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SUSITNA HYDROELECTRIC PROJECT
FINAL PHASE I REPORT
BIG GAME STUDIES
VOLUME VI I.WOLVERINE
Craig L.Gardner
and
Warren B.Ballard
ALASKA DEPARTMENT OF FISH AND GAME
Submi tted to the
Alaska Power Authori ty
MAY 1 7 198Z
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PREFACE
In early 1980,the Alaska Department of Fish and Game contracted with
the Alaska Power Authority to collect information useful in assessing
the impacts of the proposed Susitna~Hydroe1ectric Project on moose,
caribou,wolf,wolverine,black bear,brown bear and Da11 sheep.This
information,along with information on furbearers,small mammals,birds,
and plant ecology collected by th~University of Alaska,is to be used by
Terrestrial Environmental Specialists,Inc.of Phoenix,New York,in
preparation of exhibits for the Alaska Power Authority's application for
a-Federal Energy Regulatory Connnission license to construct the project.
The studies were broken into phases which conformed to the anticipated
licensing schedule.Phase I studies,January 1,1980 to June 30,1982,
were intended to provide information needed to support a FERC license
application.If the decision is made to submit the application,studies.
will continue into Phase II to provide additional information during the
anticipated 2 to 3 year period between application and final FERC approva~
of the license.
Wildlife studies did not fit well into this schedule.Data collection could
not start until early spring 1980,and had to be terminated during fall 1981
to allow for analysis and report writing.(Data continued to be collected
during winter 1981-82,but could not be included in the Phase I report.)
The design of the hydroelectric project had not been determined.Little
data was available on wildlife use of the immediate project area,although
some species had been intensively studied nearby.Consequently,it was
necessary to start with fairly general studies of wildlife populations
to determine how each species used the area and identify potential impact
mechanisms.This w~s the thrust of the Phase I Big Game Studies.During
Phase II,we expect to narrow the focus of our studies to evaluate specific
impact mechanisms,.quantify impacts and evaluate mitigation measures.
Therefpre,the Final Phase I Report is not intended as a complete assessment
of the impacts of the Susitna Hydroelectric Project on big game.
The reports are organized into the following eight volumes:
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Volume I.
Volume II.
Volume III.
Volume IV.
Vp1ume V.
Vp1ume VI •
Vp1ume VII.
Volume VIII.
Big Game Summary Report
Moose -Downstream
Moose -Upstream
Caribou
Wolf
Black Bear and Brown Bear
Wolverine
Da11 Sheep
ARLIS
Alaska Resources
Library &Information Services
~chorage,l\laska
SUMMARY
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During Phase I studies,6 wolverine (5 males,1 female)were
radio-collared in an attempt to identify potential impacts of
hydroelectric development on wolverine.A total of 114 point
locations were obtained;104 of the locations were of radiocol-
lared wolverine.The annual home range for an adult male (040)
was 627 km 2 (237 mi 2).Home range sizes for two males monitored
6 and 8 months were 378 km 2 (146 mi 2)and 272 km 2 (105 mi 2),
respecti vely.Comparing home range sizes for males from the
Susitna River Basin,northwestern Alaska,and northwestern
Montana,suggested that Susitna Basin male wolverine home ranges
were larger than those in Montana but smaller than those in
northwestern Alaska.Differences were probably related to prey
diversi ty and density.
An est~mated 65 to 123 wolverine inhabited the study area during
1980 and 1981 providing a density range of 1/76 km 2 (1/29 mi 2 )to
1/143 km 2 (1/55 mi 2)
Trappers and hunters harvested 27 wolverine from the study area
during'Phase I studies.Ninety-three percent (25/27)of the wol-
verine!trapped were along the borders of the core study area.
Harvest ·locations appeared related to accessibi 1i ty.
Wolverines were distributed throughout the
Availability and ,utilization of different
impoundment area.
habitat types by
radio-collared wol~erine were compared.There were apparent sea-
sonal shifts in halbi tat utilization fr:om tundra dominated habi-
!,
tats (pummer)to forested areas (winter).The shift was probably
influe~ced by avaiLable prey species;ground squirrels and cari-
I ibouinlsummerandI moose and small mammals in winter.Ecotones
I i
were f~und to be impbrtant throughout the study area.
I
"""Observations of sgcia1 and breeding behavior of wolverine were
described.
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Loss of habitat by inundation,road and transmission line con-
struction,and associated borrow pits will lower wolverine num-
bers in the study area.Indirect impacts due to prey reduction
could cause wolverine distribution shifts,and may increase com-
peti tion with other scavengers.and resulting in lower wolverine
densities.
Some addi tional data needs for Phase II studies were identified.
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TABLE OF CONTENTS
Summary
List of Tables
List of Figures
Introduction
M,ethods
Study Area
Results and Discussion
Distribution and Movements
Home Ranges
Population Estimate
Harvest
Habi tat Utilization
Social Behavior
Breeding Behavior
Potential Impacts
Recommendations for Phase I I Studies
Acknowledgements
Literature Cited
Appendix A.Use of Etorphine
and Xylazine to immobilize wolverines
Appendix B.Wolverine breeding behavior
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Page
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iv
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1
2
3
5
5
11
14
17
20
26
29
29
30
32
33
36
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LI ST OF TABLES
Page
Table 1.Tagging location and physical measurements of
wolverine captured in the Susitna River Basin
Study Area during Pha~e I studies,1980-1981.
Table 2.Status of the radio-collared wolverine cap-
tured in the Susitna River Basin Study Area
during Phase I studies,1980-1981.
6
7
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Table 3.Summary of home range sizes for 4 radio-col-
lared wolverine in the Susitna River Basin
Study Area during Phase I Studies,1980-1981.12
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Table 4.Range of·density estimates for wolverine in
the Susitna River Basin Study Area during
Phase I Studies,1980-1981.18
Table 5.Utilization by wolverine 040 of the different
habitats present within its home range.19
,-Table 6.Utilization by wolverine 042 of the different
habitats present within its home range.22
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Table-7.Utilization by wolverine 043 of the different
habitats present within its home range.23
Table 8.Utilization by wolverine 044 of the different
habitats present within its home range.24
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LIST OF FIGURES
Figure 1.Map of the wolverine study area during Phase
I Studies,1980-1981.
Figure 2.Locations of observed uncollared wolverine,
wolverine tracks and harvested wolverine
within the Susitna River Basin Study Area
during 1979-80.
Figure 3.Locations of observed uncollared wolverine,
wolverine tracks and harvested wolverine
within the Susitna River Basin Study Area
during 1980-81.
Page
4
8
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Figure 4.Home ranges of the 4 radio-collared wolverine
in the Susitna River Basin Study Area during
Phase I studies.13
....Figure 5.Boundary of the core area where density es-
timates were obtained in relation to the
entire study area.
Figure 6.Movements and home ranges of wolverines 040
and 050 during March,1981.
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INTRODUCTION
Few studies of wolverine (Gulo gulo)ecology have been conducted
in North America.Complications inhibiting wolverine research
have been related to the species being relatively uncommon,in-
habiting remote country and its naturally elusiveness (Van Zyll
de Jong 1975).The recent sophistication of radio telemetry
equipment has permitted ecological studies in northwestern
Montana (Hornocker and Hash 1981)and in northwestern Alaska
(Magoun 1979,1980).Hornocker and Hash (1981)indicated that
human disturbances could be detrimental to wolverine populations.
Van Zyll de Jong believed (1975)that wolverine populations in
Canada declined due to increased influence by man.
The geographic range of wolverine has declined drastically across
North America during the past century probably in relation to
human encroachment.However,in Alaska,wolverine populations
probably have not yet been seriously influenced.Wolverine num-
bers in Alaska today.are probably comparable to what was present
a century ago.However,the recent focus on resource development
in Alaska may cause significant reductions in wolverine numbers.
Currently under study is a proposal to construct a large hydro-
electric proj ect on the Susi tna River in southcentral Alaska.
The proposed impoundments and the accompanying roads,borrow
pi ts,construction camps and transmission lines are expected to
affect over 20,500 hectares.It seems inevitable that distur-
bances due to construction operations and the inevitable increase
in human accessibility will have effects on the area's wolverine
population.Therefore,this study was initiated in January,1980
prior to any substantial impacts of the Susi tna Hydroelectric
Project on wolverine.Specific objectives included:1)esti-
mation of wolverine abundance within the vicinity of the proposed
impoundments;2)determination of seasonal movement patterns;and
3)habitat requirements and food habi ts of this population.
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METHODS
Capture efforts were conducted during April and May 1980,and
again in February and March,1981.Helicopter capture techniques
(Baer et ale 1978;Ballard et ale 1981)and live traps similar to
those used by Hornocker and ~ash (1981)and Magoun (in prep.)
were used.Initially,a combination of 0.25 cc phencyclidine
HCl (100 mgjml Sernylan Bioceutic Lab.,Inc.)and 0.20 cc
Xylazine HC1 (100 mgjml,Rompun,Barrett Division of Cutter Lab-
oratories,Inc.)was used to immobilize wolverine.Because
Sernylan is no longer commercially available,a combination of
0.4 cc etorphine (l-mgjcc M-99,D-M Pharmaceuticals,Inc.)and
0.5 cc Rompun (100 mgjml)was used to capture the last 5 wolver-
ine.A technic;al paper describing the use of M-99 and Rompun to
immobilize wolverine is presented in Appendix A.Each captured
wolverine was aged,sexed,weighed,measured,ear tagged and
radio-collared.In this report each captured or necropsied wol-
verine is referred ~o by the last 3 digits of its assigned acces-
s:ton number.
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Radio collars
rubber and had
Each collar was
from the collar.
(Telonics,Mesa,AZ)were constructed of butyl
an inner circumference ranging from 29 to 39 em.
equipped with a whip antenna which extended 26 em
The entire unit weighed 230 g.
Radio locations were made approximately one per week throughout
the study period by methods similar to those described by Mech
(1974).Radio loc~tions were recorded on 1:63,360 U.S.G.S.maps
and the following parameters recorded:date,time,activity,
number of associates,topography,and general habitat type.Sea-
sonal and yearly home ranges were delineated by the minimum area
method (Mohr 1947).
Habitat classification followed Viereck and Dyrness (1980).How-
ever,density and height of the spruce component were estimated
and the habitat was classified only to level I I I.We estimated
2
wolverine habitat selectivity by comparing habitat type avail-
ability to actual use determined by relocation data.Vegetation
cover type maps (Ag.Exp.Stat.1981)of the study area were used
to estimate availability.
Wolverine habitat was also characterized by available prey spe-
cies.Known seasonal concentration areas of ungulates and small
mammals within the radio-collared wolverine home ranges were com-
pared to the wolverine's movements to determine if these wolver-
ine showed a fidelity toward these areas .Wolverine tracks were
followed on the ground during May and December 1980 in an effort
to gather information pertaining to food habits and activity pat-
terns.Tracks were initially found by aircraft,then followed on
foot.
Harvest records,wolverine and wolverine track sightings by pro-
ject personnel and the public were used to get an indication of
wolverine distribution within the study area.Capture locations
and sightings were recorded on 1:63,360 scale U.S.G.S.maps.
Wolverine carcasses were purchased from hunters and trappers in
Game Management Unit (GMU)13 for $10.00 per carcass.Each car-
cass was necropsied in an effort to quantify age structure of the
harvest and reproductive status of the area's population.Ani-
mals were classified juvenile or adult by the morphology of the
canine tooth (Rausch and Pearson 1972).
Study Area
Based upon the boundaries of the proposed impoundments and asso-
ciated borrow pits and roads in addition to wolverine di stribu-
tion,the area depicted in Figure 1 is considered the project
impact area for wolverine.The study area boundary follows the
basin boundary in the west to the base of the West and Middle
For~Glaciers,down the Susi tna River to its intersection with
the Tyone River,up the Tyone River to Tyone Lake,then a south-
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Figure 1.Map of the wolverine study area during Phase I Studies,1980-1981.
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the Oshetna River,along the Oshetna River to the peak of the
Talkeetna Mountains,follows the upper elevations of the
Talkeetna Mountains to the confluence of the upper north and
south forks of the Talkeetna River,then northwest to the basin
boundary.
Vegetation,topography and climatic descriptions have been des-
cribed by Skoog (1968),Bishop and Rausch (1974)and Ballard and
Taylor (1980),and Subtask 7 .12
RESULTS AND DISCUSSION
A total of 6 wolverine (5 males and 1 female)we~e captured and
radio-collared during Phase I studies (Table 1).Wolverine 040
was recaptured once to replace its radio.Fate of the tagged
animals during the study period :lS presented in Table 2.
Induction time for the 2 wolverine immobilized by the Sernylan
and Rompun combination were 36 minutes (14.5 kg male)and 11 min-
utes (9.5 kg female).Induction times for these 2 wolverine may
not be indicative of the normal induction times for Sernylan as
the drug was outdated.Magoun (pers.comm.)found the Sernylan-
Rompun dosage very effective in immobilizing wolverine in north-
western Alaska.
Distribution and Movements
Relocation data for 5 radio-collared w~lverine,sightings of un-
marked wolverine or wolverine tracks and ADF&:G harvest data
yielded a total of 144 point locations scattered throughout the
impoundment area (Figs.2 and 3).
Distribution seems to be complete throughout the impoundment
area;however,the data indicate that concentrations are centered
in generally,hilly topography above treeline.There are
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1 '1 1 1 J J 1 J J -1 1
Table 1.Tagging location and physical measurements of wolverine captured in the Susitna River Basin,1980.
Canine Canine
Accession Body Neck Head Head length Width
Number Date Location Sex Age Weight Length Girth Circum.Width t.eng th (mm)(mm)Comments
cm
116040 4/10/80 4.8km NW of M A
1 14.5kg 87.6 47.9 33.0 11.6 19.4 18.0 10.1 Right eye had
Clarence Lk.m:t.croopthelmia
3/25/81 W.of Goose Ck.M A
116041 4/19/80 5.6km upstream M A 15.5kg 87.0 49.8 34.3 11.4 16.5 23.8 9.3 Teeth badly
of mouth of worn
Fog Ck.
116042 4/19/80 Watana Ck.F A 9.5kg 80.0 38.1 27.0 9.8 14.6 21.3 7.6 Lactating
slightly,
had 2 kits
116043 5/06/80 4.0km SE of M U
2 17.7kg 81.9 44.9 11.5 15.9
of Standing
0'1 Bear -Lk.
116044 5/07/80 Across Susitna M u2 --
River from
Stephan Lk.
116050 3/06/81 Clarence Mt.H J3 17.7 96.0 51.0 34.3 11.3 13.8 23.0 8.0
1)A =Adult
2)U =Unknown
3)J =Juvenile
Table 2.Status of the radio-collared wolverine captured in the
Susitna River Basin Study Area during Phase I Studies,
1980 through 1981.
Accession Collaring
Number Date Sex Age Status
040 4/10/80 M A1 Natural mortality
3/25/-4/15/81
041 4/19/80 M A tagging mortality
4/21/80
042 4/19/80 F A Unknown -lost
U2 contact 8/12/80
043 5/06/80 M Unknown -radio
failure 12/04/80
044 5/07/80 M U Unknown -lost
J3
contact 10/09/80
050 3/06/81 M Unknown -lost
contact 3/25/81
1)A =Adult
2)U =Unknown
3)J =Juvenile
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Figure 2.Lociitions of observed uncollared wolverine,wo]veri!lI'trnc:lu::llId h;.rveHted wolverine within
the Susitna River Basin Study Area during 1979-HU.
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Figure 3.Locations of observed unco11ared wolverine.wolverine tracks and harvested wolverine within
the Susitna River Basin Study Area during 1980-81.
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inherent biases wi thin the data,as most of the track sightings
and the commercial harvest occurred during the spring (March-May)
when ..wolverine are generally moving to or inhabiting higher ele-
vations (Hornocker and Hash 1981).
Radio-tracking data suggest th_at changes in wolverine distribu-
tion occur throughout the year.Food availability probably
influences these shifts.Van Zyll de Jong (1975)in Canada sug-
gested that food availability influences changes in wolverine
distribution.We observed 3 different movements by wolverine
which seemed to be induced by food supply.Details of these
observations follow:
During 1980,Nelchina caribou (Rangifer tarandus)calving ex-
tended from 15 May to 10 June (Pitcher 1980).During that period
wolverine 040 was located on 6 of 9 (67%)occasions within the
calving ground.Although wolverine 040 was never observed with a
dead caribou,a number of dead calves were present (unpub.data).
The month prior to calving,040 was observed on the calving
grounds 1 of 5 (20%)occasions .
From collaring (April 1980)until mid-December 1980,we observed
limited use of the Susitna River by the 3 radio-collared wolver-
ine whose home ranges bordered the river.Only 9 percent (6 of
67)of the relocations were within 1.6 km (1 mile)of the river
and only 3 actual crossings were documented.However,from mid-
December,1980 to late March,1981,wolverine 040 narrowed its
ac:tivi ties to 14%of its normal home range and exhibited an in-
creased fidelity to the Susitna River~as 53.8%(7 of 13)relo-
cations were within 1.6 km (1 mile)of the river.This same area
had high densities of moose (Alees alees)(Ballard et al.1980).
In addition to wolverine 040 at least 4 wolves (Canis lupus)and
t other wolverine (050)were present in the area suggesting con-
centration of predators and scavengers in this high density moose
area.
10
Wolverine 044 was collared on the Susi tna River across from
Stephan Lake on 7 May 1980.By 13 June 1980 044 had moved
approximately 70 km to the vicinity of Kosina and Tsi si Creek
drainages.It remained there until 26 August when it began
moving back toward Stephan Lake.On 7 October,044 was located
6 km east of Stephan Lake.Th~s extensive movement went from a
heavily timbered habitat to an upland shrub and tundra habitat.
We suspect these movements were correlated to Arctic ground
squirrel (Spermophi/us parry;i)emergence and subsequent hiber-
nation.Densities of ground squirrels were more abundant in
these higher,more open habitats (McDonald 1980).Ground
squirrels and marmots (Marmota caligata)were important food
species for wolverine in both the Brooks Range (Magoun 1979,
1980)and northwestern Montana (Hornocker and Hash 1981)..In
addi tion,moose densities around Stephan Lake and Tsisi Creek
were estimated as medium and low,respectively (Ballard et al.
1980).
Magoun (pers.comm.)suggested that male wolverine display an
increase in their movement patterns just prior to and during
breeding.We were unable to confirm this hypothesis in the
Susitna Basin,however,this may be due to sampling biases.We
compared percent of home range utilized from May through.July to
other 3 month blocks and found no significant differences
(P 0.05).
Home Ranges
Radio-collared wolverine were located on 104 occasions during
Phase I studies.Home ranges were determined for 5 wolverine,
however only the home range of wolverine 040 (627 km 2 ,242 mi 2 )
represents an annual home range (Table 3 and Fig.4).
Direct comparison of home range sizes of Susitna wolverine with
findings for other radio-telemetry studies is difficult due to
the differences in sampling periods.Magoun (1979)reported
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Table 3.Summary of home range sizes for 5 radio-collared
wolverine in the Susitna River Basin Study Area
during Phase I Studies,1980 through 1981.
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Accession Home 2 Period
Number Sex Est.Age Range (km )Monitored
040 M Al 627 April,1980-
April,1981
042 F A 86 April,1980-
U2 Aug.,1980
043 M 272 May,1980-
~Dec.,1980
044 M U 378 May,1980-
J3
Oct.,1980
~050 M 89 March,1981
1)A=Adult
2)U =Unknown~
3)J =Juvenile
12
Figure 4.Home ranges of the four radio-collared wolverine in the Susitna River Basin Study Area
during Phase I studies.
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summer home ranges for male and female wolverine in northwestern
Alaska as 615 km 2 (237 mi 2 )and 187 km 2 (71 mi 2 ),respectively,
while Hornocker and Hash (1981)reported annual home ranges of
422 km 2 (163 mi 2)and 388 km 2 (150 mi 2)for males and females,
respectively in northwestern Montana.Krott (1959)speculated a
male wolverine could have a te~ritory as large as 1,000 to 2,000
km2 (386 to 772 mi 2)depending on food supply and competition
from other species.Comparing home range sizes for males from
study areas in northwestern Alaska,the Susi tna River Basin and
northwestern Montana,·it appears that male wolverine in Alaska
have a larger home range.However,home range requirements for
lactating females were similar between Susitna Basin,Alaska and
northwestern Montana.The larger home ranges of wolverine in
Alaska are probably related to both lower di versi ty and density
of prey.
Population Estimate
An accurate estimation of wolverine density within the impound-
ment area is difficult to obtain with the avai lable data.More
information is needed on wolverine home range sizes and overlap,
habitat utilization,sex and age ratios,mortality,immigration
and emigration.Within the 2,727 km 2 (1,052 mi 2 )core area where
intensive radio-telemetry studies were conducted (Fig.5), a
minimum of 9 adult wolverine occurred providing a minimum density
estimate of 1 adult wolverine/303 km2 (1/117 mi 2)•However,we
believe a more reasonable estimate might be obtained by utilizing
home range data if certain assumptions are made:1)wi thin
sexes,home ranges are essentially mutually exclusive but overlap
occurs between sexeSi 2)home ranges remain constant all year i
3)equal use of all available habitatsi and 4)no significant
immigration or emigration.During this study the annual home
range for one male wolverine was 627 km2 •Two additional esti-
mates of 272 and 378 km 2 were obtained for 6-8 month periods.
Between January and April,the one male wolverine for which
annual data exi sts increased its home range by 228 km2 •Thi s
14
Figure 5.Boundary of the core area where density estimates were obtained in relation to the entire
study area.
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UPPER SUSITNA RIVER BASIN
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increase in home range size during the winter months may have
been related to a reduction in food availability.If all male
wolverine have simi lar movements then average annual male home
ranges in the Susi tna Basin probably range from 500 km 2 to 627
km 2 •This estimate appears comparable with the male home ranges
found by Magoun (1979)in northwestern Alaska.Both estimates
were used for our density calculations.Also,only the home
range of a lactating female was determined during this study,
which was not representative of a female's annual home range.
Hornocker and Hash (1981)reported an annual home range of 388
km2 for females in northwestern Montana while Magoun (1979)re-
ported female home ranges of 185 km 2 (summer home ranges)in
northwestern Alaska.Magoun's estimates are probably not
relective of annual home ranges because the data were derived
primari ly during summer.However,for our density calculations
we used a combination of estimates.With the above assumptions
and the different estimates of home range sizes we estimated that
the study area supported from 11 to 21 adult wolverine,yielding
an estimated adult density range of 1/248 km 2 (1/96 mi 2 )to 1/136
km 2 (53 mi 2)•
Necropsy data from carcasses collected in the Susi tna Basin,
Alaska and northwestern British Columbia (Liskop et al.1981)
were used to estimate the number of pre-adult wolverine in the
study area.Based on Susitna River data,8 of 15 (53%,similar
to Rausch and Pearson 1972)mature females were reproductively
active (assuming that pregnant or post-partum females were
equally vulnerable to trapping or hunting as non-pregnant wolver-
ine.Liskop et al.(1981L however,determined that in north-
western British Columbia 23 of 26 (88%)mature females were re-
productively active.According to Rausch and Pearson (1972)the
effective reproduction of wolverine is 2.a ki tS/li tter.There-
fore,the estimated number of kits added annually to the study
area's population ranges from 6 to 26.This yields a total popu-
lation estimate between 16 and 46 wolverine without mortality,
immigration and emigration factors included.The above calcula-
tions indicate a total density ranging from 1 wolverine/170 km 2
16
(66 mi 2 )to 1 wolverine/59 km2 (23 mi 2 ).(Table 4.)Wolverine
densi ties and home range size may be related to food supply
(Hornocker and Hash 1981).It is generally accepted that food
abundance and diversity normally decrease from southern to north-
ern latitudes (Fisher 1960 1 Stehli 1968).If wolverine densities
are partially related to density of prey,then wolverine densi-
ties should be greater Hornocker and Hash's study area in north-
western Montana than in Alaska.Thus,within Alaska,the Susitna
Basin should support greater densities than the western Brooks
Range.Hornocker and Hash (1981)and Magoun (1979)reported
estimated densities of 1/65 km 2 (1/25 mi 2)and 1 adul t/149 km 2
(1/58 mi 2 )in northwestern Montana and Alaska,respectively.
Comparing the density range calculated for the Susi tna Basin
(Table 4)with these results,the best wolverine density estimate
for the core study should be between the estimates for Montana
and northern Alaska and probably ranges between 1/75 km 2 (1/29
km 2 )and 1/143 km2 (1/55 mi 2)•
The total study area (Fig.5)encompassed approximate 9 1 350 km 2
(3,609 mi 2)•Using the core area density estimate and extrapo-
lating to the total study area provides a population estimate
between 55 and 154 wolverinej however a more reasonable estimate
is probably 65 to 123 wolverine.
Harvest
A total of 27 wolverine were harvested from the study area during
Phase I (1979-1981)studiesj 20 during 1979-80 and 7 during 1980-
81.The low take during 1980-81 was probably due to poor weather
and snow condi tions.
Harvest locations (Fig.2 and 3)may also provide ~dditional in-
sight into wolverine movements and food habits.A comparison of
annual harvests with fall 1980 moose densities and movements
(Ballard et al.1981)suggested that 6 of 8 and 4 of 5 wolverine
harvested in 1979 and 1980,respectively,were from areas of
medium to low moose density.This suggests that wolverine were
17
-
-
-
-
-.
1 j "J J 1 J I J
Table 4.Range of density estimates for wolverine in the Susitna River Basin Core Study Area during Phase I Studies,
1980-81.
Estimated
1/of Est.II Density
Estimated 1/Estimated 1/reproductive of kits Est.total est.
of males Source of females Source females Source produced 1/wolverine (l/km II)
5 This study II 5 This study 3 This study 6 16 11170
est.from est.from 4 Liskop et al.~I 8 18 1/151
known animals known animals
4 Magoun il 7 Hornocker il 4 This study 8 19 1/143
and Hash 6 Liskop et al.11 12 23 1/119
5 This study 7 Hornocker il 4 This study 8 20 1/136
and Hash 6 Liskop et al.11 12 24 1/114
4 Magoun il 15 Magoun il 8 This study 16 35 1/78
13 Liskop et al.11 26 45 1/61
5 This study 15 Magoun il 8 This study 16 36'1/76
13 Liskop et al.11 26 46 1/59
i-"co
1)Based on 2 kits per litter (Rausch and Pearson (1972).
2)Assumed 1:1 sex ratio.
3)Number of reproductively active females determined by carcass data collected by Liskop et al.(1981)•
4)Based on home range data collected by Magoun (1979).
5)Based on home range data collected by Harnocker and Hash (1981).
19
~,
-
-
probably feeding on moose to an undetermined extent.
Harvest locations may also indicate the degree of trapping pres-
sure in the study area.Only,2 and 0 wolverine were trapped
within the core area (Fig.5)during 1979-1980 and 1980-1981,
respectively.Obviously,the maj ori ty of the trapping pressure
occurred along the edge of the study area.Harvest occurred near
waterways and winter trails.The distance from populated areas,
to the core area,the topography and habitats of the core area,
and the lack of trails within the core area,probably prohibited
this area from being efficiently trapped.
However,with the construction of the.Devil Canyon-Watana dam
system,there will be an increase in accessibility into the area
and correspondingly,a probable increase in wolverine trapping
pressure.
If construction occurs,an allowable harvest level should be
determined if the area's wolverine population is to remain
viable.Van Zyll de Jong (1975)has reported that overharvesting
would be detrimental to a wolverine population due to their low
intrinsic rate of increase.However,increased trapping pres-
sure,probably would not detrimentally affect the area's popula-
tion initially,due to the fact that large parcels of wolverine
habitat surround the area and therefore emigration into the area
may compensate trapping losses.
Habitat Utilization
Within each of the 4 radio-collared wolverines'home ranges,6 to
11 habitat types were present.All locations were plotted by
habitat type to compare use in relation to availability.
Wolverine 040 was observed in 7 of the 11 different habitat types
wi thin its home range.By frequency of observation,low shrub
(37.5%),sedge grass tundra (22.5%),open spruce (20%)and mixed
open spruce (10%)habitats were preferred (Table 5).However,
20
040 utilized low shrub habitat in a lower proportion than what
the habitat was available,(37.5%vs.56.4%>.while 040 utilized
sedge grass and open spruce habitats to a greater proportion than
the habitat availability,(22.5%vs 18.5%and 20%vs 9%,respect-
ive1y).Seasonal habitat preferences were also apparent.Sev-
enty-five (6 of 8)percent of open spruce usage occurred between
mid-December and 1 April and 67%(6 of 9)usage of sedge grass
tundra habi tats occurred between 25 May and 1 September.
Wolverine 042,a lactating female with 2 kits,summered in an
area of low habitat diversity as three habitat types covered 86%
of her home range.The predominant habitat type,mat and cush-
ion/sedge grass tundra,was used in approximately the same pro-
portion as it occurred (Table 6).A cursory examination indi-
cates that the woodland spruce and open tall shrub habitats were
preferred and the sedge grass and alpine herbaceous tundra habi-
tats were avoided.However,the small sample size may be a major
bias.
Wolverines 043 and 044 displayed preference for ecotone habitats
since 37.6%(9/26)and 61.5%(8/13)of their relocations were
present in these transition zones.Preference or avoidance be-
havior toward homogenous habitat types was impossible to separate
due to their apparent preference of ecotona1 areas (Tables 7
and 8).
All of the radio-collared wolverine displayed an increased use of
lower elevation areas during winter and late spring (December
through March).The mean seasonal values are 760 m (winter)and
950 m (spring),940 m (summer)and 950 m (fall).Hornocker and
Hash (1981)also reported an e1evational decline during winter
for wolverines in northwestern Montana.
21
-
...,.
-
-
.-
-
Table 6.Utilization by wolverine 042 of the different habitats pre-
sent within its home range.
Habitat
Habitat Availability Expected if of Actual if of Observed Use
type (%)Relocations Relocations (%)
Mat and
Cushion/
sedge 49.7 9 10 55.5
grass
tundra
Sedge
Grass 21.2 4 2 11.1
tundra
Alpine
.-Herbaceous
tundra 15.3 3 1 5.5
Open 6.5 1 3 16.6.....tall shrub
woodland 3.6 1 2 11.1
spruce
.-
22
Table 7.Utilization by wolverine 043 of the different habitats present within its
home range.
open mixed forest/mat
cushion/sedge grass
tundra ecotone
N
W
Distinct Habitat
Types /I Ecotones
mat cushion/sedge
grass tundra
open tall shrub
willow shrub
bush shrub
open mixed forest
mat cushion/sedge
grass tundra/open
tall shrub ecotone
Habitat
Availability
(%)
49.1
20.0
12.5
5.2
4.8
Expected II of
Relocations
12
5
3
1
1
Actual /I of Observed use
Relocations (%)
3 U.S
7 26.9
4 15.3
0 0
3 u.s
4 15.4
2 7.7
open mixed forest/
open tall shrub
ecotone
birch shrub/mat
cushion/sedge grass
tundra ecotone
birch shrub/open
tall shrub ecotone
1
1
1
3.8
3.8
3.8
J J J J _J 1 )J ]J ~--J
-J 1 ~--1 1 1 )]J ))1 )
Table 8.Utilization by wolverine 044 of the different habitats present within its
home range.
Habitat
Distinct Habitat Availability Expected II of Actual /I of Observed use
Types &Ecotones (%)Relocations Relocations (%)
low shrub 21.8 3 2 15.4
sedg·e grass
tundra 20.7 3 0 0
mat cushion/sedge
grass tundra 16.6 2 1 7.7
woodland spruce 15.8 2 0 0
N willow shrub 6.4 1 1 7.7
.p-
low shrub/sedge
grass tundra ecotone ----3 23.1
woodland spruce/birch
shrub ecotone ----2 15.4
open spruce/open
mixed forest ecotone ----1 7.7
woodland spruce/low ----1 7.7
shrub/sedge grass
tundra ecotone
woodland spruce/birch ----1 7.7
shrub/closed spruce
ecotone
For carnivores and scavengers it is probably more accurate to
classify habitat by available prey species.It is well known
that wolverines are well adapted for carrion feeding and also,
that it is important in the wolverine diet (Hornocker and Hash
1981,Rausch and Pearson 1972,Pul1iainen 1968,Haglund 1966,
Krott 1959).However,other authors indicate that wolverine use
of smaller prey such as marmot,snowshoe hare (Lepus americanus),
Arctic ground squirrels,microtine rodents,and birds is exten-
sive,especially in the spring and summer (Hornocker and Hash
1981,Magoun 1979,and Krott 1959).Magoun (1979,1980)found
wolverine feeding on microtines,ground squirrels,marmots and
caribou between April and September in northwestern Alaska.In
the same report,she speculated that th~ir diet shifts primarily
to microtines and ptarmigan (Logopus spp.)during the winter due
to caribou migration and ground squirrel and marmot hibernation.
Scat analysis by Magoun (1980)further exhibits the importance of
carrion,ground squirrels,microtines,and birds.
In the Susi tna Basin,there is a pronounced movement toward
higher elevation areas in the spring,summer,and fall months.
During this time,there are an abundance of ground squirrels,
pikas (Ochotona collaris)and marmots throughout the high country
(McDonald 1981).Also present in the tundra habitats are 13 spe-
cies of ground nesting birds (Cooper,pers.comm.).Wi thin part
of wolverine 040's horne range,the main summering concentration
of Ne1china caribou occurs primarily between 4,000 to 6,000 feet
(Pitcher 1980).Sixty-seven percent of 040's locations between
15 May and 1 September were within this tundra habitat.Wolver-
ine 044 moved a straight line distance of 70 krn from an open
spruce habitat '(1400'elevation)to a tundra habitat (3250'ele-
vation)in occurrence with small mammal emergence,caribou in-
habi tance and bird nesting season.It remained above treeline
until 26 September 1980.
The high number of locations of wolverines 043 and 044 wi thin
ecotones is probably related to availability of food.It is
25
-
-
-
-
-
-
-
-
....
r
i
"""",
,~
well known that ecotones are usually high in plant diversity and
support a diverse microtine population.Unfortunately,we have
no quanti tati ve data on prey densi ties in these areas.
Winter food habits data collected from fixed wing aircraft and
from ground tracking indicates .the increased importance of lower
elevations and forested areas.The Susi tna River,from the
Gauging Station to the Big Bend (predominately open spruce habi-
tat)supports a high density of moose during the winter (Ballard
et al.1980).Also,microtine rodents were more abundant in the
open spruce habitat.From mid-December to 1 April,75%of wol-
verine 040's locations were within that area.During March 1981,
we knew that at least 2 wolverine were using that area and obser-
ved use of 3 different moose carcasses.
Ground tracking during May and November 1980 and April 1981 in-
dicated that wolverine were preying on small mammals.Tracks
were followed through a variety of habitats and and it appeared
that the wolverine were hunting red squirrels (Tamiasciurus
hudsonicus),ground squirrels and grouse,(Canachiles
canadensis).
Social Behavior
There is a discrepancy in the literature concerning wolverine
spacing.Koehler et al.(1980)found territorial defense to be
ncmexistent in Montana wolverines.Magoun (1980),however,docu-
mented adult female wolverines excluding other adult females from
their home ranges at least from April through September.Both
authors concur that there is overlap between sexes.We did not
collect adequate data to infer exclusion or overlap of home
ranges within sexes.However,during March 1981 we monitored
movements of wolverine 040 (adult male)and wolverine 050 (juven-
ile male),which occupied part of 040's annual home range
(Fig.6).During March we located each wolverine 6 times and
found their home range sizes to be comparable,79 km 2 to 80.6 km 2
26
Figure 6.Movements and home ranges of wolverines 040 and 050 during March,1981,
5.2
10.4
4.4
5.6
Distance
(km)
Death
Location
1
2
3
5
D
P1SH NCl WUlI..ft KllVlC(
OCTOKR It"
u.S.DEPARTWEHI'rI ..TVlIOR
c-.III I_DIS IlK WAI'
lIllU1'MCOfhIAL IlAIUG:I'MIA.A&..UKA
UPPER SUSITNA RIVER BASIN
TWO DAM,PLAN
~
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Date Location
#
3/06
3/19
3/23
3/25
\
I
\-~<-~
)
'-',...,1
_J
<;:./
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\
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,c:J 3/25-
~c9'"4/15
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1.-'
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UPPER SUSITNA RIVER PROFILE
IUYIIl "'LEI IIG-UG
.•..
~"
~.
\,",
:-'1
:.;0
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SCALf
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..'.
\:~"i:'"..:.\'.'<.'~II..'.- --.,~~",L.:::::t?:I~1±·I~·EFf3••.':'_._-'W .",.-"-
•..'10
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-
for 040 and 050,respectively.During this time,there was only
a small amount of overlap.However,we monitored the 2 wolverine
on the same day 4 times and found the distance separating the 2
wolverine ranged from 4.6 to 11.0 km(2.9 to 6.9 mil.During
the first week in April we found 040 dead and lost contact with
050.
~rF.
d "We investigated 040's death site on 17 April 1981.There were 2
sets of wolverine tracks in the area,both coming from the south
side of the river.One of the wolverine had killed and consumed
..
a spruce grouse.Where the trails crossed there was a shallow
depression in the snow measuring 0.75 m (30 inches)by 1.0 m (39
inches).Under 15 cm (6 inches)of snow,wolverine 040 was
cached.Close examination revealed that the other wolverine had
fed extensively consuming all the musculature,internal organs,
and geni tali a .The head was intact wi th 040's tongue lacerated.
Where the wolverines made contact,there was an extensive network
of tracks but no sign of conflict.Evidence was not adequate to
accurately infer if 040 was killed by the other wolverine or had
died of another cause and then was fed on and cached by that wol-
verine.However,we ruled out starvation during March and Apri 1,
because 040 had been observed feeding on a minimum of·3 moose
carcasses during the previous month.There was an increase in
spermatogenesis as breeding season (Rausch and Pearson 1972).
Magoun (1980)suggests that with the onset of breeding season
aggressive behavior by the resident adult wolverine may be re-
lated to the di spersal of immature animals (9-14 months).The
direction of tracks,the close proximity of previous locations,
the loss of contact with wolverine 050 and the onset of breeding
season gives circumstantial evidence that the 2 wolverines in-
volved.were 040 and 050 and that wolverine 050 possibly killed
wolverine 040.
28
Breeding Behavior
There is limited knowledge concerning breeding behavior of wol-
verine.Only 3 occurrences of breeding have been witnessed in
the wild and these were observed from fixed-wing aircraft (Magoun
1980).On 9 June 1981 a pair.of wolverine on Watana Mountain
were observed breeding.A description is presented in Appen-
dix B.
Potential Impacts
The most obvious potential impact of the susi tna Hydroelectric
Project on wolverine is loss of over 20,600 hectares due to in-
undation and associated construction of camps,roads,borrow
pi ts,and transmission corridors.Human-wildlife contacts may
also be severe.According to Robert J.Krogseng,Resident
Manager for Terrestrial Environmental Specialists,Inc.,at the
height of construction there wi 11 be 5,000 workers wi thin the
area.The potential for an increase in both harassment and
hunting and trapping pressure due to human activity and easier
access into the area is likely and can be seriously detrimental
to a low densi ty species like wolverine.
The scavenging nature of wolverine could bring them in contact
wi th the camps lending to additional mortality if garbage dis-
posal and the use of firearms are not strictly regulated.If the
population is now being harvested at maximum sustained yield this
could have a serious impact on the population.
Once construction is completed,a permanent core area will·be
built to house a minimum of 120 maintenance workers (Robert
Krogseng pers.comm.).The long term effect on wolverine distri-
bution will probably be a significant shift away from the perma-
nent facilities.This will probably cause a decrease in wolver-
ine numbers due to an increase in competition for food,mates and
territories.
29
-
-
-
-
-
....
-
-
-
The loss of habitat as it affects the wolverine's prey species
will probably cause reductions in wolverine densities.A de-
crease in the food base would probably increase competition be-
tween wolverine,and between wolverine and other scavengers and
predators.These changes could al terhome range size and sea-
sonal movements and result in lower wolverine densities.
An additional potential long term impact on wolverine is that
once the project is operational,commercial development may occur
on lands adjacent to the impoundments since much of the area may
be in private ownership due to the Alaska Native Claims Settle-
ment Act.
Recommendations for Phase I I Studies
Phase I studies have identified the needs for additional data
collection to further assess the impacts of the Susi tna Hydro-
electric project on wolverine.Additional research should in-
clude the following projects:
(1)The segment of the wolverine population which inhabits areas
close to Watana Camp and High Lake Lodge should be radio-
collared in order to more accurately assess the impacts of
human activity on wolverine movements and seasonal distribu-
tion.
(2)Establish radio contact with additional wolverine in order
to obtain data concerning home range size,habitat use,
population dynamics,emigration and mortali ty.
(3)Monitor radio-collared adult females during late winter-
early spring in order to .locate any possible dens.Document
si te characteristics in order to determine any habitat or
topographical requirements.Scats should be collected from
the den to evaluate a denning female I s food habi ts.
30
(4)Evaluate winter food habits by ground tracking radio-col-
lared wolverine.Scats should be collected and the location
where the scats found recorded.If possible,caches and the
food items identified.
(5)Carcasses should continue ,to be purchased from GMU-13 trap-
pers and hunters.Age,reproductive status and condition of
the harvested animal can be determined.Data collected from
the harvested wolverine will aid in density estimates and
indicate distribution.
(6)Continue to monitor radio-collared wolverine to gather
annual home range data,to evaluate seasonal movements and
distribution and to determine if any type of terri toriali ty
exists wi thin sexes.
(7)Radio-collar wolverine inhabiting the downstream study
area.Quantify wolverine harvest mortality,movement pat-
terns and distribution in an area very accessible to human
influence.
31
-
-
-
-
~:
-
-
.....
ACKNOWLEDGEMENTS
Alaska Department of Fish and Game employees Paul Arneson,
Dau,Dennis McAllister,Sterling Miller,Chuck Schwartz
Robert Tobey participated in the tagging operation.
Jim
and
"""!
"""i
......
Vern Lofstedt,Kenai Air Service,piloted the helicopter and par-
ticipated in the processing of the immobilized animals.Ken
Bunch,Sportsman's Flying Service and Ai Lee,Lee's Air Service,
piloted fixed-wing aircraft both during tagging operations and
during monitoring activities.The experience and helpful cooper-
ation of these individuals contributed greatly to the success of
this project.
Karl Schneider,ADF&G,provided guidance and support throughout
the project and made a number of helpful suggestions for improv-
ing this report.Albert Franzmann (ADF&G)necropsied the tagging
related mortality.
Jim Dau,Carolyn McCormick and Russ Holder assisted wi th data
analysi s and data tabulations.Suggestions from Jim Dau were
especially helpful.
32
LITERATURE CITED
Agricultural,Experimental Station.1981.Vegetation studies.
Susi tna Hydroelectric Proj ect Subtask 7.12.
Baer,'H.C.,R.E.Severson,and S.B.Linhart.Live capture of
coyotes from a helicopter with ketamine hydrochloride.J.
Wildl.Manage.42:452-454.
Ballard,W.B.,D.A.Cornelius,and C.L.Gardner.1981.
Moose-Upstream studies.Susi tna Hydroelectric Proj ect Sub-
task 7 .11.91 pp .....
Ballard,W.B.,'R.O.Stephenson and T.H,Spraker.1981.Nel-
r-china Basin wolf studies.Alaska Dept.Fish and Game.P-R
Proj.Final Rep.W-17-8, W-17-9,W-17-10 and W-17p11.
201pp.
Ballard,W.B.,and K.P.Taylor.1980.Upper Susitna Valley
moose population study.Alaska Dept.Fish and Game.P-R
Proj.Final Rep.,W-17-9,W-17-10 and W-17-1l 102pp.
Bishop,R.o H.and R.A.Rausch.1974.Moose population
fluctuations in Alaska,1950-1972,Nat.Can.101:559-593.
-Bjarvall,A.1980.
denning period.
A study of the wolverine female during the
In Press.
Burkholder,B.L.1962.Observations.concerning wolverine.J.
Mammal.43:263-264.
Fisher,A.G.1960.Latitudinal variation in organic diversity.
Evaluation 14:64-81.
Hagland,B.1966.De stora roudjurens vintervenor [Winter
habi ts of the lynx (Lynx lynx)and wolverine (Gulo gulo)as
revealed by tracking in the snow].(Summary in English).
Vil trevy (Stockholm).4:81-299.
33
Hornocker,M.G.and H.S.Hash.1981.Ecology of the wolverine
in northwestern Montana.Can.J.of Zool.59:1286-1301.
Koehler,G.00.,M.G.Hornocker,and H.S.Hash.1980.Wolver-
ine marking behavior.Can.Field-Nat.94:339-341.
Krott,P.1959.Der Vielfrass.Monographier der Wildsaugetiere
(Gottingen)13:1-159.
Liskop,K.S.,R.M.F.S.Sadleir and B.P.Saunders.In press.
Reproduction and harvest of wolverine (Gulo qulo)in British
Columbia.J.A.Chapman and D.Pursley,Co.Eds.Worldwide
Furbearer Conference Proceedings.Frostbury,Maryland.
MacDonald,S.O.1981.Species and abundance of small mammals.
Abstract to T.E .S.
Magoun,A'.J.1979.Studies of wolverines on and adjacent to
NPR-A.Chapt.4 in Studies of Selected Wildlife and Fish
and Their Use of Habitats on and Adj acent to NPR-A 1977-78.
U.S.Dept.of Interior.
Magoun,A.J.1980.Ecology of wolverines in an Arctic eco-
system.Alaska Cooperative Research Unit,Univ.of Alaska.
Progress Report.27 pp.
Mech,L.D.1974.Current techniques in the study of exclusive
wilderness carnivores.Proc.of XI Intl.Congress of Game
Biol.315-322pp.
-
-
"""I
Mohr,C.O.1947.Table
American small mammals.
of equivalent populations
Am.Midl.Nat.37:223-249.
of North
Pi tcher,K.W.1980.Caribou.
Subtask 7.11.36 pp.
34
Susitna Hydroelectric Project
-
.....
Pulliainen,E.1968.Breeding biology of the wolverine (Culo
gulo L.)in Finland.Ann.Zoo1.Fenn.5:338-344 .
Rausch,R.A.and A.M.Pearson.1972.Notes on the wolverines
in Alaska and Yukon Territory.J.Wildl.Manage.
36:249-268.
~Skoog,R.o.1968.Ecology of caribou (Rangifer tarandus
granti)in Alaska.PhD.Thesis,Univ.of California,Berke-
ley,California.699 pp.
Stehli,F.
recent
G.1968.
model.
Taxonomic gradients in pole
In Evolution and Environment,
location the
ed.E.T.
Drake,pp.163-227.New Haven:Yale'Univ.Press.
-Viereck ,L.A.I and C.R.Dyrness.1980.
fication system for vegetation in
Service,Gen.Tech.Rep.PNW-106,28pp.
35
A preliminary classi-
Alaska.U.S.Forest
.-
~I
Appendix A.Paper describing the use of M-99 and Rompum to immo-
bilize wolverine.
USE OE'ETORPHINE AND XYLAZINE TO IMMOBILIZE WOLVERINES
WARREN B.BALLARD AND CRAIG L.GARDNER 1
Abstract:,Seven wolverines were successfully immobilized by
darting from helicopter using a mixture of etorphine HCl (EHc)
and xylazine HCl (XHC1).No adverse effects were observed fol-
lowing recovery.The major advantage of using EXHCl was that it
allowed rapid recovery.A dosage of 9.4 mg EHCl with 50 XHCl was
that it allowed rapid recovery.A dosage of 0.4 mg EHCl with 50
mg XHCl was recommended for 12.6-17.7 kg wolverine to be darted
from helicopter.
INTRODUCTION
There is a paucity of literature concerning the capture and immo-
bilization of free-ranging wolverine (Gulo gulo).KetamineHC1 2
has been successfully utilized to immobilize wolverines caught in
barrel traps but recovery required 3-8 hours.3 Phencyclidine
HC1 3 has also been successfully used by darting from a.heli-
copter4 but the drug is no longer commercially available.During
a study of wolverine ecology in remote southcentral Alaska it was
desirable to capture and immobilize wolverine without using time
consuming trapping procedures and have rapid recovery so that
sedated animals would not be abnormally exposed and vulnerable
1
2
3
4
Alaska Department of E'ish and Game,P.O.Box 47,Glennallen,
Alaska 99588.
VetelarR ,Parke,Davis and Co.,Detroit,Michigan.
SernylanR ,Bio-ceutic Laboratories,Inc.,St.Joseph,
Missouri.
A.Magoun,Personal communication,University of Alaska,
College,Alaska.
36
to extreme air temperatures and hunting and trapping mortality.
This paper reports on the successful immobilization of wolverines
with a mixture of etorphine HC1 5 (EHCl)and xylazine HCl'(XHCl)
administered by darting from a helicopter.
MATERIALS AND METHODS
Wolverine were captured in spring and fall of 1980 and 1981 in
the upper Susi tna River Basin of southcentral Alaska,approxi-
mately 230 krn northeast of Anchorage.Descriptions of the are
have been reported elsewhere.2,4,5
Wolverine were located and darted from helicopter 7 similar to
methods described for wolves (Canis lupus).1 A mixture of 0.4 mg
EHCl (1 mg/ml)and 50 mg XHC1 (100 mg/ml)was utilized to im-
mobilize wolverines of both sexes and all ages.Induction time
was determined with a stopwatch and was measured from initial
injection to when the wolverine became immobile.One wolverine
was captured in a barrel trap in Prince William Sound,and was
administered mg etorphine wi th a pole syringe.
After processing,immobilized wolverines were administered an
equivalent.ml dosage of the antagonist dirpenorphine HCl
(2 mg/ml)8 either intravenously (IV)in the radial or saphenous
vein or intermuscularly (1M)in the hip area.Recovery time was
also measured with a stopwatch and consisted of the period be-
tween inj ection and regained mobi li ty.
"
5 00-99,The Lemon Co.,Inc.,Rockville,Maryland.
,Rompun,Chemagro Division of Bay Chemical Corp.,Kansas City,
Missouri.
7 Bell 206B,Bell Helicopter,Fort Worth,Texas.
37
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-
--
-
--
RESULTS AND DISCUSSION
Six 14.5-17.7 kg male and one 14.5 kg female wolverine were
darted from helicopter and one 8.6 kg female was caught in a
barrel trap.EHC1 dosages delivered from helicopter varied from
.02 -.13 mg/kg (x =.05 mg/kg,S.D.=.04)while XHC1 dosages
varied from 2.74 -2.83 mg/kg (x =2.78 mg/kg,S.D.=.05).In-
duction time ranged from 4 -19 minutes,averaging 10.0 minutes
(S.D.=6.0).The trapped wolverine was immobilized with 0.6 ml
EHC1 (.07 mg.kg)and was immobile within 7 minutes.The adult
female darted from helicopter also was not administered XHC1 but
was given 5 mg acepromazine maleate (10 mg/ml).9 Recovery time
for four wolverine which were given the antagonist IV ranged 1-9
minutes (x =4.8,S.D.=3.36)while 9 minutes were required for
two wolverines when administered 1M.No recovery time was avail-
able for the female wolverine which received the injection of
acepromazine.One wolverine recovered without the antagoni st
wi th 25 minutes following induction.All wolverines were sub-
sequently observed from fixed-wing aircraft and no adverse ef-
fects were observed.
Results of this study suggest that dosages of 0.4 mg EHC1 with 50
mg XHC1 are satisfactory for immobilizing wolverines weighing
12.6 -17.7 kg when darted from helicopter.Al though ketamine
HC1 has also been used to immobilize wolverines from helicopter,4
the EHC1/XHC1 mixture allows rapid recovery from immobilization
and therefore wolverines are not abnormally vulnerable to extreme
temperatures or hunting-trapping mortali ty.
B 00 50-50,The Lemon Co.,Inc.,Rockville,Maryland.
9 Recki tt and Colman Pharmaceutical Div.,Hull England.
38
ACKNOWLEDGMENTS
This study was supported by the Alaska Power Authority.We are
grateful to A.Franzmann and R.Tobey (both ADF&G)for their ad-
vice and cri tical review of an early draft of the manuscript.
LITERATURE CITED
Ballard l W.B.and A.W.Franzmann.In review.Comparison and
assessment of drugs used to immobilize Alaskan gray wolves
(Canis lupus)from a helicopter.J.Wildl.Dis.
BishoPI R.H.and R.A.Rausch.1974.Moose population fluctua-
tions in Alaska l 1950-1972.Nat.Can.101:559-593.
-
Hash l H.S.and M.G.Hornocker.
wi th ketamine hydrochloride.
715.
1980.Immobilizing wolverines
J.Wildl.Manage.44(3):713-
Skoog l R.O.1968.
granti)in Alaska.
Berkeley I CA.699pp.
Ecology
Ph.D.
of caribou (Rangifer tarandus
Thesis l Univ.of California l
,.,..
-
Taylor l K.P.and W.B.Ballard.1979.Moose movements and
habi tat use along the Susi tna River near Devil's Canyon.
Proc.N.Am.Moose Conf.Workshop.15:169-186.
Date received ------------------
Date accepted _
39
Appendix B.Report describing the behavior displayed by a pair
of mating wolverine.
WOLVERINE BREEDING BEHAVIOR
'"""
!
-
Breeding behavior of the wolverine (Gulo gulo)is not well de-
scribed in the literature except timing of breeding (Mehrer 1975,
Rausch and Pearson 1972)and den ecology (Pu11iainen 1968,
Myrberget 1968,Krott 1959).Described here are mating behavior
and copulation of wolverines observed from the ground on 9 June
1981.
Mating occurred on a north facing slope at 1300 m on Mt.Watana,
located in the Susi tna River Basin in southcentra1 Alaska.The
site was 9 m2 with a slope of 0-15°.Vegetation was primarily a
boulder strewn heath (Cassiope tetragona)mat surrounded by
scree.
At 1601 vocalizations ("screams")were heard which resembled the
sound of fighting cats (Felis domesticus).We approached to
wi thin 300 m of a pair of wolverines which appeared to be
fighting.The wolverines screamed and wrestled continuously from
1607 and 1609,when they began to vocalize intermittently.At
1612 the wolverines stopped vocalizing,laid down side by side
and head to head and began clinching and rolling over each other.
Between 1616 and 1617,the male walked behind the female,clasped
her back with hi s forelegs and began to copulate vigorously,
pushing the female to the ground.At 1626,the female sat up on
her front paws while the male continued to thrust actively.Both
animals fell to their right side at 1628;however,the clasp was
maintained and thrusting continued.At 1630,the female again
lay prone with the male mounted on top.Between 1630 and 1706,
the female occasionally sat up.From 1706 to 1755,the male
thrusted less frequently,but maintained his clasp and position.
No apparent change in behavior was noted when a helicopter landed
approximately 600 m north.Between 1755 and 1759,we moved to a
40
better viewing position but lost sight of the wolverines.During
that period the male withdrew and the pair left the area to-
gether.The total.duration of copulation was 102 minutes.
Tracks in the snow indicated that they had travelled together a
minimum of 2.4 km prior to and 1.6 km after copulation.
The duration and vigor of wolverine copulation is similar to that
reported by Enders (1952)and Hatler (1976)for other mustelids.
Hansson (1947)found the mean duration of 227 mink (Mustela
vison)matings to be 64 minutes.Magoun (pers.communication)
observed 3 wolverine matings lasting 12 minutes,20-30 minutes
and 54 minutes.An additional mating of 20 minutes was observed
for the latter pair.These are minimum times since the entire
copulation act was not observed.The matings observed from air-
craft occurred on 6 August/II June and 5 June,respectively,
approximately 300 km SW of Barrow/Alaska.
The apparent aggressiveness exhibited during copulation could be
dangerous for either individual.Magoun (pers.corom.)observed
agonistic behavior prior to each observed wolverine copulation.
Female wolverines,which average 30%smaller by weight than males
(Magoun 1979)/are probably exposed to greater risk.Females of
other mustelid species have died while others have scarred from
injuries incurred during mating (Enders 1952/Foott 1970/Hatler
1976).Hatler (1976)observed that male mink on fur farms had to
overpower the female even if she was physiologically receptive.
Since the risks and energy demands of wolverine mating appear to
be high,especially for the female,it is interesting to specu-
late upon the evolution of this mating behavior.Asdell (1964)
reports that most mustelids are induced ovulators and Hatler
(1976)indicates that ovulation follows copulation and/or the
stimulus of courtship battle in the mink.However/the aggres-
siveness during mustelid mating appears excessive to what would
be expected for induced ovulation to occur.Therefore,it may
41
-
-
--
....
I
1"""
I
..-
-
serve a specific function.The female invests a considerable
amount of energy during gestation,lactation,and kit rearing.
If there is intense cotnpeti tion between kits for sui table home
ranges and subsequent survival,the aggressive behavior during
breeding may constitute a component of epigamic selection.In
species exhibiting low population densities such as the wolver-
ine,the female's only cue to a male's fitness may be through the
aggressive behavior associated with courting.A male not able to
subdue a female would be less fit than one that could.It would
then be beneficial for the female to repulse males of low fitness
to maximize the perpetuation of her genes through future genera-
tions.Therefore,a future benefit of passing on her genes when
mated to the more fit male may exceed the immediate cost of phys-
ical injury imposed during breeding .
This research was supported by the Alaska Power Authority through
the Universi ty of Alaska Museum,Subtask 7.11
LITERATURE CITED
Asdell,S.A.1964.Patterns of mammalian reproduction.
Cornell Uni versi ty Press,Ithaca,N.Y.,670pp.
Enders,R.K.1952.Reproduction in the mink (Mustela vison).
Froc.Amer.Phil.Soc.,96:691-755.
Foott,J.o.1970.Nose scars in female sea otters.J.
Mammal.,51:621-622.
Hansson,A.1947.The physiology of reproduction in the mink
with special reference to delayed implanatation.Acta
Zool.,28:1-136.
The coastal
Unpubl.Ph.D..-
Hatler,D.F.1976.
British Columbia.
pp.
42
mink on Vancouver
Disser.,Univ .
Island,
of B.C.
Krott.P.1959.Demon of the north.
N.Y.,(Translated from German
159pp.
Alfred A.Knopf,New York,
by Edward Fitzgerald.),
Magoun,A.J.1979.Studies·of wolverine on'and adjacent to
NPR-A.Chap.4 in Studies of Selected Wildlife and Fish and
Their Use of Habitats on and Adj acent to NPR-A 1977-78.
U.S.Dept.of Interior.
Mehrer,C.F.1975.Gestation period in the wolverine,(Culo
guloL.)in Finland.Ann.Zoo1.Fenn.,2:338-344.
Myrberget,S.1968.Jervens ynglchi.Fauna 21:108-115.
Pulliainen,E.1968.Breeding biology of the wolverine (Culo
guloL.)in Finland.Ann.Zool.Fenn.2:338-344.
Rausch,R.A.and A.M.Pearson.1972.Notes on the wolverines
in Alaska and Yukon Terri tory.J.Wild1.Manage.,36:249-
268.
Brian Cooper,Kevin Cooper,Department of Biology,Uni versi ty of
Alaska,Fairbanks,AK 99701
Craig Gardner,Alaska Dept.of Fish and Game,Box 47,Glennallen,
AK 99588.
43
~
!
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-
'""""
--
.....
.....
--
SUSITNAHYDROELECTRIC PROJECT
PHASE I FINAL REPORT
BIG GAME STUDIES
VOLUME I I I.DALL SHEEP
Warren Ballard
John H.Westlund
Craig L.Gardner
and
Robert Tobey
ALASKA DEPARTMENT OF FISH AND GAME
Submi tted to the
Alaska Power Authori ty
March,1982
....
....
....
PREFACE
In early 1980,the Alaska Department of Fish and Game contracted with
the Alaska Power Authority to collect information useful in assessing
the impacts of the proposed Susitna Hydroelectric Project on moose,
caribou,wolf,wolverine,black bear,brown bear and Dall sheep.This
information,along with information on furbearers,small mammals,birds,
and plant ecology collected by t~e University of Alaska,is to be used by
Terrestrial Environmental Specialists,Inc.of Phoenix,New York,in
preparation of exhibits for the Alaska Power Authority's application for
a Federal Energy Regulatory Commission license to construct the project.
The studies were broken into phases which conformed to the anticipated
licensing schedule.Phase I studies,January 1,1980 to June 30,1982,
were intended to provide information needed to support a FERC license
application.If the decision is made to submit the application,studies
will continue into Phase II to provide additional information during the
anticipated 2 to 3 year period between application and final FERC approval
of the license.
Wildlife studies did not fit well into this schedule.Data collection could
not start until early spring 1980,and had to be terminated during fali 1981
to allow for analysis and report writing.(Data continued to be collected
during winter 1981-82,but could not be included in the Phase I report.)
The design of the hydroelectric project had not been determined.Little
data was available on wildlife use of the immediate project area,although
some species had been intensively studied nearby.Consequently,it was
necessary to start with fairly general studies of wildlife populations
to determine how each species used the area and identify potential impact
mechanisms.This was the thrust of the Phase I Big Game Studies.During
Phase II,we expect to narrow the focus of our studies to evaluate specific
impact mechanisms,quantify impacts and evaluate mitigation measures.
Therefore,the Final Phase I Report is not intended as a complete assessment
of the impacts of the Susitna Hydroelectric Project on big game.
The reports are organized into the following eight volumes:
Volume I.
Volume II.
Volume III.
Volume IV.
Volume V.
Volume VI.
Volume VII.
Volume VIII.
Big Game Summary Report
MOose -Downstream
MOose -Upstream
Caribou
Wolf
Black Bear and Brown Bear
Wolverine
Dall Sheep
""'"
SUMMARY
Aerial surveys were flown on 3 and 25 March,1981,to assess
winter habitat use by Dall sheep (Ovis dalli).Areas flown were
the Watana Hills count area,and the Mt.Watana-Grebe Mountain
complex.
Ground observation of the Jay Creek mineral lick located at the
2200 ft.elevation revealed heavy utilization by sheep and moose
(Alces alces).Soil samples were taken for chemical analysis.
Frequent observations of the Jay Creek mineral lick were made in
conjunction with other Susi tna studies.Sheep were seen at the
Jay Creek site on 34 of 50 occasions (68%)from 6 May to 24 June
1981.
The Watana Hills count area was surveyed on 28 July,1981,to
determine population trend and summer distribution.No sheep
were observed at the Jay Creek site .However,Dall sheep were
observed at another known mineral area in the drainage of the E.
fork of Watana Creek,approximately 7 miles to the north.
The largest number of sheep observed at the Jay Creek mineral
si te was 15 which represents 7 percent of the observed summer
population and 17 percent of the observed winter population.
Impacts of the proposed project on sheep were presented and dis-
cussed.The Watana Hills sheep population could be severly
impacted by the proposed project.Impacts on she~p in the
Watana-Grebe Mountain area and the Portage-Tsusena Creek areas
will probably be negligible although additional survey infor-
mation would be desirable to confirm this conclusion.
Plans for Phase II studies were briefly presented and discussed.
i
-
-~
TABLE OF CONTENTS
Summary
Li st of Tables
Li st of Figures
Introduction
Methods
Results and discussion
Watana Hills
Mount Watana
Portage -Tsusena Ck
Hunter Use
Potential Impacts
Plans for Phase II Studies
References.
ii
Page
i
iii
iv
1
3
4
4
12
16
16
17
18
21
-
.....
Table 1.
LIST OF TABLES
Compilation of highest yearly
completed in Watana Hills sheep
count area .
counts
trend
Page
5
-
-
"""'!
.-
i
I
Table 2.Number of Dall sheep observed in the
Watana Creek Sheep Count area of the
Susitna River Basin during a survey on 3
MarchI 1981.
Table 3.Number and age-sex classification of
sheep observed at the Jay Creek mineral
lick located in the Susitna River Basin
of Southcentral Alaska from 6 May
through 24 June l 1981.
Table 4.Number of Da11 sheep observed in the Mt.
Watana Grebe Mountain area of the
Susi tna River Basin on 25 MarchI 1981.
iii
7
10
13
Fig.1.
Fig.2.
Fig.3.
Fig.4.
LIST OF FIGURES
Dall sheep study area showing three
aerial survey areas.
Distribution of Dall sheep observed from
fixed-wing aircraft on 3 March,1981 in
the Watana Hills Count area in south-
central Alaska .
Aerial survey and distribution of Da11
sheep sighted on 22-23 July,1980 aerial
survey.
Distribution of Dal1 sheep observed from
fixed-wing aircraft on 25 March,1981 in
the Mt.Watana -Grebe Mts.Count Area
in southcentra1 Alaska.
iv
Page
2
8
14
15
....
-
-
-
INTRODUCTION
Prior to initiation of Phase I studies for the Susi tna Hydro-
electric Project,it was believed that construction and operation
of the proposed proj ect would have few adverse impacts on Dall
sheep.Identified impacts consisted primarily of harassment and
disturbance from construction activities,helicopter traffic,and
possible access routes through mountainous habitat.The original
study design was limited to determination of seasonal distribu-
tion and abundance of sheep close to the proposed impoundments.
However,reported observations of Dall sheep near the 2200 foot
elevation of Jay Creek during the first year of study suggested
the possibility.that critical habitat might be inundated by the
proposed Watana impoundment.As a result,the scope of study was
expanded to document use of the Jay Creek site.
The study area includes all drainages flowing into the Susi tna
Ri ver from Gold Creek to Kosina Creek on the south and to the
Denali Highway on the north.Survey efforts were confined to
areas of known or suspected Dall sheep habitat within this area
(Fig.1).
1
-
-
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-
-
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~o.c:en
n:s
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~n:s
~.srn
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r-In:s
CI
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c•z•CiS II:<C
4 ~0c
is 111c·U
~l-S;...
il II::I ~~101
0~=~B.!Z t !!~~~101 ~II:<C :l.....C I-1ZIUS~0~~~I-UI ~g
a::fit :cl&oI <ItB.:j ~B.
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(IIrU"--,f
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1.1 ~..,1
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III
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METHODOLOGY
Sheep observations were recruited from all Susitna study partici-
pants.Date,location,number,sex and age of all sheep observed
and subsequently reported were recorded on 1:63,360 USGS topo-
graphic maps.winter and spr.ing observations were especially
requested because they show seasonal distribution and in some
instances habi tat use.
An aerial survey was conducted with a PA-18 Super Cub,on 22 and
23 July 1980,in an effort to determine sex and age composition
and summer distribution of Dall sheep.Sixteen hours were spent
surveying sheep in 3 areas;Portage-.Tsusena,Mt.Watana,and
Watana Hills.(Fig.1).All observed sheep were identified as to
number,sex,age class and locations were plotted on 1:63,360
maps .
Sheep aerial surveys were conducted with a PA-18 Piper Super Cub
on 13 and 25 March 1981,to determine sex and age composition and
winter distribution.Approximately 6 hours were spent surveying
sheep in 2 areas;3 hours in the Watana Hills count area,and
slightly less than 3 hours in the Mt.Watana-Grebe Mountain count
area.All sheep observed were identified by sex and age class.
Their numbers and locations were marked on either 1:250,000,or
1:63,360 scale on U.S.G.S.maps.
On 9 May 1981 a.helicopter transported ADF&G biologists to the
lick near Jay Creek where Dall sheep had been observed.Ground
examination of the area was made &photographs were taken showing
use-of the area by sheep and moose.Preliminary al ti tude
measurements were taken with a hand held altimeter.Soil samples
were collected from 4 different locations,and placed in plastic
bags for future analysis.
Beginning on 13 May 1981 and continuing to 24 June 1981 aerial
observations of the area were made from a Piper Super Cub.All
3
sheep observed were counted and identified by age and sex.Their
activi ties were recorded,and their location relative to the
mineral area was plotted.
On 28 July 1981 an aerial survey of summer sheep distribution was
conducted with a PA-18 Piper Super Cub.Approximately 3 hours
were spent surveying sheep in the Watana Hills count area.All
sheep observed were identified by sex and age class.
RESULTS AND DISCUSSION
Watana Hills
The Watana Hills count area was established as a population ~rend
area for Dall sheep by ADF&G in 1967,and since that time has
been surveyed 8 times (Table 1).The July 1980 count of 174
sheep was higher than the 7 y'ear average of 163.However,if the
1974 survey of 76 sheep is eliminated,the average is 175 sheep.
Thus,the 1980 survey suggests that the population has remained
stable.
The July 1981 count of 209 sheep was the 2nd highest number of
sheep recorded for this area.The percentage of lambs was
similar to past years,and suggests that productivity and early
survival are remaining constant.The small number of legal rams
counted could reflect the rather high (13)sport harvest taken
from this area in 1980 (Tobey,pers.comm.).Although the 1981
count was relatively high it is suspected that the population has
remained stable or perhaps increased slightly.Some yearly var-
iation is expected in count data because of differences in ob-
servers and counting conditions and minor population fluc-
tuations.
4
-
-
-
Table 1.Compilation of highest yearly counts completed in Watana Hills sheep trend count
count area.
Legal %Legal %
Rams *Lambs Total Rams Lambs Surveyor
~
1950 0 Scott
1967 220 Nichols
1968 183 26.6 Nichols Aug.
1973 10 40 176 5.6 22.7 McIlroy Aug.
1974 6 18 76 7.9 23.7 Harnkess April
~'1976 4 30 130 3.1 23.0 Eide Aug.
1977 4 33 152 2.6 21.7 Spraker "July 11
1978 5 34 189 2.6 18.0 Eide July 23
1980 9 42 174 5.1 24.1 Tobey July 22
1981 2 43 209 1.0 20.6 Westlund July 28
.....
*A legal ram is defined as having a 3/4 curl or greater horn.
Beginning in 1979,a legal ram is defined as having a 7/8 curl or greater horn.
5
The winter distribution of sheep was determined during March 1981
and is presented in Table 2 and Figure 2.It is of interest that
all sheep observed were on south facing slopes l suggesting that
these areas are a very important part of Dall sheep winter range
(Gei st 1971).South facing slopes provide maximum exposure to
the winter sun l and frequently have snow depths less than ad-
j acent slopes wi th different aspects (op.cit.).
6
-
-
-
""'1
i
-
Table 2.Number of Dall sheep observed in the Watana Creek
sheep count area of the Susitna River Basin during a
survey on 3 March 1981.
Observation No.of Sheep Observation No.of Sheep
It for Fig.2 II for Fig.2...
1 2 9 16
2 13 10 7
3 5 11 1
4 5 12 2
5 3 13 2F"6 6 14 2
7 3 15 16
8 4
""'"TOTAL 87
7
Figure 2.Distribution by observation number (see Table 2)of Dall sheep
observed on 3 March 1981 in the Watana Hills count area of
southcentra1 Alaska.
8
-
-
Differences in total numbers of sheep observed between the winter
survey and the summer survey were probably the result of poor
observability due to snow cover during the March survey and/or
movement of some segments of the population from the area.
The mineral lick at Jay Creek was visited by staff biologists on
9 May 1981.Portions of the lick extend below the 2200 ft.ele-
vation.Therefore,at least a portion of the lick area will be
inundated by the Watana impoundment.Sheep usage of the area
ranged from the Jay Creek streambottom to the.top of the bluff
and for an undetermined distance away from the bluff.
Soil samples collected at the Jay Creek lick will be analyzed for
chemical content during Phase I I Studies.This analysis will
-determine the types.and concentrations of minerals and/or salts
that might be the main attractant of the area to sheep and other
ungulates.
On the day of examination (9 May),four Dall sheep were observed
actively scraping'and eating dirt from this area.This further
suggests that minerals are the main attraction.
Numbers of sheep observed from the air at the Jay Creek mineral
area during late May and June 1981 are presented in Table 3.
Classification of age classes often was not possible because
ei ther sheep were located in thick fringe vegetation or weather
conditions caused poor visibility.A total of 34 separate sheep
observations were made over a 50 day time period,starting 6 May
and ending on 24 June 1981.The largest single group observed at
the Jay Creek site was IS,on 8 May.The observation represents
approximately 7 percent of the observed Watana Hills summer popu-
lation,and approximately 17 percent of the observed Watana Hills
winter population.
--
9
Table 3.Number and age-sex classification of sheep observed at the Jay Creek Mineral
lick located in th Susitna River Basin of Southcentral Alaska from 6 May
through 24 June 1981.
Date
5/06
5/08
5/09
5/13
5/14
5/18
5/21
5/22
5/23
5/24
5/25
5/26
5/27
5/30
6/02
6/03
6/03
Time
A.M.
1645
0900
1355
1700
1145
1840
1152
1808
2225
1405
1408
Total
If Sheep
5
15
4
2
4
4
8
8
9
9
14
o
o
5
o
1
9
If
Ewes
2
1
1
2
1
1
If
Yrlgs.
2
1
1
1
2
1
10
If
Lambs
If
Rams
6
6
6
6-7
12
1
9 (?)
Comments
At edge of mountains and
flat area.
Soil samples collected.
Bedded on top near right
edge.
2 pairs standing along
right edge.
2 sheep standing along
right edge and 2 sheep
standing on 1st small
hill to m~between
lick and mountains.
Rams feeding on bushes
around edge at Lf.center.
Rams feeding on E.side of
Jay Cr.in cave on ridge.
Rams in 2 groups on E.side
of Jay Cr.
E.side of Jay Cr.2 miles
NE of lick.
Bedded on cliff 2 miles up-
stream from lick on west
side.
-
..,,
-
-
Table 3.(Cont'd)
Total t!il il il
Date Time il Sheep Ewes Yrlgs.Lambs Rams Comments
6/04 1926 0 Overcast w/heavy rains,
winds SE at 30-40.
6/05 1900 9 9 (?)E.side of creek.
6/06 2146 9 9 (?)Probably same group
as on 6/05.
6/07 2025 9 E.side.
6/08 2115 10 E.side.
6/09 7 7 W.side.
6/10 0955 4 2 2 W.side.
6/11 4 3 1 W.side.
6/12 1939 10 Mostly ewes on upstream
lick - 2 miles up.
6/13 1154 8 5 3 1 single on E.side of
lower lick.3 &2
on W.side upper lick
6/14 0933.0.....
6/15 1509 7 6 1 4 on lower lick.
2 &1 on upper lick.
6/16 1102 4 3 1 W.side upper lick.
6/17 1155 1 1 E.side upper lick.
6/19 1000 2 1 1 Ram on upper lick.
Ewe on lower lick.
6/21 1545 L4 Lower lick -W.side.
6/24 0847 7 7 Lower lick.-W.side.
11
Sheep were observed frequenting other locations adjacent to the
Jay Creek mineral site.On 23 and 25 May 1981 groups of 6 and 12
rams,respectively,were observed scraping and eating soil on the
ridge located on the east side of Jay Creek,directly opposite
the main lick area.Since only rams were observed on these 2
occasions,the observation could represent a preferential use of
certain areas by sex or age class.Also,on June 3,12, 13, 15,
16,17 and 19,sheep of different age classes were observed at an
area approximately 2 miles upstream from the main mineral area.
This area also appears to be mineralized.Further investigation
is necessary to determine the extent of mineralization and if
there is any preferential use of these areas by sex or age class.
An aerial summer distribution survey was conducted on 28 July
1981,and no sheep were observed a~the Jay Creek area.However,
a group of 10 ewes and yearlings were observed actively utilizing
a known mineral lick in the drainage of the E.Fork of Watana
Creek,approximately 7 mi les to the North of the Jay Creek site.
Mount Watana
During July 1980 only eight sheep (1 ram,7 unidentified)were
observed in the Watana Mountain-Grebe Mountain area (Fig.3).
Earlier observations in 1977 suggested that at least 34 sheep
were present on Mt.Watana.Numerous observations exist of sheep
in the Terrace Creek-Tsisi Creek area but no sheep were observed
during the 1980 survey.Either the sheep migrated from the area
or they were missed during the 1980 survey.
On 25 March 1981 a winter distribution survey was conducted in
the same area surveyed in July 1980.A total of 28 to 30 sheep
were observed (Table 4,Figure 4).If data collected during the
summer 1980 survey and this survey were representative of the
sheep population,they would indicate that sheep were migrating
into the area during winter.All sheep observations,however,
12
~,
-
.....Table 4 .Number of
Mountain
Dall sheep
area of the
observed
Susitna
in the
River
Watana-Grebe
Basin on 25
-
I
March 1981.
Observation #for Fig.3 '
1
2
3
4
5
6
13
#of Sheep
3
5
10
3-4 tracks only
3-4 tracks only
4
TOTAL 28 -30
t
N
{
Fig.3.Areas surveyed and distribution of Da1l Sheep
observed on 22-23 July 1980 aerial survey.
-
.....
..-
-
Figure 4.Distribution by observation number (see Table 4)of Da11 sheep
observed on 25 March 1981 in the Mount Watana -Grebe Mountain
count area of southcentra1 Alaska .
15
were located on the southern extreme of the count area,well away
from the impoundment and therefore,impacts of the impoundments
on these sheep populations would appear to be minor.
Portage -Tsusena Creek
A total of 72 sheep (7 legal rams,12 lambs and 54 unidentified)
was counted in the Portage Creek and Tsusena Creek drainages
during July 1980 (Fig.3).The only previous ADF&G survey in
this area was a 1977 count of 91 sheep (8 legal rams,18 lambs,
65 others).The 1977 survey included the Jack River drainage
which was not surveyed in 1980.The sheep sighted were located
fairly high up in the drainages and relatively far from the pro-
posed impoundments.Sheep may concentrate closer to the Susi tna
River in winter and may occupy habitat close to potential access
routes.No surveys were conducted in 1981.The single dis-
tribution survey would suggest that the impoundment would have
1ittle effect on these sheep populations.
Hunter Use
The 1980 harvest wi thin the Susi tna sheep study
sheep.Eight of these were considered to be trophy
horn lengths greater than 35 inches.Most of the
curred in the Watana Creek Hills.
area was 13
quality with
harvest oc-
-
...,
The 1981 sport harvest from the study area was 2 sheep,also
taken from the Watana Hills area.This small harvest could in-
dicate a reduced number of available legal rams,or simply less
hunting pressure in the area.
16
-
-
Potential Impacts
At the time this study was designed it was assumed that the only
significant impact of the Susitna Hydorelectric Project on Dall
sheep would be from disturbance from construction activities,
helicopter traffic,etc.Such impacts could be moderated by
avoiding areas used by sheep or scheduling activities at seasons
when sheep use of an area was reduced.However,sightings of
sheep along Jay Creek indicate a possibility of direct loss of
habitat.
The Portage -Tsusena Creek sheep are likely to be impacted only
by disturbance.With adequate data on seasonal distribution
serious disturbance probably can be avoided.However,the pro-
posed borrow pit and the corresponding roads to be located on
upper Tsusena Creek could potentially cause a significant shift
in sheep distribution and a loss of critical winter range.The
status of the Mount Watana population is less clear.Limited
data indicate that sheep occupied habitat close to the proposed
Watana impoundment where disturbance and perhaps even habitat
loss could be problems.This distribution was not confirmed by
the July 1980 or the single winter survey .More survey infor-
mati on is needed.
The Watana Hills sheep population appears to be the most vulner-
able to severe impact from the proposed Watana impoundment.·Its
close proximity to the impoundment makes the population extremely
vulnerable to di sturbance from construction and transportation
activities which could alter behavior,affect lambing success and
force abandonment of the Jay Creek mineral lick.
The Watana Hills sheep population appears to be isolated from
other sheep populations.Thus,recovery of this population,if
severly impacted by short term construction activities,could be
slow relative to other sheep populations.
17
A portion of the Jay Creek mineral lick will be inundated by the
Watana impoundment.The importance of thi s lick to the sheep
population is not known but our preliminary observations suggest
that a significant portion of the sheep population utilize the
area during late May and June.Sheep also use the area during
other months of the year but adequate documentation does not
exist.If sheep utilize the mineral lick similarly to those
recorded elsewhere in Alaska (Heimer 1973),significant portions
of the Watana Hills sheep population could be influenced,par-
ticularly if late spring snow depths are influenced by the im-
poundment.Another lick 7 miles to the north could provide an
alternative source of mineralization for the sheep utilizing the
Jay Creek lick,but the chemical content of both licks is unknown
at this time.Also the season and type of use at the alternative
lick could be a significant factor dictating whether additional
use could or would be tolerated.Additionally I if only certain
sex or age classes traditionally utilize the licks,different
segments of the sheep population may not be aware of the exis-
tence of alternative areas (Geist 1971).
The scope of the Phase I sheep studies was not adequate to assess
the potential impacts of the project on sheep.Considerable ex-
pansion of study efforts will be required during Phase I I.
Plans for Phase I I Studies
TITLE
Dall sheep movements and habitat use patterns in relation to
mineral lick habitat that will be impacted by the proposed
Susi tna Hydroelectric Proj ect.
OBJECTIVES
To determine the size and sex and age composition of subpopu-
lations of Dall sheep utilizing the Jay Creek mineral lick.
18
-
-
To determine the time of travel and travel routes of those popu-
lations to and from the lick si te.
To determine the timing
populations on habitat
hydroelectric project.
and degree of dependence of sheep sub-
that will be impacted by the Susi tna
--
To identify habitat critical to sheep subpopulations in the
vicini ty of the proposed impact area.
To intensively assess winter distribution of three populations to
determine possible impact by proposed borrow pits and access
routes.
PROCEDURE
1)Approximately 25 animals will be captured and fitted with
radio-collars and visible ear tags.Most of these will be
captured during late spring when they are on their winter
range.Standard helicopter capture techniques will be
utilized.The sex and age ratio of animals captured will
approximate the ratio observed in the population.
.-
-
-
2)
3)
The remaining animals to be fitted with radio-collars not
captured by helicopter wi 11 be captured at the lick si te,
with the use of a cannon net.Procedures will follow those
used by Heimer.Capturing animals wi th this method will
allow personnel to mark individuals in the ratio at which
they visit the lick area.Animals captured but not fitted
with radio-collars will be marked with high visibility ear
tags and visual collars.
Aerial location and observation of radio-collared animals
will occur twice a month during spring and fall,and once a
19
4)
5)
6)
month during the remainder of the year.Information to be
gathered during these flights will include:number,sex and
age composition,location,aspect of the location,altitude,
snow depth,and vegetati on type.
Seasonal range use and distribution will be determined by
radio-collar locations,and visual ground observation of
tagged animals.Ground observations will be attempted
during the summer months.
Critical south slope habitat will be identified during
winter months.Snow conditions will be monitored,and their
effect on sheep noted.
A literature search will be conducted to locate information
regarding micro-climatic changes involving large bodies of
water.Climatic changes producing greater snow depths could
be detrimental to the sheep populations,if it falls on
critical south slopes.
-
7)Additional sheep will be marked by spraying from fixed-wing
aircraft (Nichols pers.comm.).
8)Ground observations will be conducted at both the Jay Creek
and Watana Creek mineral licks to determine use by number,
sex and age of sheep.Exchange of sheep between the two
licks will be determined by observations of dyed and radio-
collared animals.
9)Chemical analyses will be performed from soil samples col-
lected at both lick si tes.
10)Aeri a1 surveys wi 11 be conduc ted to moni tor winter di s-
tribution and abundance of the Tsusena-Portage Creek sheep.
20
-.
r
"..,
REFERENCES
Alaska Dept.
habitat.
563 maps.
of Fish and Game.
Alaska Dept.Fish
1973.Alaska's Wildlife and
and Game,Anchorage.144pp +
"'"'
-
-
-I
Geist,V.1971.Mountain sheep:a study on behavior and evo-
lution.Univ.of Chicago.383p.
Heimer,W.E.1973.Dall sheep movements and mineral lick use.
Alaska Fed.Aid Wildl.Rest.Final Rep.Juneau.
21