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IN
ALASKA DEPARTMENT OF FISH
JUNEAU, ALASKA
STATE OF ALASKA
Bill Sheffield, Governor
DEPARTMENT OF FISH AND GAME
Don W. Collinsworth, Commissioner
DIVISION OF GAME
w. Lewis Pamplin, Jr., Director
Steven R. Peterson, Research Chief
DISTRIBUTION AND MOVEMENTS OF CARIBOU
RELATION TO THE KUPARUK DEVELOPMENT AREA
By
Walter T. Smith,
Raymond D. Cameron,
and
Kenneth R. Whitten
Progress Report
Federal Aid in Wildlife Restoration
Project w-22-2, Job 3.30R
Persons intending to cite this material should obtain prior
Qe l''!li s..s.i o n from the author(s) and/or the Alaska Department of
Ql
7 3 7
. USl
S56
1982
~ Game. Because most reports deal with preliminary
of continuing studies, conclusions are tentative and
· identified as such. Due credit would be appreciated •
(Printed June 1984)
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PROGRESS REPORT
State: Alaska
Cooperator: None
Project No.: W-22-2 Project Title: Big Game Investigations
Job No.: 3. 30R
Period Covered:
Job Title: Distribution and
Movements of Caribou in
Relation to the Kuparuk
Development Area
* 1 January 1982 through 31 December 1982
SUMMARY
Results of calving surveys in the Kuparuk Development Area (KDA)
indicated good initial calf production. However, calving acti-
vity in the KDA was relatively low, as in previous years with
late snowmelt. The calving concentration area north of the West
Sak Road (WSR) appeared to be split into 2 sections, 1 either
side of the Milne Point Road.
In 1982, fewer total caribou (Rangifer tarandus granti) were
observed during surveys along the WSR than in 1981, even though
more surveys were conducted. Very few calves were observed from
the WSR during the calving period. Calf representation along the
WSR has declined over the past 5 years, and cow/calf numbers have
been lowest in those segments with highest construction activity.
Survey observations along the Oliktok Road indicated that most
parturient cows moved into the calving concentration area from
the west, and not across the WSR.
The Kuparuk River remained an important caribou movement corri-
dor. However, increasing traffic and development along the WSR
have apparently diverted most movements into and out of the KDA
to the west of CPF-1, resulting in a circular movement pattern
between the coast and the WSR, similar to the pattern seen in
1981.
Key words: caribou, disturbance, oil field, pipelines, traffic.
* . Fund1ng by ARCO contract 1 January 1982 through 30 June 1982.
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CONTENTS
Summary. . . . . . . . . . . . . . . . . . . . ., . . . . . . . i
Background . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Results and Discussion . • . • • • • • • . • • • . . . . • . . 3
Regional Distribution of Calving Caribou. • . . . . . • . 3
Distribution of Caribou Along the West Sak Road . • . . • 4
Insect-induced Movements. • • . . . • • . • . . . • • . . 5
Literature Cited • • • . • . . • • • • . . . . • • . • • . • • 6
Figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Appendix A. Abstract: Distribution of Caribou Calving
in Relation to the Prudhoe Bay Oil Field • • • . . . •
Appendix B. Abstract: Factors Affecting Pipeline
Crossing Success of Caribou. • • • • • . . • . . • . •
Appendix c. Abstract: Reactions of Caribou to an
Above-Ground Pipeline on the Arctic Coastal Plain
·15
. 16
of Alas·ka. . . . . . . . . . . . . . . . . . . . . . . . . . 17
BACKGROUND
The Kuparuk Development Area (KDA) is located immediately west of
the main Prudhoe Bay oil field. The KDA is an active calving
area and an important component of caribou (Rangifer tarandus
granti) summer range. Detailed knowledge of regional caribou
distribution and movements will assist in the design, placement,
and construction of facilities that would accommodate caribou,
hopefully within established geotechnical constraints. It will
also provide an opportunity to identify and quantify the sources
of local disturbance and the reactions of caribou to these
stimuli. Finally, in conjunction with continued monitoring of
the Central Arctic Herd (CAH) status, results of the present
program will provide an opportunity to document any· effects of
oil field development on herd distribution and productivity.
This report summarizes results of continued surveys of the CAH
calving grounds within the KDA and along the West Sak Road (WSR)
during 1982.
In 1982, the WSR survey program was expanded to include portions
of the precalving (13-26 May) and calving (1-18 Jun) periods in
the KDA. In addition, surveys were conducted along the newly
constructed Oliktok Road during the calving period to monitor the
movements of parturient cows into calving areas north of the WSR.
Three manuscripts were developed from data obtained in the
Kuparuk area. Appendices A and B are abstracts of papers pre-
sented at the 1st North American Caribou Workshop held in con-
junction with the 34th Alaska Science Conference (Whitehorse, Sep
1
1983). These deal with densities of calving caribou in and near
the Prudhoe Bay oil field and factors affecting pipeline crossing
success of caribou, respectively1 both have been submitted for
publication in the Workshop Proceedings. Appendix C is an ab-
stract of a paper describing the responses of large groups of
caribou to elevated pipelines in the KDA1 the manuscript has been
submitted to Arctic.
OBJECTIVES
To describe annual variations in the distribution of CAH caribou
on their calving grounds, with special reference to calving acti-
vity in the vicinity of the KDA. ·
To determine between-year differences in the distribution, move-
ments, and sex/age composition of caribou within or near the KDA
during summer.
To determine the locations of road and/or pipeline crossings by
caribou.
To characterize the responses of caribou to local structures and
disturbance.
PROCEDURES
The distribution of calving caribou in the Kuparuk region was
determined on 11-12 June. We sampled caribou along 12 north-
south transects spaced at 3. 2 km intervals and extending 40 km
inland from the coast (Fig. 1). This area had been surveyed
annually between 1978 and 1981 during the same period, although
in previous years we were able to extend coverage both east and
west within the coastal plain (Cameron and Whitten 1979, 19801
Cameron et al. 1981, 1983).
All transects were flown by Bell 206B helicopter, with the pilot
and front-seat observer searching primarily in the direction of
flight and 2 rear-seat observers searching to either side of the
aircraft. USGS 1:63,360 maps were used for navigation and for
recording locations of caribou groups1 all groups within 1.6 km
of each transect were used in the transect data analysis. Air-
speeds of 110-130 km/hr and altitudes of 30-50 m were maintained
until a group of caribou was sighted. Composition was ascer-
tained by making a lower, slower pass or by hovering briefly at a
distance of 50-300 m and using binoculars. Individuals were
classified on the basis of genitalia, body size, and/or antler
development as bulls, cows, calves, or yearlings.
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The WSR
(Cameron
separate
5 August
tively) .
conducted
(Fig. 2).
(Fig. 2) was surveyed systematically by light· truck
and Whitten 1979), generally twice daily, during 3
phases of study: 13-26 May, 1-18 June, and 1 July-
(precalving, calving, and midsummer periods, respec-
Between 1 and 18 June, an additional 13 surveys were
along the Oliktok Road between CPF-1 and Oliktok Point
For midsummer surveys, the level of insect harassment was esti-
mated subjectively by direct observation as none, light, moder-
ate, or severe. In addition,. mean 4-hour insect levels were cal-
culated using hourly weather reports for Deadhorse airport (ob-
tained from the Arctic Environmental Information and Data Center,
University of Alaska, Anchorage) and the weather/insect activity
relationship of White et al. (1975). Caribou survey data ob-
tained along the WSR (including location, observation distance,
group composition, direction of movement, road/pipeline cross-
ings, and insect levels) were entered in a computer file (Honey-
well Model 20, University of Alaska, Fairbanks).
RESULTS AND DISCUSSION
Regional Distribution of Calving Caribou
In 1982, breakup_ was unusually late, and in mid-June most of the
coastal plain was still covered by snow, ice, and/or meltwater.
As in previous vears of late snowmelt, much calvino occurred
s.outh of the immediate coastal zone. Eight of 15 col-lared cows
relocated in June calved more than 50 km inland, and 1 calved
nearly 160 km south of the coast (Cameron et al. 1984). No cari-
bou were observed in the Canning River delta during reconnais-
sance overflights. In past years, calving activity has been con-
centrated in this area (Cameron et al. 1983); in 1982, however,
the delta was almost completely covered with aufeis and melt-
water.
Within the KDA, 1,103 caribou were observed during helicopter
surveys. As in all previous years of survey, caribou within this
area were distributed mainly toward the coast. Initial calf pro-
duction was relatively low (70 calves/100 cows; Table 1). How-
ever, some calves were born unusually late and, consequently,
final calf production was considerably higher (ca. 80 calves/
100 cows; J. Dau, pers. commun.).
Cows and calves appeared to avoid the WSR during the calving per-
iod. No newborn calves were observed within 4 km of the road.
As in previous years, the density of calving caribou was particu-
larly high in the area between the WSR and Oliktok Point. A
major difference, however, was that this calving concentration
J
area (Fig. 2) appeareo to be split into 2 parts by a strip of low
caribou. density corresponding roughly to the new Milne Point
Road. Density east of the road and in the area as a whole was
low compared to previous years' estimates, but density west of
the road area was quite high (Table 2).
Distribution of Caribou Along the West Sak Road
During the precalving period in 1982, 17.5% of the 412 caribou
seen from the WSR were calves born the previous year (Table 3).
This is in good agreement with an estimate of 17% yearlings (ex-
cluding calves born in 1982) obtained during helicopter surveys
on 11 June (derived from data in Table 1), indicating that year-
ling numbers along the WSR were representative of caribou in the
general region.
In contrast, newborn calves composed only 1.6% of the 310 caribou
seen from the WSR during the calving period (Table 3), substan-
tially lower than a corresponding estimate of 34% calves obtained
by aerial survey (Table 1). This difference is consistent with
the aerial survey observation that no calves were present within
4 km of the WSR on 11-12 June (see above}. Thus, the combined
data indicate that cows with neonatal calves were avoiding the
road/pipeline-corridor.
Additional surveys conducted along the Oliktok Road during the
calving period afforded the opportunity to observe movements of
caribou into the Milne Point calving area. During 13 surveys
hc+taTOOT\ 1· .Tnno ;:,nrl 1Q .Tnno 1 n./LQ l"';:>'r;hl"\11 ta70'ro 1"\hC!O'rnorl ;:~11"\nn-___ ,, __ ...... ..-__ ..,..,_ ............. _ ---__ ...... _, ...,1"'-.., ____ ...... ,.._, __ ,.,.._...__ -----v--.......... _ ...... ;:,
this 26-km road, yielding a sighting rate of 3. 2 caribou/km/
survey. In contrast, data from 22 surveys along the WSR during
the same period yielded only 0.4 caribou/km/survey, or an 8-fold
difference. A mean of 13.6% calves were present among caribou
observed from the Oliktok Road, and 10 groups (33 caribou) were
observed crossing the Oliktok Road, compared with respective
values of 1.6% calves (Table 3) and 1 crossing (4 caribou) for
the WSR transect. These data indicate that most caribou moved
into calving areas north of the WSR from the west and not from
the south, across the WSR. It is unknown if this is a "tradi-
tional" movement zone or an alternate access route used to avoid
the Kuparuk Pipeline corridor.
A total of 8,801 caribou were observed along the WSR during the
summer period, of which 16% were calves. No corresponding
regional data are available for summer 1982. However, initial
production in 1982 was high as in previous years. Assuming early
calf survival was within the "normal" range and that bull and
yearling representation was similar to that noted in past years,
the regional calf proportion would have been approximately 25% in
midsummer.
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It is noteworthy that between 1978 and 1980, the percentages of
calves among caribou observed along the WSR and the corresponding
regional calf percentages, as determined by aerial surveys, were
similar (Cameron et al. 1983). In 1981, however, the local calf
percentage was substantially lower than regional estimates
(Cameron et al. 1983). It appears that this trend continued in
1982.
The distribution of caribou a;nd the mean calf percentage among
4 km segments of the WSR are depicted in Fig. 3. During pre-
calving and calving, most caribou were located in the middle seg-
ments of the road, away from the major nodes of activity at the
Kuparuk River and CPF-1 areas. Groups were often sighted repeat-
edly in the same locations, and only 1 crossing of the WSR was
noted during both periods combined.
Midsummer distribution of caribou along the WSR was characterized
by peaks at the 0-4 1 16-20, and 28-32 road segments. Since 1978,
relative numbers of caribou have been consistently high in the
0-4 km segment of the WSR, which includes the Kuparuk floodplain.
This pattern was particularly pronounced in 1982 when one-third
of all caribou were seen here. The proportion of caribou ob-
served west of km 24 on the WSR decreased markedly from 42% in
1981 to 18% in 1982. We attribute this decrease to the higher
levels of construction activity and traffic near CPF-1 and in
newly developed areas to the west. During winter 1981-82, Mine
Site C (at CPF-1) was opened to provide gravel for CPF-2 and
associated road and drill pads, and there was extensive local
gravel hauling during all survey periods in 1982. The peak at
16-20 km is attributed to the sighting of 1 large group of tran.,.
sient caribou (Appendix C) and does not necessarily indicate the
existence of a node of occupancy.
Calf representation among caribou observed within various seg-
ments of the WSR did not correspond to the overall pattern of
caribou distribution (Fig. 3). In fact, midsummer data indicate
an inverse relationship at the east and west ends of the road,
near the major nodes of construction activity. From 1978 through
1981, calf percentages near CPF-1 were approximately representa-
tive of regional values. It may be that the recent increase in
the number of structures and level of activity near CPF-1 is re-
lated to the reduced calf representation locally. Calf percen-
tages in the Kuparuk flood plain have been consistently lower
than regional estimates. The Kuparuk River segment of the WSR
area has always been an area of relatively high construction
activity and correspondingly low calf percentages.
Insect-induced Movements
Midsummer movements of caribou in the KDA were greatly affected
by weather-induced changes in insect activity. Radio-tracking
data and observations along the Oliktok Road (M. Rebus, pers.
commun.) indicated that many caribou moved to the coast from west
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.of CPF-1 and then continued east along the coast as long as in-
sect: harassment was.·· severe. Subsequent inland movements along
the Kupa:r:uk River and other drainages were apparently blocked at
the WSR. Caribo:u then'turned west, paralleled the WSR to CPF-1,
recrossed the Oliktok Road, and dispersed to the southwest. This
clockwise movement pattern was fi.rst noted in 1981 and occurred 3
times during 1982.
Few crossi,ngs of the WSR were observed during standard road sur-
veys in midsummer • 1982. Additional observations (B. Lawhead,
pers. cornrnun.) indicated that the Kuparuk River area was still an
important caribou movement corridor. However, increasing traffic
and development along the WSR have apparently changed the overall
pattern of insect-induced movements within the KDA. Movements
now appear to be primarily of a circular nature rather than as
north-south oscillations, and routes of access and egress are
primarily across the Oliktok Road, north of CPF-1. Fig. 4
·depicts our overall impression of midsummer movements within the
KDA.
LITERATURE CITED
Cameron, R. D., and K. R. Whitten. 1979. Distribution and
movements of caribou in relation to the Kuparuk Development
Area. First Interim Rep. to ARCO, EXXON, and SOHIO/BP,
March 1979. 32pp.
;:onrl 1980. Distribution and movement.s of -.....,......-----........ .--, ~··--.....--~.---..,... caribou in relation to the Kuparuk Development Area. Second
Alaska Interim Rep. to ARCO, EXXON, and SOHIO/BP, May 1980.
Dep. Fish and Game, Fairbanks. 35pp.
----'---"'""' , and W. T. Smith. 1981. Distribution and
movements of caribou in relation to the Kuparuk Development
Area. Third Interim Rep. to ARCO, EXXON, and SOHIO./BP.
Alaska Dep. Fish and Game, Fairbanks. 25pp.
, , and . 1983. Responses of
___ c_a_r_1.,..,, b,....ou to petroleum-related development on Alaska's Arctic
Slope. Alaska Dep. Fish and G~me. . Fed. Aid in Wildl.
Rest. Prog. Rep. Proj. W-21-2 and W-22-1, Job 3.18R.
Juneau. 75pp.
, , and
---a"'""l,.....,..t-e~rat1on of caribou movement
and Game. Fed. Aid in Wildl.
W-22-2, Job 3.29R. Juneau.
6
1984. Development and
patterns. Alaska Dep. Fish
Rest. Prog. Rep. Proj.
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White, R. G., B. R. Thomson, T. Skogland, s. J. Person, D. E.
Russell, D. F. Holleman, and J. R. Luick. 1975. Ecology of
c~ribou at Prudhoe Bay, Alaska. In Ecological investiga-
tions of the tundra biome in the Prudhoe Bay region, Alaska.
Biol. Pap., Spec. Rep. No. 2. Univ. Alaska, Fairbanks.
PREPARED BY:
Walter T. Smith
Game Biologist II
Raymond D. Cameron
Game Biologist III
Kenneth R. Whitten
Game Biologist II
SUBMITTED BY:
Wayne L. Regelin
Regional Research Coordinator
APPROVED BY:
Research Chief ,cz'b1vis1on oi uame
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--as of 1981 Roads
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Fig. 3. Distribution of caribou observed from the West Sak Road,
spring and sununer 1982. Note: Calves observed in May are short
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Fig. 4. summary of caribou movements within the Kuparuk Development Area, summe~ 1982.
Table 1~ Composition of Central Arctic Herd caribou on the
calving grounds west of the Kuparuk River, 1978-82.
% Calves/ Bulls/ Yearlings'
Year calves 100 COWS 100 cows 100 cows
1978 36 82 3 39 (40)
1979 37 85 7 26 (60)
1980 30 68 4 48 (50)
1981 40 85 9 22 (34)
1982 34 70 11 23 (60)
a ( ) = Yearlings/100 cows estimated from overwinter calf
survival counts (Cameron et al. 1983).
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Table 2. Caribou densities in the Kuparuk calving concentration
area north of the West Sak Road, 1978-82.
Year
1978
1979
1980
1981
1982 a (East} a (West}
Caribou/100 km 2
281
630
276
589
256
(234}
(534)
Cow-calf pairs/100 km 2
112
279
90
274
104
(95)
(218}
a East and west of the low density area along the Milne Point
Road.
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Table 3. Summary of total numbers and calf percentages of caribou observed from the
West Sak Road, 1978-82.
Inclusive No. of No. of groups No. of
Year survey dates surveys observed caribou observed % calves
1978 18 Jul-18 Aug 28
1979 26 Jun-21 Aug 31
1980 16 Jul-6 Aug 38
1981 15 Jun-7 Aug 86
1982
Precalving 13 May-26 May 13
Calving 1 Jun-18 Jun 2~' "· Summer 1 Jul-5 Aug 60
a ( ) = 1981 cohort (i.e., short yearlings) •
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190 1,670 25.2
438 2,692 22.6
343 4,552 19.8
1,120 14,148 17.8
136 412 (17.5)a
118 310 1.6
522 8,801 16.0
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Appendix A.
Distribution of Caribou Calving in Relation to the
Prudhoe Bay Oil Field
K. R. Whitten and R. D. Cameron
(Manuscript submitted for publication in the Proceedings of the
First North American Caribou Workshop)
ABSTRACT. The calving grounds of the Central Arctic Herd (CAH)
were surveyed annually from 1978 to 1982 to determine caribou
distribution and density. Consistently low numbers of caribou
and generally low percentages of calves were observed in the
Prudhoe Bay Oil Field. Mean densities of caribou in 5 other re-
gions of the calving grounds were 2 to 18 times higher than at
Prudhoe Bay, presumably due to avoidance of the oil field by par-
turient cows. So far, displacement of calving caribou from
Prudhoe has been to adjacent areas already used for calving. The
CAH has increased rapidly in spite of displacement from part of
its calving grounds. This paradox is best explained by the re-
latively low density of the CAH on its calving grounds. Effec-
tive density of CAH caribou on calving grounds is about one-third
to one-fifth that of the nearby Western Arctic and Porcupine
Caribou Herds, suggesting that CAH caribou have more options for
selection of a calving site.
15
Appendix B.
Factors Affecting Pipeline Crossing Success of Caribou
Walter T. Smith and Raymond D. Cameron
(Manuscript submitted for publication in the Proceedings of the
First North American Caribou Workshop)
ABSTRACT. Early simulation studies on the Arctic Slope of Alaska
showed that caribou would not pass freely beneath elevated pipe-
lines. Our recent observations during summer indicate that
crossing success varies with pipeline design, caribou group
structure, and a number of environmental stimuli. Absolute
barriers to caribou movement exist where surface-to-pipe clear-
ance is inadequate for physical passage, or when drifting snow
along road/pipeline complexes reduces the effective clearance.
Where pipeline elevation i-s sufficient, the outcome of an en-
counter is related to other circumstances. Factors that appear
to influence crossing success include group size/composition,
topography, insect activity, traffic level, and the intensity of
local construction, as well as road and/or pipeline configura-
tion. Present studies are aimed at describing local movements
and evaluating the effectiveness of special pipeline crossing
structures. Maintaining caribou passage through oil fields
requires careful planning based on an assessment of both local
and regional movements.
16
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Appendix c.
Reactions of Caribou to an Above-Ground Pipeline
on the Arctic Coastal Plain of Alaska
Walter T. Smith and Raymond D. Cameron
(Manuscript submitted to Arctic)
ABSTRACT. We describe in detail two instances in which large.
groups of mosquito-harassed caribou (Rangifer tarandus granti)
were followed for 8-12 hours as they repeatedly attempted to
cross an elevated pipeline in the Kuparuk Development Area near
Prudhoe Bay, Alaska. In 1981, 46% of a group of 917 eventually
crossed beneath elevated portions of the pipeline in 26 separate
attempts, 13% crossed a section of buried pipe in two attempts,
19% separated from the group and were not accounted for, and 22%
trotted parallel to the pipeline for 37 km and did not cross. In
1982, 26% of a group of 655 crossed under elevated portions of
the pipeline in 36 attempts, 37% crossed at a buried section in
one attempt, and 3 7% left the main group and could not be
accounted for. The majority of crossing attempts occurred near
intersections· of lakes with the road/pipeline complex, but cross-
ing success was highest at a section of buried pipe isolated from
road traffic.
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