all traps within 3 days. Fox tracks around a lake on the plateau
above Watana Creek were spotted and investigated. A red fox was
observed sitting on a den mound. Two traps were set on the frozen
1 ake and on 10 November a red fox (fox No. WCS) weighing 5 kg ( 11
pounds) was captured and fitted with a radio collar. This fox was
accompanied by another red fox of about the same size, possibly a
litter mate. Since the date of capture, this fox has remained in
the area of the Watana den (Figure 3).
Radio-telemetry, snov-1 transects, and observation flights suggest
that some foxes may remain at higher elevations throughout the
year. Searches of the area by project investigators in late
winter and early spring 1980 produced no evidence of foxes along
the Susitna River or the lower elevations along tributaries.
Tracks and other signs of foxes were noted along the banks of the
Susitna River in late fall and early winter 1980. \<linter snow
transect surveys in 1980 produced evidence of utilization of the
shores of the Susitna River in late fall and early winter. This
seasonal movement pattern will be studied closely in the upcoming
year.
22
Ptarmigan and arctic ground squirrels may be principal prey species
(Table 4) of foxes. Ptarmigan and/or their tracks were observed
each time investigators approached areas where foxes had foraged
near or above timberline during winter. During surrmer, ground
squirrels were sighted whenever investigators were nea·r fox den
sites. Ground squirrel remains were found at den sites in the
summer. Murie (1944) states that ground squirrels in McKinley Park
were abundant and much used by foxes. He has little to say relating
to use of ptarmigan because populations of these birds were low in
the park at the time of his studies. Scat analyses and additional
carcass necropsies will provide more concrete information.
The snow transect scheme was designed to provide data which wi 11 ·
allow us to correlate the tracks of a specific species with vegetation
cover, snow depth, and elevation during late fall and early spring.
The transects provide an index to areas intensely utilized by
foxes. Data were also collected from following fox trails on the
ground to gain a finer scale of resolution, especially in the snow
depth and vegetation categories. Snow hardness is measured along
fox trails to assess the effects of snow hardness as well as snow
depth on fox movements.
The void in our fox data base for the snow-free months will be
filled by monitoring transmitter-equipped foxes, scat collection,
observation at den sites, and stream sandbar surveys. All of these
surveys were initiated in 1980 and will be continued in 1981.
Additional data regarding utilization and/or exclusion of/from
stream bank habitat, juvenile dispersal, and food habits will be
forthcoming in 1981.
3.4.2 -Marten and Mink
A total of 4 marten and 2 mink were radio-collared during 1980.
Home range sizes and shapes were obtained for 3 adult male marten.
23
Table 4. SunJnary of necropsies of 9 red fox carcasses obtained from Don Newman and ~1ary Kay McDonald. All of
the foxes were trapped within 20 miles of Adventures Unlimited Lodge, mile 100 Denali Highway.
SPEC. NO. SEX FEMORAL MARROW FAT
475 F pink -red
476 M pink, no yellow
477 pink, no yellow
478 M yellowish pink
479 F pink, not yellow
480 ? pink, not yellow
481 F pinkish yellow
482 F red, gelatinous
483 F pink, some yellow
BODY FAT
not
observable
minimal
thin
moderate
minimal
none
none
none
Ot1ENTAL FAT
moderate
GASTROINTESTINAL CONTENTS
black bird feathers,
unknown fur
empty
salmon bones and flesh,
mouse parts, ungulate fur
caribou fur, flesh and bones
caribou fur, hare fur, bird
(ptarmigan?) feathers, bi-
colored mouse tail
ptarmigan remains
several feather shafts
CQr.1MENTS
probably a
quick kill
probably not
a quick kill
probably a
quick kill
tapeworms
present in gut
skull not
collected
reproductive
track collected,
probably not ·a
quick kill
probably not a
quick k i 11 , 6
placental scars
counted (4+2)
No meaningful home range data were obtained for mink. Background
information for the 6 collared mustelids is presented in Table 5.
Home range and movement data for 4 marten are given in Figure 4.
Daily activity pattern data for 3 adult male marten a.re presented
in Figure 5.
Home range data acquired to date pertain solely to male marten. It
appears that adult male marten have mutually exclusive home ranges
during surrmer, with creeks in some cases forming home range boundaries.
Radio 1 ocati ons depicted are primarily those of daytime resting
sites. The minimum areas of 3 of these marten home ranges (518,
519 and 520) were 4. 74 km 2 (1.83 mi 2 ), 5.44 km 2 (2.10 mi 2) and 4.87
km 2 (1.88 mi 2) respectively. These home range minimum size estimates
are made with the following assumptions·:
1. Creeks and the Susitna River form home range boundaries during
surrmer.
2. Marten home ranges do not extend above treeline during summer.
Movements of marten beyond the home ranges depicted by these
resting locations may be significant and could indicate considerably
larger home range sizes.
Many estimates of North American marten home ranges reported in the
literature (Hawley and Newby 1957, Linsink 1954) are based upon
capture-mark-recapture methods. Archibald (1980) has shown that
home range sizes determined by telemetry are greater than home
range sizes for the same animals determined from trapping grid
methods. Archibald found that telemetry-based horne ranges for 5
marten over 1 year in age (2 males, 3 females) averaged 4.1 km 2 .
Mech and Rogers (1977) found 4 marten (3 males, 1 female) in
Minnesota to have an average home range size of 12.8 km 2 .
The activity data gathered to date (Figure 5) suggest that during
autumn marten are nocturnal, with limited activity occurring
25
Table 5. Background information for radio-call a red mustel ids, Tsusena Creek study area.
Collar Age Wei~ht Capture
Number Species Sex Class (g Date Remarks
519 marten male adult 1440 22 Aug 80 Testes scrotal
23 Aug 80 Released from trap·
25 Sep 80 Released from trap
520 marten male adult 1370 27 Aug 80 Testes scrotal
518 marten male adult 1380 9 Sep 80 Testes receding
1120 25 Nov 80 Transmitter dead, last
heard 12 Nov.; transmitter
replaced.
515 mink male 1 yr. + 780 2 Oct 80 Canine teeth broken.
Collar slipped between
19 Oct. and 30 Oct.
516 marten male ? 1260 2 Nov 80 This animal caught
by a trapper on 28 Nov.
510 mink male juvenile 580 28 Nov 80 Weasel collar attached.
Transmitter failed in
1-2 days.
~
\
o::tl<:t
lc_:Cl
\f';lc:t
FCiirbanks <t ~ C!
0 -.1\o::t
"t~I,J
\
I
KEY _5--i
• No. 516
o No. 518
• No. 519
~ No.520
.....;__ (T) Trap Location
0 2
~LEVATIONS IN FEET
Figure 4. Tracking locations for 4 radio-collared marten.
:3 km
100
90
80 -~ 0 -70
a
IJ.J > 60 a:
lJ.J
(f)
CD 50 0
>-r-40 ->
r-u 30 c:::r
20
28 12 10 17 37 .---.--,.... -35 30 24
r12 rr-r-
~ ~
!9 22
1-r-37 r-
17
1-
-
18 3E
r-r-
~
19 20
1--r-
II -
.f~ 18 }S_
0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0
0 N ~ W W 0 N ~ W 00 0 N
0 0 0 0 0 N N
TIME OF DAY
Figure 5. Daily activity patterns of 3 adult male marten, 24 September -
20 October 1980. Columns reflect the percent of total radio
·eadings that indicated activity. Numbers at the top of
lumns indicate total numbers of readings.
around 1200 hours. In most cases observed marten become active
near sunset and continued to be active throughout the night with
few or no periods of inactivity. Activity usually ceased near
sunrise.
3.5 -Following Fox Trails
Data from fox snow tracking surveys were recorded on standard data
sheets (Table 1). These data will be analyzed during.l981.
3.5 -Food Habits Studies
Scats and gastrointestinal tracts of mustelids were dried and stored.
None were analyzed during. 1980. Fox scats and remains of food items -from den sites were collected and stored. Analyses wi 11 be conducted
during 1981. Gastrointestinal contents from 9 red fox carcasses were
identified (Table 4).
3.7 -Transects
Analyses of aerial transect data were not completed in 1980.
3.8 -Downstream Furbearer Surveys
Use of the Susitna River by aquatic furbearers, especially beavers,
increases progressively downstream from Devil Canyon as the river leaves
the foothills of the Alaska Range and flows south to the confluence of
the Kashwitna River. Increasing abundance of aquatic forbearers is best
illustrated by sign of beavers (Table 6). In Section I, above the
confluence with the Talkeetna and Chulitna Rivers, beaver sign is limited
to occasional foraging sites and lodges along protected banks of the
river, sloughs and tributaries. In Section II foraging sign is common
along sloughs, deltas of tributaries and along stable banks of the
Susitna River. Additional lodges and possibly bank dens not observed by
the survey team probably exist away from the main channel of the river.
Sign of beavers is in sight almost continuously along Section III. The
29
Table 6. Occurrence of Beaver signs along 3 sections of the lower
Susitna River: Section I = Devil Canyon to confluence with
Talkeetna and Chulitna Rivers, Section II = confluence with
Talkeetna and Chulitna Rivers to confluence with Montana
River
Section
Section
Section
Section·
Creek, Section III = confluence with Montana Creek to Cook Inlet.
Numbers in parentheses are adjustments to realistically reflect
signs present in the Mature and Old River surveys. Signs were
multiplied by a correction factor of 2 in the Mature River
Section and a factor of 3 in the Old River Section. The
increasing width and braiding of the river penni tted the team
to see approximately half the signs in Section II
. and only a fourth to a third. in Section III.
Miles Number
Beaver Sign
Cuttings Number Houses
Surveyed Cuttings per Mile Houses per Mile
I 39 12 .31 2 .05
II 19 7 .37 (. 74) 2 . 11 ( .22)
III 16 16 1. 00 ( 3. 00) 4 .25 ( . 75)
Entire Survey 74 35 .47 8 .11
numerous islands and sloughs provide ideal habitats for foraging, caching
food and building lodges, and only a portion of the sign was visible
from the riverboat. An attempt to correct for increasing width and
braiding of the river and limited visibility was made in Table 6.
Results of this survey agree with findings of Boyce (1974) and Hakala
(1952) who reported beavers in Alaska favor lakes or slow flowing streams
bordered by subclimax stages of shrub and mixed coniferous and deciduous
forests. This description fits Section III of the Susitna River. Large
rivers with narrow valleys and high velocity flows such as Section I of
the Susitna River, are generally sparsely populated by beavers (Retzer
1955).
Other mammals observed in the downstream surveys included a moose calf
in the Section I and 2 black bears in the Section II. Tracks of bears
were common in· a 11 sections of the river and 2 sets of wo 1 f tracks were
observed in Section III.
3.9 -Otter and Mink Surveys
Results of the otter and mink surveys made during November 1980 are
presented in Table 7. An unusually high incidence of otter sign was
noted along the Susitna River during November. These surveys will be
repeated during November 1981 to determine if otters again concentrate
along the river at this time of year.
3.10-Other Furbearers
Limited data were obtained for coyotes, lynx, short~tailed weasels and
least weasels. Coyotes occur in the study area, however, they are
uncorrnnon and restricted to local family groups. Mr. Harold Larson, an
agent for the Alaska Railroad at Gold Creek reported trapping a male
coyote near Gold Creek during the 1979-1980 trapping season. Mr. Larson
noted tracks he believed to have been made by coyotes along the Susitna
31
Table 7. Results of otter and mink surveys, Susitna River, 10 November -
12 November 1980. Number of tracks of each species observed
at north and south sides of 37 river check points (Figure 2).
Checkpoint North South
Numbers Otters Mink Otters Mink
01 3 0 0 0
02 0 2 0 0
03 0 0 0 0
04 0 0 3 1
OS 0 0 2 0
06 0 0 0 0
07 0 1 0 1
08 0 0 0 2
09 0 0 1 0
10 0 0 0 2
11 - 4 1 0 1
12 3 1 0 0
13 0 0 0 1
14 2 0 3 1
15 0 0 4 0
16 3 1 0 2
17 0 3 0 4
18 0 0 0 2
19 0 0 1 2
20 2 0 1 0
21 1 1 0 0
22 0 0 0 0
23 2 1 0 2
24 0 0 0 0
25 0 0 0 0
26 0 0 0 0
27 0 0 4 0
28 0 0 4 0
29 0 0 0 2
30 0 0 0 0
31 0 0 0 0
32 0 0 0 3
33 0 2 0 3
34 0 1 0 2
35 0 1 2 3
36 0 0 2 2
37 0 1 0 2
River near Gold Creek throughout the winter of 1979-1980. Mr. Ed Powell
of Stephan Lake Lodge indicated that on 12 September 1980 he heard a
coyote howling a short distance southwest of the lodge. On 6 October
1980 helicopter pilot Richard Harkness informed Buskirk that on three
occasions during the preceding 4 weeks he observed a coyote in the
vicinity of 62°47'30 11 N .. , 149°10'00 11 \tJ. On 13 October 1980 Buskirk flew
to this location with Harkness, but did not observe the animal which
Harkness described. No other reports or observations of coyotes in the
study area were obtained.
No direct evidence of lynx in the study area has been obtained. No lynx
have been reported taken in the impoundment zones by trappers during the
past two trapping seasons, and no observations of lynx by other project
personnel have come to our attention. On 19 November 1980 Hobgood and
Buskirk observed from the air a set of tracks which may have been made
by a lynx. These were observed on the Susitna River beach on the north
side of the river on aerial transect A-13. The observers were unable to
land near the tracks to confirm the identification. In a December 1979
telephone conversation Harley McMahan, a Glenallen trapper, told Buskirk
that he and his father had taken lynx in the canyon country of the
Susitna River in the past. McMahan stated that lynx were fairly numerous
in the winter of 1976-77, and were found primarily in forests along the
river.
Short-tailed weasels. Short-tailed weasels are common and locally
abundant in the study area. Their tracks have been observed in a variety
of habitat types from the elevation of the Susitna River up to approximately
2600 feet above sea level. Short-tailed weasels or their tracks have
been observed from near the mouth of Portage Creek to the Tyone River.
Trappers on upper Tsusena Creek, in the Fog Lakes area and at Stephan
Lake take them deliberately or incidentally while trapping other species.
Least weasel. Least weasels occur in the study area, however, their
distribution, relative numbers and habitat preferences are poorly understood
at this time. Several sets of tracks were observed on lower Watana
Creek in March 1980 which we felt were definitely made by least weasels.
33
4 -IMPACT ASSESSMENT
4.1 -Construction Impacts
We consider construction impacts to be those attributable to:
(a) Excavation of borrow sites.
(b} Clearcutting and burning of woody vegetation in impoundment zones.
(c) Dam construction.
(d) Physical disturbance associated with road construction.
(e) Physical di.sturbance associated with transmission system construction.
(f) Other human activities such as transportation of personnel and
equipme·nt associated with the construction phase.
It is difficult to predict construction impacts of the project in l_ight
of the uncertainty of: 1) the number, location, and size of dams to be
constructed, 2) the routes of access corridors, 3) a possible railroad,
4) diversion tunnel lengths and configurations, 5) borrow pits to be
used and the extent of that use, and 6) the timing and duration of th~
actual construction. Each combination of these variables presents us
with a unique set of conditions to assess and impact will vary in degree
for each combination. In addition, published accounts of impact prediction
and the demonstrated accuracy of such predictions are limited for furbearers
in northern areas. Generally, where habitat. is lost or degraded, furbearer
numbers will decline. In our preliminary assessments of project impacts
we have relied upon our present understanding of the distribution,
habitat requirements and life strategies of furbearers in the study
area.
34
(a) Excavation of borrow sites
Borrow site excavation will affect furbearers primarily due to loss of
denning and foraging habitats, although some habitat restoration may be
possible over several decades. Species most likely to be affected by
borrow pit excavation (based upon proposed borrow sites) appear to be
marten and fox. The proposed borrow site on upper Tsusena Creek could
have negative local effects on foxes, mink, marten, otters and short-
tailed weasels due to the relatively large area of land involved.
(b) Clearcutting of woody vegetation in impoundment zone
In general, habitat will be lost and furbearers eliminated in the impoundment
zones, ·and at dam sites. The species most severely impacted by clearing
forests will probably be those which rely heavily upon forest, riparian
and riverine habitats -marten, lynx, mink and otter.
(c) Dam construction
The physical structures of the dams will usurp several square miles of
land and this habitat will be lost.
(d) Physical disturbance of road construction
The physical disturbance and habitat loss from road (or railroad bed)
construction would be relatively minor due to the small amount of 1 and
involved. The most serious impacts from road construction will arise
from improved human access and collisions of wildlife with vehicles.
These impacts are discussed under section 4.2.
(e) Physical disturbance of transmission system construction.
We assume that transmission system construction will involve placement
of transmission towers between the dam sites and the Parks Highway. We
also assume that helicopter construction techniques will be employed and
35
that roads will not be built. If roads are built during construction of
transmission systems, our comments under 4.1(d) and 4.2(d) apply.
Impacts to furbearers from helicopter-assisted construction would consist
chiefly of behavioral disturbance and would be relatively minor.
Furbearer habitat along the selected transmission route to the intertie as
we 11 as the se 1 ected routes from Wi 11 ow to Anchorage and Hea 1 y to
Fairbanks as necessary, will be assessed during 1981.
(f) Other human activities associated with the construction phase.
Other human activities resulting from the construction phase include
hunting and trapping by construction personnel, disposal of construction
camp garbage and feeding of furbearers, primarily foxes and marten, by
construction personnel. These impacts may be relatively light or severe,
depending upon education programs and regulatory measures taken. This
type of impact is subject to mitigation and it is discussed in section
5.
4.2 -Operation Impacts
(a) Downstream alterations in flow regime and water quality.
Projected changes in the flow rates of the Susitna River downstream from
the Devil Canyon impoundment could result in marked changes in the
quantity and quality of aquatic furbearer habitat. This was the case in
the downstream portion of the Peace River following construction of the
W.A.C. Bennett Dam where an extensive marsh on the Peace~Athabaska Delta
became dry and furbearers numbers were reduced (Baxter and Glaude
1980): Reduced circannual water level fluctuations could conceivably
create a water flow regime more favorable to muskrats and beavers. On
the other hand, elimination of peak flows at breakup or at other times
may have the effect of drying up wetlands and reducing the amount of
subclimax, riparian vegetation along the river's edge.
36
Aquatic and semiaquatic furbearers (beaver, muskrat, otter and mink) are
not knovm to select habitats on the basis of water turbidity. It seems
unlikely that these species would be affected favorably by a reduction
in water turbidity. -Altered fish populations may have major (positive
or negative) downstream effects upon otters and mink. Predictions of
such effects must await projections of changes in downstream fish populations.
(b) Watana Dam and Reservoir.
The flooding of the Watana Reservoir will eliminate terrestrial furbearer
habitat and create some habitat for aquatic forbearers. The quantity
and quality of habitats created and lost will depend upon the maximum
pool elevation, stability of pool level, ice characteristics, draw-down
zone vegetation, reservoir fish and invertebrate populations. Assuming
that annual f1uctuations in water level will be 30-50 m (90-150 ft.)
vertically, and that water level will rise during summer, peak in autumn,
and decline during winter, there will be a large, unvegetated draw-down
zone. This draw-down zone and the aquatic habitat created will be of
limited value to otters, mink, muskrats, and beavers.
The flooding of the Watana Reservoir will cause loss of terrestrial
furbearer habitat. The species most severely impacted from this habitat
loss will be marten due to their high dependence upon forested habitats
along the Susitna River and lower elevations along tributaries. Foxes
are known to utilize riparian zones along the Susitna River and its
tributaries during summer and autumn, but their degree of dependency
upon these habitats has not yet been determined.
(c) Devil Canyon Dam and Reservoir.
The flooding of the Devil Canyon Reservoir will eliminate terrestrial
furbearer habitat and create,some aquatic furbearer habitat. The degree
of this habitat change will depend upon the pool elevation and stability
of the pool.
37
The aquatic habitat created by this reservoir may be of cons·iderable
value to otters, mink, and possibly to beavers and muskrats. Assuming
that water level fluctuations are less than 2m (6 ft.) vertically, that
these fluctuations have a daily cyclic nature, that vegetation is
permitted to grow within 19m (30ft.) of the reservoir 1 s shore and that
suitable populations of prey fish are found in the reservoir we predict
that otters and mink will be favorably affected by the habitat created.
Beavers and muskrats utilize the area within the Devil Canyon impoundment
zone very little at this time and may be favorably affected by the
aquatic habitat created. However, Murray (1961) indicated that the rise
and fall from the nonnal water level should be no more than .6 meters (2
feet) for beavers to utilize an area. We are unable to predict how
beavers and muskrats will be impacted until additional data are available
about water level fluctuations, shoreline soils and shoreline vegetation.
(d) Access roads or railroads.
After the construction phase is completed, public use of access roads
may have marked impacts upon furbearers. The public use impacts of
roads would consist primarily of increased harvest and human harassment
of furbe-arers in the study area. Roads would provide convenient access
to areas which are now and have historically been remote. The severity
of this_ impact would depend upon regulatory measures imposed. Since
this impact is subject to mitigation through management measures, it is
discussed in section 5. Vehicle-wildlife collisions would be another
source of impacts to furbearers. The severity of this impact is difficult
to predict because of the paucity of relevant published information. ~~e
believe that losses of furbearers resulting from vehicle collisions will
be relatively low.
Once constructed, railroads would have minimal impacts upon furbearers.
Railroads do not provide the ease of access which roads provide and we
predict that a railroad could be operated without significantly impacting
furbearers along its route. There may be little need for regulatory
mitigative measures.
38
(e) Borrow sites.
The primary negative effect of borrow site development is removal~ which
affects utilization of borrow sites by furbearers and their prey. Left
unvegetated, borrow sites would have little value to furbearers. Vegetation
restoration measures would determine the suitability of restored habitats
for various furbearers. The creation of grasslands and shrub vegetation
may be attractive to small mammals and birds and thus provide foraging
habitat for foxes, especially if vegetative heterogeneity is maintained.
We believe it extremely unlikely that destroyed marten habitat could be
regenerated in less than 75 years.
(f) Transmission facilities.
We assume that the operation of transmission facilities consists chiefly
of occasional maintenance activities at transmission towers between the
dam sites and the Parks Highway. We also assume that access for such
maintenance work would be by means of helicopter. If road access is
provided, our comments under 4.2(d) apply. Impacts upon furbearers from
these occassional maintenance activities would probably be negligible.
Operational impacts of transmission facilities from Willow to Anchorage
and Healy to Fairbanks have not yet been assessed.
39
5 -~-1ITIGATION
(a) Dam construction and excavation of borrow. sites.
Habitat loss and disturbance due to construction activities can be
mitigated by minimizing the size of construction zones and selecting and
utilizing borrow sites as close as possible to the dams. Road construction
may be minimized in the same manner.
If dams are engineered to provide access for spawning salmon into the
system upstream from Devil Canyon, negative impacts to aquatic and
terrestrial furbearers would be curtailed.
Pending further assessment of this aspect of potential impacts, we are
optimistic that the introduction of spawning salmon into the upper river
would positively impact all furbearer species present, including beaver
and muskrat due to increased nutrients supplied to the system.
(b) Other human activities associated with the construction phase.
·Trapping carried on by project personnel could resu1t in severe local
depletion of furbearers. Impacts upon furbearers from trapping and
hunting by construction personnel may be mitigated by regulatory measures.
Habituation of furbearers, particularly red foxes and marten, to human
food sources and garbage may be mitigated. Garbage generated during the
construction phase can be disposed of in such a way that it is never
avai 1 able to foxes and marten. · This may be accompli shed through fencing,
land filling, incineration, transporting garbage out of the area, or a
combination of these methods. Feeding of foxes by construction personnel
may be minimized through education and regulations with strict enforcement.
40
(c) Physical disturbance of transmission system construction.
Physical disturbance of transmission systems construction may be mitigated
by the use of helicopter construction techniques rather than techniques
which require surface access.
(d) Downstream alterations in flow regime and water quality.
Major tributaries of the Susitna River (Chulitna, Talkeetna and Yentna)
may dampen the effects of the Devil Canyon and Watana impoundments
significantly below the town of Talkeetna. Between Devil Canyon and
Talkeetna a critical factor for beavers and muskrats may be maintenance
of stable water flow during spring and winter so that lodges, food
caches, and bank dens can be maintained.
(e) Watana Reservoir pool elevation fluctuations.
Adverse impacts upon otters, mink, beavers and muskrats due to water
level fluctuations could be mitigated by minimizing those fluctuations.
(f) Access road operation.
Adverse impacts predicted from the operation of access roads could be
mitigated through regulatory measures to restrict public access to the
roads and/or manage hunting and trapping activities in the vicinity of
the road.
41
6 -REFERENCES
Allison, L. ~1. 1971. Activity and behavior of red foxes i·n Central
Alaska. M.S. Thesis. Univ. of Toronto. 76 p.
Archibald, W. R. 1980. Marten progress report no. 2. Yukon Wildlife
Branch, unpublished report. 15 p.
Arctic Environmental Information and Data Center. 1980. An assessment
of environmental effects of construction and operation of the
proposed Terror Lake Hydroelectric Facility, Kodiak, Alaska.
University of Alaska, Anchorage. 3 volumes.
Baxter, R. M. and P. Glaude. 1980. Environmental effects of dams and
impoundments in Canada: Experience and prospects. Canadian Bulletin
of Fisheries and Aquatic Sciences. Ottawa. Bulletin 205. 33 p.
Boyce, M. S. 1974. Beaver population ecology in interior Alaska. M.S.
thesis. Univ. of Alaska, Fairbanks. 161 p.
Hakala, J. B. 1952. The life history and general ecology of the beaver
(Castor canadensis Kuhl) in interior Alaska. M.S. thesis. Univ.
of Alaska, Fairbanks. 181 p.
Hawley, V. D. and F. E. Newby. 1957. Marten home ranges and population
fluctuations. J. Mamm. 38{2):174-184.
Konkel, G. (Editor). 1980. Terrestrial Habitat Evaluation Criteria
Handbook-Alaska. U.S. Fish and ~lildlife Service. Anchorage, AK.
596 p.
Lensink, C. J. 1954. The home range of marten (Martes americana actuosa
Osgood) and its significance in management. U.S. Fish and Wildlife
Service, unpublished report.
42
Leopold, A. S. and J. W. Leonard. 1966. Effects of the proposed Rampart
Dam on wi1d1ife and fisheries. North American vJildlife Conference.
31:454-459.
Mech~ L. D. and L. L. Rogers. 1977. Status, distribution and movements
of martens in northeastern Minnesota. U.S.D.A. Forest Service,
North Central Forest Experiment Station~ Research Paper NC-143.
12 p.
Murie, A. 1944. The wolves of Mount McKinley National Park Fauna
Series No. 5. U.S. Govt. Printing Office No. 5. Washington. 238
p.
Murray, D. F. 1961. Some factors affecting the production and harvest
of beaver in the Upper Tanana River, Alaska. M.S. thesis. Univ.
of Alaska, Fairbanks. 103 p.
Retzer, J. L. 1955. Physical environmental effects on beavers in the
Colorado Rockies. Proc. 35th Ann. Conf. W. Assn. State Game and
Fish Corrm. 277-287.
Sheldon, W. G. 1950. Denning habits and home range of red foxes in New
York state. J. Wildl. Mgmt. 14(1):33-42.
Spurr, S. H. (Project Director). 1966. Rampart dam and the economic
development of Alaska. Volume 1, summary report. School of Natural
Resources, Univ. of Michigan, Ann Arbor. 52 p.
Storm, G. L. 1972. Population dynamics of red foxes in North Central
United States. Ph.D. Dissertation. Univ. of Minnesota, Minneapolis.
185 p.
43
7 -AUTHORITIES CONTACTED
Ralph Archibald, Biologist, Yukon Wildlife Branch, Whitehorse, Yukon
Territory -Presently conducting marten studies in the Yukon.
Provided information about marten habitat preferences.
Joan Foote, Biologist, Institute of Northern Forestry, Fairbanks.
Contacted regarding habitat sampling procedures.
David Johnson, Biologist, Alaska Department of Fish & Game, Delta Junction,
Alaska.
-Provided information about furbearer harvests in interior Alaska.
Gregory Konkel, Habitat Evaluation Coordinator, U.S. Fish and Wildlife
Service.
-Discussed possibility of using HEP in assessment studies.
Ron Long, Trapper, Fairbanks, Alaska.
A local fox trapper with extensive knowledge of furbearers. Discussed
historical furbearer population changes.
Harold Larson, Trapper and agent for the Alaska Railroad at Gold Creek. -
Provided information about coyotes and other furbearers near Gold
Creek.
Robert Larson, Biologist, Alaska Department of Fish and Game, Delta
Junction~ Alaska.
-Provided information about furbearer harvest in interior Alaska.
Herbert Melchior, Furbearer Biologist, Alaska Department of Fish & Game.
-Discussed furbearer harvests and management plans.
John Morrison, Supervisor of Biological Services Program, U.S. Fish and
Wildlife Service.
-Discussed possibility of using USFWS data bases to aid in assessing
impacts of development upon wildlife in Alaska.
Don Newman and Mary Kay McDonald, Trappers, Denali Highway, Alaska.
Provided furbearer carcasses and local trapping information.
Leroy Shank, Trapper, Fairbanks, Alaska. -Local marten trapper,
provided historical information about furbearers.
Roger Smith, Trapper, Tsusena Creek, Alaska. -Local trapper, discussed
trapping in the area and arranged for collection of carcasses.
44
Dr. Vic VanBallenberghe, Wildlife Biologist, Institute of Northern
Forestry, Fairbanks, Alaska. -Fonner furbearer biologist \'t'ith the
Alaska Department of Fish andGame. Provided infonnation on furbearers
in 'the Susitna Basin and sampling and field techniques.
Glen Wingkte, Trapper, Kenai, Alaska. -Traps between Gold Creek and
the Devi1 1 s Canyon dam site, provided information ab~ut furbearers
trapped.
Bill Zielinski and Wayne Spencer, Biologists, Sagehen Creek Field
Station, Truckee, California. -Conferred with these biologists
about marten research they are conducting in California.
Mr. Lester E. Eberhardt, Terrestrial Ecology Section, Battel1e Pacific
Northwest Laboratories, Battelle Boulevard, Richland, WA 99352 -
Provided techniques for radio collaring mink and weasels .
. Mr. Al Sargeant, Northern Prairie Wildlife Research Center,
P.O. Box 1747, Jamestown, NO 58401 -Conferred radio collaring mink
and weasels.
Carol Resnick, Tsusena Creek, Alaska. -Provided information on furbearer
occurrence in the study area, furbearer carcasses.
45