FINAL REPORT

he status, distribution, and management of mountain
goats in the Greater Yellowstone Ecosystem

Dr. John VV. Laundre'

Department of Biological Sciences, Idaho State University

Pocatello, ID 83209

NTS Order # PX 1200-8-0828

Submitted: 9/30/90

Covering the time: 5/88 - 8/90

Digitized by the Internet Archive
in 2013

http://archive.org/details/statusdistributi369laun

FINAL REPORT

The status, distribution, and management of mountain
goats in the Greater Yellowstone Ecosystem

Dr. John W. Laundre'

Department of Biological Sciences

Idaho State University

Pocatello, ID 83209

NPS Order # PX 1200-8-0828

Submitted
September 1990

Covering the time: 5/88 ■- 9/90

ABSTRACT

Mountain goats (Oreamnos americanus) are not thought to be historic natives to the
Greater Yellowstone Ecosystem. They occurred in the area >10,000 B.P. but all evidence
indicates they were extirpated from the area by the time Europeans arrived there. The Idaho
Department of Fish and Game and the Montana Department of Fish, Wildlife, and Parks
introduced goats into the area in the mid 1900's. Goats have expanded in numbers and range
and are occasionally seen within Yellowstone and Grand Teton National Parks. Their
presence in the Parks might negatively impact native plants and animals there. This study
assessed the current distribution of mountain goats and their potential impact on fauna and
flora of the Parks. The current distribution of mountain goats in the Greater Yellowstone
Ecosystem was determined by consulting area resource managers, perusing sighting records,
and conducting field surveys. The potential impact of goats on the fauna and flora of
Yellowstone and Grand Teton Parks was assessed by compiling all available information on
mountain goat behavior and ecology.

Mountain goat distribution within the Greater Yellowstone Ecosystem has not changed
significantly from previously reported accounts. If goats do colonize either Park, low and
high population levels of 95 and 500 for Yellowstone and 160 and 500 for Grand Teton Parks
were estimated. Based on existing literature, little impact of goats on vegetation and the
physical environment is anticipated in either Park. The main wildlife species that goats may
impact would be bighorn sheep (Ovis canadensis). General food habits and habitat
requirements of mountain goats and bighorn sheep overlap in a broad sense. However, in
sympatry, investigators have found minimal overlap in specific foods used and habitat
selected. At low population estimates of goats, no negative impact on sheep in Yellowstone
is anticipated. In Grand Teton Park, even low numbers of goats may impact sheep because
of constricted sheep winter range. Goats are expected to negatively impact sheep in both
Parks at high density estimates. At this time, it is difficult to predict future population trends
of goats and their total impact on the two Parks.

If the National Park Service classifies goats as exotic to the Greater Yellowstone
Ecosystem, Park personnel will have to develop a management plan for them. Three
management alternatives are presented: No action, limited control of mountain goats, and
total elimination of goats within Park boundaries. Of the three alternatives, it was
recommended no action be taken at this time. However, a multi-option plan should be
formulated to respond to whatever changes in goat numbers and distribution occur in the
future.

ACKNOWLEDGMENTS

This work was funded by a grant from the National Park Service through the
University of Wyoming-National Park Service Research Center (FX 1200-8-0828), K. Diem and
M. Boyce, Directors. Acknowledgements are giving to the following persons for their help
in compiling the data reported herein or in reviewing the final draft. K. Alt, G. Bowser, E.
Hadly-Barnosky S. Consolo-Murphy, R. Gale, J. Haden, J. Hanna, D. Houston, G. Joslin, M.
Maj, M. Meagher, S. Miller, D. Reed, J. Rosco, S. Smith, R. Schiller, M. Shroder, B. Shuster,
F. Singer, D. Stradly, G. Taylor, J. Varley, B. Wood. These individuals represent a variety of
state and federal agencies including Yellowstone National Park, Grand Teton National Park,
Olympic National Park, Idaho Department of Fish and Game, Wyoming Department of
Game and Fish, Montana Department of Fish, Wildlife, and Parks, Targhee National Forest,
Caribou National Forest, Shoshone National Forest, Bridger-Teton National Forest, Gallatin
National Forest, Red Rock Lakes National Wildlife Refuge, and the U.S. Department of Land
Management. With these many persons supplying varying amounts of information, I likely
missed a few individuals who contributed to my efforts, to them, I apologize. Lastly, I thank
all the researchers referenced in this report for their countless hours of field work, without
which this report would not have been possible.

TABLE OF CONTENTS

Abstract

Acknowledgments

Table of Contents

List of Figures

List of Tables v

Introduction 1

Methods 2

Current Status of Mountain Goats 2

Impact of Goat Colonization 2

Impact on Park habitat 2

Impact on Bighorn sheep 4

Management Options and Final Recommendations 5

Results and Discussion 5

Current Status and Distribution 5

Yellowstone National Park 7

Grand Teton National Park 9

Conclusions 12

Impact of Goat Colonization 13

Impact on Park habitat 13

Impact on Bighorn sheep 25

Historic and Prehistoric presence of goats 37

Management Alternatives 41

No action 41

Selective control of goats 43

Elimination of goats 45

Other alternatives '. 46

Removal methods 47

Recommendations 48

Literature Cited 52

in

LIST OF FIGURES

1. Current distribution of mountain goats in Yellowstone Park 6

2. Juxtaposition of native and introduced goats near northwest corner of YNP 8

3. Current distribution of mountain goats in Grand Teton Park 10

4. Location of vegetation sample points on Wolverine Peak, YNP 20

5. Resource overlap indices for goat and sheep diets 30

6. Resource overlap indices for habitat use by goats and sheep 34

7. Location of known paleontological remains of mountain goats 39

8. Flow diagram for selecting options regarding mountain goat management 51

IV

LIST OF TABLES

1. List of mountain goat sightings in and near Yellowstone National i ark 7

2. List of mountain goat sightings in and near Grand Teton National Park 11

3. Alpine plants found in YNP and GTNP 16

4. Percent plant cover for various areas in YNP and GTNP 19

5. Summary of general food habits of mountain goats 21

6. Summary of specific plants eaten by goats 23

7. Summary of general food habits of bighorn sheep 26

8. Summary of specific plants eaten by bighorn sheep 27

9. Comparison of specific preferred plant genera for goats and sheep 29

10. Summary of feeding trials for bighorn sheep and mountain goats 30

11. Specific food habits of sympatric goats and sheep in Montana 31

12. Habitat use of sympatric goats and sheep in Montana 33

13. Selection of physical habitat characteristics by goats and sheep 35

14. Winter population estimates (1903-81) for YNP 36

15. Winter population estimates for specific areas in YNP 37

16. Comparison of capture and control techniques for goats 45

17. Impacts of proposed management plans on YNP and GTNP 49

INTRODUCTION

Mountain goats (Oreamnos americanus) are indigenous to western North America but in
the United States were historically limited to northern Idaho, northwestern Montana, and
western Washington (Guenzel 1980). Since the 1920's state wildlife agencies in the
northwestern U.S. have introduced goats into previously uninhabited regions. Consequently
goats are now found in areas where they historically did not occur.

These range expansions have increased recreation opportunities for hunting and wildlife
watching and have been popular with the American public. Ecologically, goats in these areas
are exotic species. Exotic species usually have a negative impact on native fauna and flora
in an ecosystem and either cause reductions in densities or extirpation of native populations.

Although there is some debate (Lyman 1988), it appears goats historically did not occur
on the Olympic Peninsula of Washington. They were introduced between 1925-1929
(Houston et al. 1986). From the 11 or 12 animals introduced (Anonymous 1987a), the
population has grown to over 1,000 animal (Houston et al. 1986) and has profoundly affected
native fauna and flora of the Park. Native species of plants that evolved in the absence of
mountain goats are now threatened from overgrazing (Pike 1981) and dust wallowing activity
of goats (Anonymous 1987a). The impact of goats is compounded in Olympic Park because
goats are protected from human hunting and therefore occur in higher densities than in
exploited populations (Kuck 1977; Swenson 1985).

Mountain goats are also not thought to be historic natives in the Greater Yellowstone
Ecosystem (Skinner 1926). Animals were released at several sites in National Forests
surrounding Yellowstone National Park (YNP) and Grand Teton National Park (GTNP) in
the 1950's and 60's. The introductions have been successful and goat populations are
increasing. Goats are now reported in many mountain ranges surrounding the Parks and
occasional sightings are reported within both Parks.

If mountain goats were not part of the original fauna of the Yellowstone Ecosystem, their
introduction outside and possible movement inside Yellowstone and Grand Teton National
Parks presents practical and philosophical problems. Based on experiences in Olympic
National Park, the immigration introduction of goats into Yellowstone and Grand Teton
Parks could threaten native alpine habitat and certain wildlife species such as bighorn sheep
(Ovis canadensis). The presence of mountain goats in the Parks could also violate Park System
mandates to preserve original faunal and floral communities.

Mountain goats could eventually colonize Yellowstone and Grand Teton National Parks.
Their potential impacts on native fauna and flora need to be assessed and a management
plan needs to be formulated to avoid crisis management after goats become established.
Sufficient information on the ecology of goats is available to assess their potential impact on
Park ecosystems. This assessment can be used to develop a management plan before
colonization occurs. This planning would allow Park personnel sufficient time to consider
all management options and implement the management strategy selected.

The general objective of this project was to conduct an impact assessment of mountain
goats on the Yellowstone and Grand Teton National Park ecosystems and develop
management alternatives for Park personnel.

There are three specific objectives for this study:

1) Determine current population status of mountain goats
in the Greater Yellowstone Ecosystem.

2) Assess potential impacts of mountain goats on floral
and faunaJ species of the Parks.

3) Based on findings of the first two steps, formulate
different management scenarios and assess their
feasibility and anticipated impacts.

METHODS
CURRENT STATUS OF MOUNTAIN GOATS

Data on the current distribution and status of mountain goats are necessary to determine
likely colonization sites and probable timing of those colonizations. Park managers then can
anticipate where and how soon management strategies will have to be implemented.

To assess the current status of mountain goats, I perused various sources of information.
All of the mountain goat populations surrounding the Parks are from transplant efforts by
state wildlife agencies from Idaho and Montana. These agencies maintain information on the
status and distribution of the goats under their jurisdiction in the form of published
manuscripts, internal reports, and personal knowledge. Wildlife biologists employed by the
National Forests on which goats live also have data on goats. Park personnel maintain
records of goat sightings in Yellowstone and Grand Teton National Parks. I contacted all
these agencies and compiled any information they had.

In addition to compiling existing information on goat sightings, I conducted ground and
air searches in areas where sightings were most prevalent in Yellowstone Park. I used all this
information to update the current distribution map for goats (Anonymous 1987b).

IMPACT OF GOAT COLONIZATION

Impact of mountain goat colonization on Park habitat.

Mountain goats primarily graze on grass and forb species in alpine meadows (Saunders
1955; Hibbs 1967; Peck 1972; Johnson et al. 1978; Adams and Bailey 1983; Dailey et al. 1984).
I assessed their impact on the alpine habitat in the Parks by:

1) Determining location and calculating size of habitat
likely to be colonized by mountain goats.

2) Quantifying habitat composition of potential goat range
and establishing permanent vegetation reference plots.

3) Reviewing current literature on mountain goat food
preferences.

4) Determining effect of goat populations on alpine
habitat in adjacent National Forests.

Location and size of impact flreas:-From available habitat maps, the total amount of
alpine /subalpine habitat in the Parks was estimated. These areas represent the maximum
amount of habitat that might be colonized and affected by goats. Estimates of the number
of goats likely to inhabit appropriate areas were based on population density estimates
reported in the literature.

Habitat composition of impact flreosr-Plant species lists of areas likely to be used by goats
were compiled from existing literature. Thirty permanent vegetation reference plots in areas
considered most likely to be colonized by goats were established. Plots were marked with
30 cm lengths of iron rod driven in the ground to a depth of approximately 20 cm. Brass
tags imprinted with the area and plot numbers were affixed to the rods with stainless steel
wire and rocks were piled around the exposed rod and tag. In the sparse, low vegetation of
these areas, the rock piles are distinctive enough to facilitate future relocation of the plots.
Photographic records (Houston 1982) were made of reference points and percent plant cover
was estimated from the photographs.

Food preferences of goafs:-Mountain goats are indigenous to many areas with faunal and
floral compositions similar to the Greater Yellowstone Ecosystem. Various investigators have
studied food preferences of mountain goats in many of these areas (Anderson 1940; Casebeer
1948; Brandborg 1955; Saunders 1955; Hibbs 1967; Peck 1972; Adams and Bailey 1983;
Campbell and Johnson 1983). I used the data from these and other studies to compile a list
of food preferences for mountain goats. I compared these food preferences with plant species
lists for the Parks to predict the impact of goats on floral makeup of those areas.

Impact of goats on surrounding Forest Service Lands.-Goats currently live in alpine habitat
adjacent to the Parks. Personnel from local state and federal agencies were consulted
concerning the impact of goats on these areas. Additionally, selected areas were visited and
qualitative and quantitative assessments of habitat composition of these areas were made.
Quantitative measurements were made of percent cover of randomly selected photo points.
The point frame method described by Floyd and Anderson (1982) was used for these
measurements. Based on the information and data collected, changes in habitat in impact
areas within the Parks were predicted for low and high goat densities.

Impact of mountain goats on bighorn sheep.

The most likely animal species to be affected by mountain goats is bighorn sheep (Adams
et al. 1982b) because colonization by mountain goats will likely be within existing sheep
range. I assessed anticipated impacts of goats on sheep by:

1) Calculating resource overlap of food and habitat preferences
of goats and sheep.

2) Reviewing current literature on mountain goat and
bighorn sheep interactions.

3) Analyzing population trends of goats and sheep in
National Forests surrounding Yellowstone and Grand
Teton National Parks.

Resource overlap— Food and habitat preferences of sheep and goats were determined from
the literature. Resource overlap indices (O) were calculated from these data with equation
1 (Lawlor 1980).

(1)

Oik = lptjPkj/[2(pij)2'2(pkj)2l1/2
Where: pt: and pk: are the proportions of resource type ; used by species i and k.

Goat-sheep interactions.—Goats and sheep co-occur in a variety of areas in the northwest.
Data exist on several aspects of their relationship (R.W. Thompson 1981; Adams et al. 1982b;
Johnson 1983; Dailey et al. 1984). These studies were reviewed to assess impacts goats may
have on sheep in the Parks.

Population trends in surrounding National Foresta-Sheep and goats presently co-occur in
areas adjacent to the Parks. Records on the population status of bighorn sheep and goats are
available from the literature and wildlife agencies. This information was examined for trends
in sheep densities relative to introduction and establishment of goat populations.

MANAGEMENT OPTIONS AND FINAL RECOMMENDATIONS

After objectives 1 and 2 were completed, three management strategies were developed.
They were: 1) no action, let goats become part of faunal component of the Parks, 2) control
goats at certain densities within the Parks, and 3) removal of all goats that enter the Parks.
The viability of each option was assessed based on:

1) Feasibility of implementation: Cost and logistics in

meeting management goals.

2) Implications to Park policy: Compatibility of

management plan with Park
philosophy.

3) Public acceptance: Anticipated reaction

of public to management
plan.

4) Environmental impacts: Impact of management plan

on mountain goats and

native plants and animals

in the Greater Yellowstone Ecosystem.

Information on these criteria were collected from existing literature and from consulting
with Park personnel. The strategies were then prioritized and management recommendations
made to Park Service personnel of both Parks.

RESULTS AND DISCUSSION
CURRENT DISTRIBUTION AND STATUS

Original transplants of mountain goats within the Greater Yellowstone Ecosystem were
made in Idaho and Montana. Personnel of the Montana Department of Fish, Wildlife, and
Parks introduced 55 goats into various ranges northwest of Yellowstone Park between 1947-
59 and 72 goats into the Absaroka/Beartooth mountains between 1942 and 1958 (Unpublished
data, Montana Department of Fish, Wildlife and Parks). Twelve goats were introduced by
the Idaho Department of Fish and Game into the Palisades /Black Canyon area near Swan
Valley, Idaho in 1969-71 (Hayden 1984).

Goats have increased in number from these initial transplants. The original 23 goats
transplanted near Pine Creek in the Absaroka Mountains had increased to approximately 100
animals by 1983 (Swenson 1985). By 1983, the original population of 12 goats in the Palisades
area had increased to approximately 150 animals (Hayden 1984). In the Absaroka population,
the kid:100 adult goat ratio reached a high of 60 in 1966 (Swenson 1985). The Palisades

population had a similar ratio of 75 kids:100 adults in 1983. These kid:adult ratios indicate
a rapidly increasing population and are considered high compared to native populations
(Hayden 1984). Data from other transplanted populations indicate such rapid increases in
numbers after a transplant are common (Guenzel 1980). The main effect of the increase in
goat numbers has been expansions of ranges of the goats (Fig. 1) (Anonymous 1987b).

Figure 1. Current (1987) distribution of mountain goats in National Forests adjacent to Yellowstone National Park (Anonymous
1987b) and recent sightings of goats reported to various resource management agencies.

• Goat Sightings
£ Current Range

Kilometers
6 10 20 30

Yellowstone National Park

Four visits were made to Yellowstone National Park in 1988. On the first visit (15-16
June 1988), Park personnel were consulted and records were examined for information on
mountain goats in and near Yellowstone Park. This information was used to identify areas
where goats most likely occurred. During the second visit (19-21 June 1988), the Mt. Holmes
and Wolverine Peak areas were searched for goats. No goats were sighted on Mt. Holmes
but 8-10 goats, including 2 kids, were sighted on and near Wolverine Peak. On 12-14 July
1988 an aerial survey of the north half of the Park was made. All likely goat habitat in the
northwest, northcentral and northeast sections of the Park was searched. Goats were again
sighted in the Wolverine Peak area but not in other areas. Because of a recent reported goat
sighting in the Hellroaring Mountain area, a ground search was conducted there; no goats

Tabic 1. List of mountain goat sightings reported for Yellowstone National Park and adjacent National Forests.

Date of Observation

Location

Number

Sex/ age

20

Jul

1965

Bighorn Peak

7/ Ad

29

Jun

1966

Meridian Peak

?/Ad

2

Jul

1969

Bighorn Peak

?/Ad

Jul

1969

Sepulcher Mm.1

13-15

?/?

Sep

1972

Wolverine Peak

M/Ad

6

Sep

1978

Bliss Pass

?/Ad

9

Jul

1981

Gallatin River

?/Ad

5

Sep

1982

Wolverine Peak

?/Ad

10

Sep

1982

Sunset Peak

7/ Ad

10

Sep

1982

Wolverine Peak

?/Ad

8

Sep

1983

Wolverine Peak

1.2

F/Ad-?/kid

16

Jul

1984

Barronelte Peak

M/Ad

Jun

1985

Specimen Cr.

?/Ad

20

Aug

1985

Hellroaring Cr.

?/Ad

Aug

1985

Sunset Peak

?/Ad

19

Oct

1985

Wolverine Peak

?/Ad

1

Jan

1986

Bliss Pass

1.2

F/Ad-?/kids

12

Apr

1986

lshawoon Hills2

M/Ad

17

Apr

1986

Ishawoon Hills

M/Ad

18

Apr

1986

Bcem Gulch2

?/?

22

Apr

1986

Ishawoon Hills2

?/?

17

May

1986

Ishawoon Hills2

M/Ad

24

May

1986

lshawoon Hills2

M/Ad

31

Jul

1986

Bliss Pass

?/Ad

11

Aug

1986

Cutoff Mm.

?/Ad

19

Aug

1986

Hardpan Creek

?/?

11

Sep

1986

Irish Rock2

M/Ad

21

Aug

1987

Mtn. Everts

I ?/Ad

31

Aug

1987

Dome Mtn.

2

?/Ad

4

Sep.

1987

Dome Mtn.

2

?/Ad

22

Oct

1987

Electric Peak

2

?/Ad

20

Jun

1988

Wolverine Peak

8,2

?/ Ad-?/ kids

30

Oct

1988

Abiathar Peak

1

?/Ad

27

Oct

1988

Wolverine Peak

4.2

2M&2F/Ad-?/kids

'Likely a band of bighorn sheep

•Outside established range on adjacent National Forests

were found. On 26-28 October 1988, Wolverine Peak was revisited in conjunction with
collecting habitat data in the area. At that time, four adults (2 male and 2 female) and 2 kids
were seen on the summit of Wolverine Peak. Sex determination of adult animals was based
on criteria outlined by Smith (1988).

Table 1 and Figure 1 present the reported sightings of mountain goats for Yellowstone
National Park and adjacent National Forests. Sightings in most areas are sporadic and the
reliability of the sightings varies. All sightings were within current bighorn sheep range and
inexperienced individuals can mistake bighorn ewes for mountain goats. Although sightings

Figure 2. Distribution of mountain goats near the extreme northwest corner of Yellowstone Park relative to native populations to
the west. The two sightings indicated were in the Gravelly Mountain range north of Red Rock Lakes Wildlife Refuge and the
Centennial Mountains south of the refuge.

O Native

*# Introduced

in some areas are more consistent, there is no evidence goats have actually become
established in most areas. Based on the aerial survey, the field surveys, and reports, goats
are currently established only in the Wolverine Peak/ Sunset Peak area in the northeast corner
of the Park. Adult goats with young were consistently seen in this region throughout the
summer and fall. In the other areas, animals seem to be transient. Whether goats will
become established in other areas where they have been reported is unknown.

There is some uncertainty as to the origin of mountain goats sighted in the northwest
corner of the Park (Fig. 1). It is assumed the goats being reported are emigrants from
introduced core populations to the northwest. However, it is possible goats may be
immigrating into the Park from existing native populations to the west along the Montana-
Idaho border. These populations are found within 30 km west of Monida Pass (Fig. 2) but
may be extending their range. There has been one confirmed sighting of a goat in the
Gravelly Range north of the Red Rock Lakes Refuge and possible sightings in the Centennial
mountains to the south (Fig. 2). These animals may have come from the western populations
as there are no significant barriers to movement of goats to the east; the lowest pass is 1860
m (Fig. 2). It is generally thought that goats are relatively poor dispersers (Stevens 1983) and
that it is unlikely that they would colonize areas to the east. However, the relatively rapid
and widespread dispersal of introduced goats from all the release points north of Yellowstone
Park, including into the Park, tends to refute this hypothesis. The close juxtaposition of
native and introduced populations and the conflicting evidence of their dispersing ability
puts the origin of any dispersers in doubt. It may become critical to determine if goats
moving into the northwest corner of the Park are descendants of introduced stock to the
north or are from native stock to the west. Animals moving into the Park from native
populations, could represent a "natural" extension of their range; goats from introduced
populations might be considered exotic. DNA fingerprinting would be necessary to
determine origins of goats moving into the Park in the northwest corner. However, taking
such action would depend on the historic/ prehistoric status of mountain goats in the
Yellowstone Ecosystem. This topic will be discussed later.

Grand Teton National Park

Two visits to Grand Teton National Park and vicinity were made during this study. The
first visit (14 July 1988) was to consult with Park personnel and review reports of goat
sightings. A summary of those sightings inside and near the Park are presented in Table 2
and Figure 3. As with Yellowstone Park, all sightings in Grand Teton Park were within or
near existing bighorn sheep range (Fig. 3) and seem to be of transient individuals. When
checking on sighting reports, Park personnel have not consistently relocated animals and
there have been no sightings of young.

South of Grand Teton National Park, sightings have been more frequent and consistent
(Table 2). Most of the sightings have been from the Taylor Mountain region. Hikers have
reported seeing goats in the Taylor Mountain area yearly since 1981, including at least one
sighting of a yearling. During this study, I sighted three adult goats on the southeast side
of Taylor Mountain on 30 October 1988. Thus, there seems to be a small but persistent
population of goats in this area. It is unknown why the population has not expanded

Figure 3. Current (1987) distribution of mountain goats in National Forests adjacent to Grand Teton National Park (Anonymous
1987b) and recent sightings of goats reported to various resource management agencies. The current distribution of bighorn sheep
is also indicated.

• Goat Sightings
% Goat Range
ij (j Sheep Range

0 10 20 30

10

Tabic X Sightings of mountain goala in and adjacent to Grand Teton National Park.

Dale

Location

Number

Ak-v'So

Aug

1977

Teton Pass

16

Jul

1979

Game Ck. Divide

25

Aug

1979

Paintbrush Canyon

28

Aug

1979

Holly Lake

29

Aug

1979

House Top Mtn.

1

Sep

1979

Amphitheater Lake

3

Sep

1979

Paintbrush Divide

23

May

1980

Death Canyon

Jul

1980

Teewinol area

10

Aug

1980

Owl Peak

1

Sep

1980

Fox Or. Pass

24

Sep

1980

Teton Canyon

25

Sep

1980

Forellen Peak

29

Sep

1980

Moose Basin Divide

24

Oct

1980

Treasure Mtn.

1

Nov

1980

CoalCk.

12

Jul

1981

Teton Pass

Aug

1981

Housetop Mtn.

1

Sep

1981

Taylor Mtn.

22

Jul

1982

Taylor Ck

20

Aug

1982

Fossil Mtn. Pass

18

Sep

1982

Taylor Mtn.

26

Oct

1982

Taylor Mtn.

12

Jul

1983

Observation Peak

24

Sep

1983

Long Spring Canyon

1

Oct

1983

South Fork Ck

14

Oct

1983

Taylor Mtn.

16

Oct

1983

Taylor Mtn.

23

Sep

1983

Long Spring Canyon

14

Sep

1985

Ferry Peak

17

Sep

1985

Garden Canyon

20

Sep

1985

Burnt Timber Canyon

21

Jul

1986

Taylor Mtn.

24

Aug

1986

Burnt Timber Canyon

3

Sep

1986

North Fork Ck

14

Sep

1986

Ferry Peak

15

Oct

1986

North Fork Ck

16

Oct

1986

Taylor Mtn.

26

Jul

1987

Treasure Mtn.

7

Aug

1987

Death Canyon

15

Sep

1987

Taylor Mtn.

12

Oct

1987

Mud Peak

27

Jun

1988

Taylor Mtn.

30

Oct

1988

Taylor Mtn.

?/Ad-?/Juv

M/Ad

M/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

M/Ad

?/Ad

?/Ad

M/Ad

M/Ad

?/Ad

?/Ad

?/Ad

F/Ad

?/Ad

?/Ad-?/Juv.

?/Ad

?/?

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

?/Ad

F/Ad

F/Ad

?/Ad

?/Ad

?/Ad

M/Ad

?/Ad

?/Ad

beyond the few animals that are periodically seen. There are ample mountain peaks that
appear suitable for goats. Possibly the area lacks adequate winter habitat. This aspect will
be addressed later.

11

Conclusions

Ranges of goat populations have not changed significantly from 1987 (Anonymous
1987b). The only place goats are firmly established within Park boundaries is the northeast
corner of Yellowstone Park. These animals are extensions of a well established population
in the Absaroka/Beartooth Mountains and move in and out of the Park on a daily basis.
From these established population centers, goats are venturing into various interior areas in
both Parks. Reports of these visits have increased in recent years but may be a result of
increased use of back country areas by hikers rather than an increase in the number of goats
visiting.

Field evidence indicates these vagrants are most likely billies (Stevens and Driver 1978;
Adams et al. 1982a; Stevens 1983) and such sojourns are scouting trips by adult males for
females or dispersal from home areas by young billies. Adult males looking for females
move into an area and when no females found, move back out again. These "probe
movements" (Stevens 1983) could explain the one or two ephemeral sightings of an animal
in an area. Dispersing subadults might move into an area and remain a year or more and
eventually leave the area or die. Such "wandering movements" (Stevens 1983) could account
for the persistent sightings of one or two animals in an area. Based on sighting records, such
trips have been occurring in both Parks for at least the last 10-15 years.

It is unclear why goat populations have yet to become established in the Parks.
Perhaps goat population densities outside the Parks are not high enough to force sufficient
numbers of animals to pioneer the new areas. The Absaroka population studied by Swenson
(1985) reached a peak in the early 1970' s, declined slightly by 1978 and then stabilized by
1983. Kid:adult ratios in the 1980's was approximately 20:100 compared to 60:100 during the
expansion years. The population density of the Palisades population in 1986 had increased
to 230 animals with approximately 46 kids. However, in 1988 the Idaho Fish and Game
found a population of 214 with approximately 52 kids. Thus, between 1986 and 1988, the
population stabilized with kid production lowering to 32 kids:100 adults compared to 75:100
for 1983 (Hayden 1984). The sigmoid growth and declining kid:adult ratios were found in
other transplanted populations (Guenzel 1980; R.W. Thompson 1981) and may be typical of
such populations (Caughley 1970). If populations at the initial release areas are stabilizing
because of low kid production, there would be fewer numbers of animals that might emigrate
to surrounding ranges.

There are several factors that may contribute to stabilization of goat numbers. All
established populations of goats outside the Parks are currently hunted* Kuck (1977) and
Houston and Stevens (1988) found goat populations were susceptible to overharvest.
Swenson (1985) also found a negative correlation between population trends in the Absaroka
goats and harvest rates. Reproduction rates can also be negatively correlated with snow
depth (Bailey and Johnson 1977; R.W. Thompson 1981; Adams and Bailey 1982; Swenson
1985) and population density (Swenson 1985). These three factors, harvest, snow depth, and
population density, operating in synchrony could stabilize a population and slow the rate of
colonization of new areas of appropriate habitat. These factors would only slow, not
eliminate, colonization. Goat populations still might eventually become established in the
Parks in the future.

Another reason goats may not be established in the Parks is because of insufficient
winter habitat. Winter conditions in many of the areas where goats have been sighted may

12

be too harsh for survival of pioneering individuals. Swenson (1985), Bailey and Johnson
(1977), and Adams and Bailey (1982) found low kidradult ratios when snow depth on 1 May
exceeded 200 cm. Snowfall between 1700 and 2500 m in the northern range of Yellowstone
averages 378 cm (Oldemeyer et al. 1971). In the northeast corner of Yellowstone and adjacent
mountains, snow depth varies from 119 to 230 cm (Pallister 1974; Stewart 1975; Martin 1985;
Swenson 1985). Snow pack in the Grand Teton area can be in excess of 240 cm (Whitfield
1983). These snow depths could affect kid and adult survival.

There are 200-300+ bighorn sheep in Yellowstone Park (M. Meagher, Personal
Communication) and historically there were good populations in the Grand Teton area.
Goats and sheep have extensive overlap in habitat requirements and an area that could
support sheep should also support goats. Winter habitat requirements do differ somewhat
between species. Bighorn sheep often migrate to lower elevations (Woolf et al. 1970; Keating
et al. 1985; Martin 1985) while goats tend to winter in or near their high altitude summer
range (Chad wick 1977; Rideout 1977). If the snow is too deep for goat survival in higher
elevations, winter could limit goat distribution and numbers more than sheep. If winter
conditions are the factors limiting expansion of goats into Yellowstone and Grand Teton
National Parks, the ephemeral status of goats would not be expected to change.

Based on sight records, pioneering goats are using habitat currently occupied by sheep
(Fig. 3). A third possible explanation for the lack of colonization of the Parks by goats is
competitive exclusion by sheep. There is some ambiguity in the literature as to competitive
interactions between sheep and goats. Goats and sheep co-occur over most of the range of
mountain goats without obvious effects on either species. Observations range all possible
outcomes from no interaction (Holroyd 1967) to seemingly aggressive behavior by sheep and
goats (Reed 1986 & unpubl. data). Reed (1986) found over 50% of the interactions he
recorded between sheep and goats to be neutral but 41% of the time, goats displaced sheep
from a resource (feeding site, bed area, etc). Whitfield (1983) concluded sheep, at least in
Grand Teton Park, would be the weaker competitors. It is unlikely the presence of sheep
would prevent colonization of the Parks by goats. Goats and sheep rarely interact
aggressively and when they do, goats are most often the aggressor.

Of the possible factors that may account for the limited presence of goats in the Parks,
the most likely explanation for their current distribution is a lack of sufficient time and /or
founding individuals to establish core populations.

IMPACT OF GOAT COLONIZATION

Impact on Park habitat

Location and size of impact areas\-\i the current low occurrence of goats in both Parks
is a result of competition with sheep or lack of sufficient habitat, then goat numbers in either
Park would not increase much beyond current levels. However, if goat numbers are
currently low because of insufficient time and /or numbers of pioneering animals, the number
of goats within each Park would eventually increase.

If mountain goats will ultimately colonize interior areas of both Parks, it is necessary
to try and predict the areas most likely to be colonized and the maximum number of goats
that might occur. Reported densities of goats elsewhere vary considerably among studies
(Hayden 1989). These variations can reflect true differences in population densities as well

13

as different modes of calculation. Population density can be based on the total area of a
watershed or only on the area of observed use. Densities can also be calculated based on the
size of summer or winter ranges. The calculations for this report are based on total available
area of the summer watershed. This was done because of the uncertainty of exactly which
areas goats would actually occupy in the Parks. To generate estimates of total population
and population densities for Yellowstone Park, I used data from Swenson's (1985) study of
goats in the Absaroka mountains. For Grand Teton Park, I used data from the Palisades
population (Hayden 1984;1989).

From 1981 to 1983, Swenson (1985) found a population of 90-96 animals in the
Absaroka area. His study area was approximately 275 km2. If it is assumed 95 animals
represents a stable population, the population density of his study area was 0.34 goats /km2.
No estimate of the amount of suitable goat habitat in Yellowstone Park exists. The
topography of the mountain ranges is gradual enough that nearly all mountainous areas are
usable by bighorn sheep in the summer. Summer habitat use by goats and sheep overlap
extensively (Adams et al. 1982b). Assuming the 250 km2 of sheep habitat in Yellowstone
Park (Anonymous 1987b) would also be suitable for goats, the total number of goats the Park
would support, at 0.34 goats/ km2, would be 95 animals.

The densities found in Swenson's study area compare to the lower density estimates
from other studies (Hayden 1989). Densities of goats from other areas range from a high of
15.4/ km2 found in Glacier National Park (Singer and Doherty 1985) to a low of 0.2 /km2 in
British Columbia (Herbert and Turnbull 1977). The summer range densities of various
studies reported by Hayden (1989) were averaged and had a mean of 1.9 goats/km2.
Densities in northern Yellowstone are not likely to be higher than 1.9 goats/ km2. This
density is five times higher than that reported by Swenson and should be sufficient to
accommodate any eruptive growth (Caughley 1970) in this area, even in the absence of
hunting. Consequently, this density was used to generate a high estimate of 522 goats for
the Park.

Potential goat habitat in Yellowstone is dispersed among several fragmented mountain
ranges. Some of these ranges, e.g., Mt. Washburn, may be too small to support as high a
density of goats as larger ranges. The quality of goat habitat likely varies among the ranges,
also affecting accuracy of the calculations. Consequently, the density of goats would vary
considerably among the different ranges in the Park and the total number of goats that might
inhabit the Park is difficult to predict. However, the high and low estimates should represent
a realistic range of possible numbers.

Hayden (1989) found goat densities for summer range in the overall Palisades study
area averaged 6.8 goats/ km . There are 83 km2 of existing sheep habitat in Grand Teton
Park (Anonymous 1987b). If habitat within Grand Teton Park, could support this density,
the number of goats possible in the Park would be 564. The density found by Hayden is
considerably higher than most other areas and might represent a peak in an eruptive growth
phase for that area. Because of the high densities found near GTNP, the low density estimate
from the area north of Yellowstone Park may not be realistic for Grand Teton Park. To
develop a range of possible numbers of goats, the average density of 1.9 goats /km2 was used
to calculate a low estimate of 158 goats.

In Grand Teton Park, it is difficult to determine how much potential habitat exists a
priori, without extensive field analysis. Goats can use more rugged and steeper areas than
sheep and could likely use more of the precipitous habitat in Grand Teton Park than sheep,

14

provided adequate food existed. Thus the estimates of potential goat numbers based only
on current sheep habitat could be underestimated.

Suring et al. (1988) developed a habitat capability model for mountain goats in Alaska
which is currently being verified by the authors. The main factors in the model are habitat
type, aspect, and distance from escape terrain (Fox 1983). Goats in southeast Alaska use
forested areas more than goats in Montana (Peck 1972; Fox and Smith 1988). However,
modifications could be made to this model to correspond to conditions in the intermountain
west. The model could then be used to assess the habitat suitability of potential range in the
Parks and calculate more accurate population estimates. The model would require detailed
field analysis of the potential habitat for each Park. Such detailed field work was not in the
scope of this project. However, it is recommended that such an effort be undertaken once
the model has been verified and modified appropriately.

Habitat composition of impact flreasi-Alpine and subalpine communities in Yellowstone
and Grand Teton Parks are characteristic of such communities in the intermountain west.
Structurally, the communities consist mainly of low growing grasses, forbs, and shrubs.
Subalpine communities will have varying percents of evergreen trees. Typical species found
in alpine and subalpine communities in Yellowstone and Grand Teton Parks were listed in
Martin (1985) and Whitfield (1983) respectively and are summarized in Table 3.

Whitfield (1983) measured percent cover for various vegetal components of summer
range of bighorn sheep in Grand Teton Park. He found grasses and grasslike plants with
11% cover (Table 4), forbs had 28% cover, and shrubs and trees constituted 11% cover.
Keating et al. (1985) estimated summertime percent cover for grasses, forbs and shrubs for
the Mt. Everts and Cinnabar winter ranges in and near Yellowstone Park (Table 4). Grasses
had 60% cover on Mt. Everts and 50% in the Cinnabar area. Forbs covered 18% of the
ground on Mt. Everts and 13% in the Cinnabar winter range. Shrubs constituted 21% of the
canopy on Mt. Everts and 37% in the Cinnabar area. Stewart (1975) assessed percent cover
for grasses, forbs, and shrubs on the West Rosebud area in the Beartooth Mountains north
of Yellowstone Park (Table 4). He found percent grass cover varied from 2% to 38% and
forbs ranged from 4% to 82%.

The Wolverine Peak area has been identified as the initial colonization site of goats
in Yellowstone Park. If goat numbers increase in this area, it is important to have baseline
data on percent cover of alpine vegetation for future comparisons. In the summer and fall
of 1988, permanent photoplots were established and photographed. Three general areas were
selected for sampling. Area 1 is the south side slope of Wolverine Peak. Area 2 is the west
side slope and Area 3 is a plateau area down slope from the west side location (Fig. 4).
Selection of these areas was based on observations of mountain goat use. Ten photoplots per
area were randomly selected. All sample points were on slopes without trees or shrubs.
Approximate locations of the photoplots are shown in Figure 4.

Total percent cover in summer and fall was lowest in Area 1 and highest in Area 3
(Table 4). Goats have only recently invaded the area and are still in low numbers. The
percent cover measurements taken in these three areas should provide baseline data for
future comparisons when or if goat numbers increase.

15

Tabic 3. Lkl of grass, fori), and woody species found in alpine and subalpine communities in Yellowstone and Grand Teton National Park*
(Whitfield 1963; Martin 1985).

Species

Common Name

Status

(Hitchcock & Cronquist 1973)

(Hitchcock & Cronquist 1973)

(Shaw 197*.')

Grass and grasslike plants

Agropynn caninum

Bearded whealgrass

_b

Agropyron scibneri

Spreading whealgrass

Frequent

Agropyron spicatum

Bluebunch wheatgrass

Frequent

Agrostis humilis

Alpine benlgrass

Infrequent

Agrostis scabra

rough hair-grass

Frequent

Agrostis thurberutna

Thurber bentgrass

Rare

Agrostis variabilis

Variant bentgrass

Rare

Alopercurus alpinus

Alpine foxtail

Rare

Bromus ciliatus

Columbia brome

Bromus inermis

Smooth brome

-

Calamagrostis canadensis

Bluejoint reedgrass

Frequent

Calamagrostis scopulorum

Cliff reedgrass

Rare

Carex albomgra

Black and while scaled sedge

Carex concinntodes

Northwest sedge

Carex dynoides

Kobresia-like sedge

Frequent

Carex geyeri

Elk sedge

Common

Carex paysonis

Payson sedge

Frequent

Danthonu California

California oalgrass

Rare

Deschampsia atropurpurea

Mountain hairgrass

Frequent

Deschampsia cespitosa

Tufted hairgrass

Frequent

Deschampsia eiongata

Slender hairgrass

Rare

Festuca idahoensis

Idaho fescue

Frequent

Fcstuca ovina

Sheep fescue

Frequent

Juncus drummondii

Drummond's rush

Frequent

{uncus parry i

Parry's rush

Frequent

funcus tenuis

Slender rush

Koeleria cristata

Koeleria 's junegrass

Frequent

Luzula parviflora

Small flower wood rush

Common

Luzula hitchcockii

Smooth woodrush

Common

Oryzopsis hymenoides

Indian ricegrass

Infrequent

Phleum alpinum

Alpine timothy

Frequent

Poa alptna

Alpine bluegrass

Infrequent

Poa grayana

Gray's bluegrass

Infrequent

Poa juncifolia

Alkali bluegrass

Frequent

Poa nevadensis

Nevada bluegrass

Rare

Poa rupicola

Timberiine bluegrass

Rare

Sitanwn hystrix

Bottlebrush squirreltail

Frequent

Sttpa lettermanii

Lelterman's needlegrass

Frequent

Stipa Occident alu

Western needlegrass

Rare

Thsetum spicatum

Downy oat-grass

Frequent

Forbes

Achillea millefolium

Yarrow

Infrequent

Agoseris giauca

Pale agoseris

Frequent

And rosace septentrionalis

Northern rock jasmine

Infrequent

Anemone multifida

Pacific anemone

Infrequent

Antennaria alptna

Alpine pussy-toes

Frequent

Antennaha corymbosa

Flat topped pussy-toes

Common

Aquilegia flavexcns

Yellow columbine

Infrequent

Arabia lyallii

Lyall'a rockcress

Frequent

Arena ru congesta

Ballhead sandwort

Common

Arenarta nuttallii

Nullah's sandwort

Rare

Arenaria obtusiloba

Arctic sandwort

Frequent

Arena rut rossii

Ross sandwort

.

16

Table X

Species Common Name

Status

(Hitchcock It Cronquist 1973)

(Hitchcock & Cronquist 1973)

(Shaw 1976')

Arnica cnrdifolia

Heart-leaf arnica

Common

Arnica lalifolu

Mountain amica

Frequent

Arnica longifolia

Seep-spring arnica

Arnica parryi

Nodding amica

Frequent

Arnica rydbergii

Rydberg's amica

Artemisia frigida

Fringed sagebrush

Infrequent

Artemisia michauxiana

Michaux sagebrush

Rare

Artemisia scopulorum

Alpine sagebrush

Rare

Aster alpigenus

Alpine aster

Frequent

Astragalus alpinus

Alpine milkvetch

Common

Astragalus kentrophyta

Kentrophyta

Frequent

Astragalus vexillipexus

Balsamorhiw sagittata

Arrowleaf balsamroot

Abundant

Bupleurum americanum

American thorway

Frequent

Caltha leptosepala

Elkslip

Frequent

Campanula parryi

Parry's harebell

Castilleja cusickii

Hairy indian paintbrush

Castilleja pulchdla

Showy indian paintbrush

Frequent

Cerastium bernngianum

Alpine chickweed

Frequent

Chaenactis alpina

Alpine dusty maiden

Frequent

Cirsium sea no sum

Elk thistle

Common

Claytonia lanceolate

Western springbeauly

Common

Claytonia megarhna

Alpine springbeauly

Rare

Cymopterus hendersonii

Henderson's cymopterus

Frequent

Dodecatheon conjugens

Shooting star

Frequent

Draba crassijolia

Thickleaved draba

Infrequent

Draba densifoha

Nullall's draba

Draba lonchocarpa

Lancefruit draba

Infrequent

Draba oligosperma

Few -seeded draba

Frequent

Epilobium angustiplium

Fireweed

Abundant

Epilobium glaberrimum

Smooth willow-weed

Ertgeron compositus

Culleaved daisy

Infrequent

Engeron rydbergii

Rydberg's daisy

Engeron stmplex

Alpine daisy

Ertogonum ovalifolium

Oval-leaf eriogonum

Frequent

Eriogonum umbdlatum

Sulfur buckwheat

Common

Eritrichium nanum

Pale alpine forget-me-not

Frequent

Erysimum asperum

Rough wallflower

Infrequent

Fragaria vesca

Woods strawberry

Frequent

Frogana virgmiana

Broadpelal strawberry

Frequent

Galium trifidum

Sweet scented bedslraw

Frequent

Centiana algida

Whitish gentian

-

Ceum rossii

Rom' avens

Frequent

Hedysarum sulphurescens

Yellow hedysarum

Lewisia pygmaea

Alpine lewisia

Frequent

Uoydia serotina

Alpine lily

Infrequent

Linnaea boreal is

Twin flower

Frequent

Linum perenne

Blue Flax

Frequent

bomattum cous

Cous biscuit-root

Frequent

Lupinus argenteus

Silvery lupine

Common

Lupinus sericeus

Silky lupine

Abundant

Mertensia alpina

Alpine bluebell

Mertensia ciliata

Broad -leaf bluebell

Frequent

Myosotis sylvatica

Alpine forget-me-not

Infrequent

Oenothera caespitosa

Tufted evening primrose

Infrequent

Oxyria digyno

Mountain sorrel

Frequent

Oxytropis sericea

Silky crazyweed

Frequent

Parnassia fimbriata

Fringed parnassia

Frequent

Pedicularis bracteosa

Bracled pedicularis

Frequent

17

Tabic 3. cont.

Species

Common Name

Status

(Hitchcock & Cronqu.si 1973)

(Hitchcock k Cronquist 1973)

(Shaw 1976*)

Pedicularis groenlandica

Elephantshead

Common

Penstemon fruticosus

Shrubby penstemon

-

Penstemon procerus

Small-flowered penstemon

Frequent

Phacdia hastata

Silverleaf phacelia

Frequent

Phacdw sericea

Silky phacelia

Frequent

Phlox pulmnata

Cushion phlox

Frequent

Polemomum viscosum

Sticky polemonium

Frequent

Polygonum bistortoidcs

Western bistort

Common

Polygonum viviparum

Alpine bistort

Infrequent

Potcntilla diversifolia

Diverse- leaved cinquefoil

Common

Potentilla gracilis

Soft cinquefoil

Common

Potcntilla quinquefoiia

Five-leaved cinquefoil

Potcntilla recta

Erect cinquefoil

Ranunculus eschscholtzii

Subalpine butlerweed

Widespread

Saxifraga arguta

Brook saxifrage

Saxifraga bronchialis

Yellowdot saxifrage

Common

Saxifraga flagdlaris

Sloloniferous saxifrage

Rare

Saxifraga oppositifolia

Purple saxifrage

Frequent

Saxifraga oregana

Bog saxifrage

-

Saxifraga rhomboidea

Diamond-leaf saxifrage

Frequent

Sedum lanceolatum

Lance-leaf stonecrop

Common

Sedum roseum

Rose root

Frequent

Sedum stenopetalum

Wormleaf sedum

Infrequent

Senecto canus

Wooly groundsel

Infrequent

Senecto crassulus

Thick-leaved groundsel

Frequent

Seneco fremontii

Dwarf mountain butlerweed

-

Senecto fuscatus

Twice hairy butlerweed

-

Seneco serra

Tall butlerweed

Frequent

Senecto triangularis

Arrow-leaf groundsel

Common

Senecto werneruiefolius

Rock butlerweed

Sibbaldia procumbens

Creeping sibbaldia

Frequent

Silene acauhs

Moss champion

Frequent

Smelowskia calycina

Alpine smelowskia

Frequent

Solidago multiradiata

Northern goldenrod

Frequent

Stdlaria americana

American slarwort

Taraxacum lyratum

Alpine dandelion

Thalictrum occidentale

Western meadowrue

Frequent

Townsendia parryi

Parry lownsendia

Trifolium dasyphyllum

Whiproot clover

Common

Trifolium haydenii

Hayden's clover

Common

Trifolium nanum

Dwarf clover

Common

Trifolium parryi

Parry's clover

Veronica wormskjoldii

American alpine speedwell

Frequent

Viola adunca

Early blue violel

Frequent

Zygadenus degans

Alpine death camas

Infrequent

ShrubcArees

Abies lasiocarpa

Subalpine fir

Abundant

Alnus incana

Thinleaf alder '

Frequent

Ainus sinuata

Sitka alder

Arctostaphyhs uva-ursi

Kinnikinnick

Frequent

Artemisia arbuacula

Dwarf sage

Frequent

Artemisia tridentata

Big sage

Abundant

Berberts repens

Creeping Oregon grape

Frequent

Betula occidentalis

Water birch

Rare

Ceanolhus vdutinus

Snowbrush ceanolhus

Frequent

Cornus stolonifera

Red dogwood

Frequent

Dryas octopetala

White dryas

Infrequent

Juniperus communis

Common juniper

Frequent

18

Table 3. cont.

Species

Common Name

Status

(Hitchcock it Cronquist 1973)

(Hitchcock it Cronquist 1973)

(Shaw 1976J)

Phyllodoce anpetriformis

Pink mountain heath

Frequent

Phyllodocc glanduliflora

Yellow mountain heath

Infrequent

Phyxxarpus malvaceus

Ninebark

Pica engcimannii

Engelman's spruce

Common

Pinus albicoulis

Whitebark pine

Common

Pinus contorta

Lodgepole pine

Abundant

Populus tremuloides

Quaking aspen

Abundant

Potent ilia jruticosa

Shrubby cinquefoil

Common

Psevdotsuga menziesii

Douglas fir

Common

Rioes spp.

Gooseberry

Frequent

Rosa acicularis

Prickly rose

Frequent

Salix spp.

Willow

Common

Symphoncarpos spp.

Snowberry

Frequent

Vaccmium globularc

Blue huckleberry

Frequent

Vuccinium scopanum

Grouse whortleberry

Abundant

Vaccimum spp.

Blueberry

Frequent

'Status relative to Teton County, Wyoming (Grand Teton Park) and may be
different for Park County (Yellowstone Park).
'TMol listed in Shaw (1976).

Table 4. Percent cover of various areas in Yellowstone and Grand Teton Parks.

Mosses Grasses Forbs Shrubs/ Trees

Grand Teton Park (Whitfield 1983) 14%

Yellowstone Park (Keating el al

1985)

Ml. K verts

60%

18%

21%

Cinnabar area

50%

13%

37%

West Rosebud Area (Stewart 1975)
Wolverine Peak (This study)

19%

35%

12%

Area 1 Summer
Fall

39.2*14.4
23.37l73

Area 2 Summer
Fall

71.1+173

50.3727.2

Area 3 Summer
Fall

74.3+23.6
755725.4

""Grass and forb species only.

19

Figure 4. Approximate location of the three sites on Wolverine mountain where permanent photo-points were established.
Each photo-point is marked with a steel rod and a landmark of rocks.

C^^v

Yellowstone
National
Park

KilonuU T

r 1— i

0 0 5 10

20

Food preferences of mountain goate:-Researchers have studied food habits of mountain
goats in different areas of their geographic range. In one of the earlier studies, Casebeer
(1948) found goats in western Montana relying primarily on grouse whortleberry (Vaccinium
scoparium) and the sedge Carex geyeri in the summer. During the winter, goats primarily ate
junegrass (Koeleria cristata), wheatgrass (Agropyron spiaitum), and willows (Salix sp.). Hjeljord
(1973) reported summer food of goats in Alaska consisted of various forbs, depending on the
habitat type they used. In winter, goats primarily fed on rough fescue grass (Festuca sp.) and
coiled sedge (Carex sp.). Fox and Smith (1988), however, found Alaskan goats they studied
relying more on mountain hemlock {Tsuga mertensiana), mosses (Hylocomium sp.), and lichen
(Lobaria sp.) in the winter.

Table 5. Summary of general food habits of goals from various studies. Estimates are expressed as percent of total use and
are based on either fecal or rumen analyses.

Summer

Winter

Grai

76% Montana
97% Colorado
22% Montana
40% Montana
60% Colorado
84% Colorado
11% Montana
47% Montana
44% Washington
53%

(Saunders 1955)
(Hibbs 1967)
(Peck 1972)
(Pallisler 1974)
(Johnson et al. 1978)
(Thompson 1981)
(Thompson 1981)
(Stewart 1975)
(Johnson 1983)

59% Montana

88% Colorado

90% Montana

45% Colorado

47% Montana

31% Washinglon

(Saunders 1955)

(Hibbs 1967)

(Peck 1972)

(Adams and Bailey 1983)

(Thompson 1981)

(Johnson 1983)

Forbes

Mean

14% Montana
3% Colorado
78% Montana
60% Montana
29% Colorado
15% Colorado
9% Montana
53% Montana
20% Washington
31%

(Saunders 1955)
(Hibbs 1967)
(Peck 1972)
(Pallisler 1974)
Gohnson et al. 1978)
(Thompson 1981)
(Thompson 1981)
(Stewart 1975)
(Johnson 1983)

10% Montana

0% Colorado

6% Montana

2% Montana

24% Colorado

3% Washinglon

(Saunders 1955)
(Hibbs 1967)
(Peck 1972)
(Thompson 1981)
(Adams and Bailey 1983)
(Johnson 1983)

Browse

2% Montana

0% Colorado

0% Montana

0% Montana

7% Colorado

1% Colorado

79% Montana

0% Montana

35% Washinglon

14%

(Saunders 1955)
(Hibbs 1967)
(Peck 1972)
(Pallisler 1974)
(Johnson et al. 1978)
(Thompson 1981)
(Thompson 1981)
(Stewart 1975)
(Johnson 1983)

30% Montana

12% Colorado

1% Montana

51% Montana

30% Colorado

65% Washington

(Saunders 1955)
(Hibbs 1967)
(Peck 1972)
(Thompson 1981)
(Adams and Bailey 1983)
(Johnson 1983)

21

Several researchers quantified goat diets for summer and winter. Their data are based
on percent use or occurrence in stomach or scats and are not adjusted for forage availability
(Rominger and Bailey 1982) relative to percent use. Table 5 summarizes their data. The data
concur with general findings of a heavy reliance on grasses (53%) and forbs (31%) in the
summer and a shift primarily to grasses (60%) in the winter.

Some researchers presented detailed analyses of food habits of goats relative to forage
species used (Table 6). Based on the results of these studies, the main summer diet of
mountain goats consists of sedges {Carex sp.), wheatgrass (Agropyron sp.), kobresia (Kobresia
sp.), bluegrass (Poa sp.), fescue (Festuca sp.), sandwort (Arenaria sp.), bluebells (Mertensia sp.),
Jacob's ladder (Polemonium sp.), groundsel (Senecio sp.), and clover (Trifolium sp.). Winter
diets consists mainly of sedges (Carex sp.), wheatgrass, fescue, bluegrass, muhly (Muhlenbergia
sp.), hairgrass (Deschampsia sp.), and spruce (Picea sp.). The data in Table 6 include results
of work in Colorado and Washington. Food habits of animals reflect preferences and
availability (Rominger and Bailey 1982). The availability of food species in Colorado and
Washington can differ from that found in Yellowstone and Grand Teton Parks and may not
be an accurate estimate of food habits of goats in these areas. Alpine and subalpine
communities in Montana should more closely parallel conditions in the Parks and provide
more realistic estimate of food preferences of goats in the Parks. If the data from the
Montana studies are considered separately, the main foods in summer diets of mountain
goats are: sedges, bluegrass, sandwort, bluebells, Jacob's ladder, and clover. Winter diets
consists of sedges and unidentified grasses.

Mountain goats can possibly affect vegetation in the Parks through direct consumption
and /or destruction by wallowing (Pfitsch 1981; Pike 1981). Based on the data in Table 6,
goats would rely primarily on three grass-grasslike genera [Agropyron, Carex, Poa, and 7
genera of forbs (Arenaria, Arnica, Erigeron, Mertensia, Polemonium, Polygonum, and Trifolium.
Most of the alpine species in these genera are frequent to common in their occurrence in
Yellowstone and Grand Teton Parks (Table 3). Unless goat densities attain the high estimates
projected, no adverse affect from grazing by goats on these genera of plants is expected.

In Olympic Park, goats were found to affect rare and /or endemic species even at low
levels of grazing pressure (Pike 1981). There are no known endemic alpine plant species nor
species listed as endangered or threatened in Yellowstone Park. There is one species, Shultz's
milkvetch (Astragalus shultziorum) in Grand Teton Park listed as a Category 2 candidate for
Federal listing (R.P. Wood, Personal Communication, GTNP). However, little is known of
its distribution and its taxonomic status is in debate. There are also 13 species listed in Table
3 classified as rare. Little is also known of the distribution of most of these species. Until
more is learned of the distribution of these species relative to potential goat colonization sites,
it is not possible to assess the impact goats might have on them. If these species occur in
areas of goat colonization and goats become numerous or selectively feed on them, goats
could negatively impact these species. »

Impact of goats on surrounding National Fores/s:~Goats in Olympic Park had a major
impact on the physical and floral environment through their extensive wallowing (dust
bathing) behavior (Hutchins and Stevens 1981; Pike 1981, Pfitsch 1981; Reid 1983). Goats
significantly reduced percent plant cover and created wallows which eroded extensively. On
10 September 1988, a survey was made of goat range on Mt. Baldy in the Swan Valley area
of Idaho. Goat densities are considered extremely high (10.8/knr) (Hayden 1989) on Mt.

22

Table 6. Summary of specific plants used by goals

Adams it

Jon niton

Peck

Ilibbs

Bailey

Pallisler

etal.

Thompson

Stewart

Johnson

1972

1967

1983

1974

1978

1981

1«75

1983

Specie.

Summer Winter

Summer

Winter

Winter

Summer

Summer

Summer Winter

Summer

Summer Winter

Grasses

Unidentified

2% 82%

-

7%

1%

Agropyron sp.

<1%

29%

4%

2%

-

6%

-

8%

18%

13%

Agrostts scabra

-

1%

Avena sp.

-

<1%

Bromus sp.

-

Calamagrostis sp.

<1%

4%

2%

Carex sp.

19% 7%

8%

11%

29%

4%

33%

3%

6%

1%

Deschampsu sp.

-

1%

<1%

3%

<1%

1%

-

Festuca sp.

-

3%

26%

12%

<1%

18%

7%

43%

4%

7%

Hdictotrichon sp.

-

2%

J uncus tenuis

Kobresia sp.

-

36%

6%

-

-

Kocleru cristate

<1%

1%

-

-

luzula sp.

<1%

1%

<1%

Muhlenbergia montana

27%

1%

Poo sp.

-

16%

12%

1%

36%

4%

2%

39%

5%

7%

Sitanion sp.

-

<1%

S/;pa robust a

-

2%

2%

-

Tnsetum spicatum

-

2%

<1%

-

Porta

Unidentified

Achillea millefolium
Agoseris sp.
Antennana alpina
Aqutlegia flavescens
Arenarw sp.
Arnica sp.
Artemisia sp.
Aster sp.
Astragalus sp.
Caltha leptoscpala
Caslilleja pulchdla
Cerastium sp.
Dexuratnia sp.
Erigeron sp.
Eriognum sp.
Gentiana sp.
Geum rossii

Haplopappus macronema
Heracleum sp.
Heuchera sp.
Lcsquerdla sp.
Lupinus sericeus
Mertensia sp.
Penstemon sp.
Polemonium viscosum
Polygonum bistortoides
Potentilla sp.
Ranunculus sp.
Saxifraga bronchialis
Sedum stenopetalum
Senecio sp.
Silent sp.
Trifolium sp.
Verba scum sp.

cl%

22%

1%

24%

<1%

2%

29%

1%

<1%

<1%
<1%
<1%
<1%

<1%

<1%

<1%
<1%

<1%
<1%

<1%
<1%
<1%

<1%
<1%

3%

<1%

1%

0%

1%

-

cl%

= 1%

3%

2%

2%

2%

<1%

= 1%

1%
<1%

4%

3%

1%

2%

20%

14%

6%

% 3%

1%

:1%

<1%
10%

3% 1%

<1%

1% <1%

2% 10% 1%

3%

1%

2%

1%

1%

23

Tabic 6. conl

Adams &

Johnson

Peck

Hibbs

Bailey

Pallister

etal.

Thompson

Stewart

Johnson

1972

1967

1983

1974

1978

1981

1975

1983

Specie*

Summer Winter

Summer Winter

Winter

Summer

Summer

Summer W

inter

Summer

Summer Winter

Woody specie*

Unidentified

11% 12%

Abies sp.

2%

•

-

Acer giabrum

-

-

%

-

Alnus sp.

<1%

-

-

Amdanchier sp.

-

<1%

4%

Artemisia sp.

-

-

7% 3%

Berbens sp.

-

-

8%

2%

Ceanothui sp.

-

-

1% 6%

Cercocarpus montanus

-

%

3%

Unidentified conifers

-

6% 28%

Dryas octopetala

-

<1%

Haplopappus sp.

<1%

-

lumper us sp.

<1%

-

-

Phyllodoce glanduliflon

<1%

-

Picea sp.

-

28%

-

Pinus sp.

<1%

-

<1%

-

<1%

<1%

Pseudotsuga sp.

<1%

-

13%

Ribes sp.

-

1%

<1%

2%

1% 5%

Rosa sp

-

5%

Rubus sp.

-

1%

<1%

Salix sp.

0 <1%

»%

1%

30%

2%

Sambucu* sp.

-

»%

1%

Shepherdia sp

-

42%

28%

9% 5%

Symphoncarpos sp.

-

<1%

VacriniMm sp.

0 <1%

Baldly but only limited damage from wallowing by goats was found. A few small wallow
depressions were found along ridge edges. No major erosion from these depressions was
seen. Five randomly chosen photoplots were sampled on a slope considered characteristic
of goat use in that area. Combined percent cover of grasses and forbs averaged 28.7+11.7 %
for these plots and was comparable to similar habitat in Yellowstone Park (Table 4).

On 25-26 July 1988, 1 visited Glacier National Park, another area characterized by high
goat densities (2.8 goats /km2; Chad wick 1974). Near Logan Pass, an area of high goat
concentrations, no evidence of extensive habitat destruction by goats was found. These
findings are in contrast to Olympic National Park (14 goats /km2; Stevens 1983) where
extensive wallowing by goats has had a major impact on the physical and floral environment.
It is unclear why goats should have an increased impact in Olympic Park but not other areas.
Goats wallow to cool off and /or protect themselves from insect pests (Hutchins and Stevens
1981; Chadwick 1983). The summer climate in Olympic Park is milder than interior areas and
could account for the increased wallowing by goats. Olympic Park also receives substantially
more rainfall than Swan Valley and Glacier Park and could exacerbate the effect of
wallowing.

24

Based on the observations made in Glacier National Park and the Swan Valley area,
environmental modification by wallowing goats in Yellowstone and Grand Teton Parks is
predicted to be minimal at low density estimates. At high goat densities some damage may
occur locally if goats concentrate their activity in selected areas. This damage, however, is
not expected to be as severe as experienced in Olympic National Park.

Impact of mountain goats on bighorn sheep

Goat-sheep interadions:-Oi all the fauna! species in the Parks, increasing mountain goat
populations would most likely affect bighorn sheep. Goats and sheep have similar niches
along several resource axes (Adams et al. 1982b) and co-occur over much of their respective
ranges. Mountain goats and bighorn sheep could compete for these resources through either
interference or resource competition.

With regards to interference competition, few qualified recorded instances of goats and
sheep interaction were found in the literature. Holroyd (1967) observed sheep and goats
together but never saw any "intolerance" between the species. Stewart (1975) reported seeing
sheep and goats in close proximity on six occasions. Five of the times, sheep and goats fed
within 300 m of each other with no apparent concern. The sixth instance involved a pregnant
ewe, believed to be looking for a lambing site, moving away from the area when a goat
approached. During this study, I saw goats and sheep in the Wolverine Peak area feeding
within 100 m of each other without apparent concern. In Glacier National Park, I also viewed
a band of approximately 25 goats feeding within 200 m of a band of 15 sheep, again without
apparent concern from either. Reed (1986 & unpubl. data) studied interactions between
sheep and goats in Colorado. Out of 69 instances of direct interactions, 54% were neutral.
Goats prevented sheep from using a particular resource (bedding site, feeding area, etc) 41%
of the times but did not cause the sheep to leave the area. Sheep caused movement of goats
only 5% of the instances. The fewest interactions were in the winter and all of them were
neutral.

Based on the limited data available, goats seem to be mildly agonistic toward sheep.
Individual goats will displace individual sheep from particular resources but will rarely
displace or chase them from the immediate area. Such agonistic interactions are minimal
during the winter months when they might have the greatest affect on survival of
individuals.

To assess resource competition, between mountain goats and bighorn sheep, it is
necessary to identify the resources goats and sheep would most likely compete for. For goats
and sheep the two most critical resources would be food and habitat. Thus food and habitat
requirements of sheep were determined and compared to the requirements of goats.

Food habits of Bighorn S/ieep:~Studies on food habits of sheep, including sheep in both
Yellowstone and Grand Teton Parks, indicate bighorn sheep generally rely on a variety of
grass and forbs (Davis 1938; Honess and Frost 1942; Spencer 1943; Couey 1950; Smith 1954;
McCann 1956; Berwick 1968; Cooperrider 1969). There have been several studies quantifying
food habits of bighorn sheep. Table 7 summarizes the results of these studies relative to
grasses, forbs, and browse. Based on these studies, diets of sheep and goats are quite similar

25

Tabic 7. Summary of general food habits of bighorn sheep from various studies. Figures are expressed as percent of total
are based on either fecal or rumen analyses.

Winter

60% Yellowstone

75% Colorado

12% Montana

95% Montana

44% Montana

65% Colorado

46% New Mexico

25% Grand Teton

74% Montana

30% Washington

51% Wyoming

88% Colorado

(Mills 1937)
(Moser 1962)
(Pallister 1974)
(Friaina 1974)
(Stewart 1975)
(Todd 1975)
(Johnson & Smith 1980)
(Whitfield 1983)
(Martin 1985)
(Esles 1979)
(Honess & Frost 1942)
(Harrington 1978)

Mean

98% Yellowstone

61% Yellowstone

98% Montana

92% Montana

40% Montana

23% Colorado

83% New Mexico

30% Grand Teton

39% Montana

56% Yellowstone

87% Montana

62% Washington

65% Montana

54% British Columbia

72% Montana
64%

(Mills 1937)

(Oldemeyerel al. 1971)
(Pallister 1974)
(Frisina 1974)
(Stewart 1975)
(Todd 1975)
(Johnson & Smith 1980)
(Whitfield 1983)
(Martin 1985)
(Keating et al. 1985)
(Schallenberger 1966)
(Estes 1979)
(Kasworm et al. 1984)
(Blood 1967)
(Conslan 1972)

Fort*

35% Yellowstone

6% Colorado

55% Montana

4% Montana

6% Colorado

47% Montana

50% New Mexico

12% Grand Teton

16% Montana

8% Washington

30% Wyoming

12% Colorado

(Mills 1937)
(Moser 1962)
(Pallister 1974)
(Frisina 1974)
(Todd 1975)
(Stewart 1975)
(Johnson & Smith 1980)
(Whitfield 1983)
(Martin 1985)
(Estes 1979)
(Honess & Frost 1942)
(Harrington 1978)

Mean 23%

0% Yellowstone

17% Yellowstone

2% Montana

6% Montana

11% Colorado

40% Montana

10% New Mexico

32% Grand Teton

50% Montana

7% Yellowstone

9% Montana

3% Washington

12% Montana

5% British Columbia

17% Montana

15%

(Mills 1937)

(Oldemeyer et al. 1971)
(Pallister 1974)
(Frisina 1974)
(Todd 1975)
(Stewart 1975)
(Johnson St Smith 1980)
(Whitfield 1983)
(Martin 1985)
(Keating el al. 1985)
(Schallenberger 1966)
(Esles 1979)
(Kasworm el a I. 1984)
(Blood 1967)
(Constan 1972)

Browse

5% Yellowstone

19% Colorado

32% Montana

1% Montana

29% Colorado

8% Montana

4% New Mexico

63% Grand Teton

10% Montana

62% Washington

19% Wyoming

0% Colorado

21%

(Mills 1937)
(Moser 1962)
(Pallister 1962)
(Frisina 1974)
(Todd 1975)
(Stewart 1975)
(Johnson & Smith 1980)
(Whitfield 1983)
(Martin 1985)
(Esles 1979)
(Honess St Frost 1942)
(Harrington 1978)

0% Yellowstone

22% Yellowstone

0% Montana

1% Montana

67% Colorado

20% Montana

7% New Mexico

39% Grand Teton

10% Montana

38% Yellowstone

2% Montana

35% Washington

23% Montana

40% British Columbia

8% Montana
21%

(Mills 1937)

(Oldemeyerel al. 1971)
(Pallister 1962)
(Frisina 1974)
(Todd 1975)
(Stewart 1975)
(Johnson St Smith 1980)
(Whitfield 1983)
(Martin 1985)
(Keating el al. 1985)
(Schallenberger 1966)
(Esles 1979)
(Kasworm el al. 1984)
(Blood 1967)
(Constan 1972)

26

Table 8. Summary of specific food habits of bighorn sheep.

Oldemeyer

Whitfield

1983

1974

1974

Stewart Mills

1975

1937

1985

Johnson Keating Consljn tUsworm

& Smith et at. ct at. el al.

1980 1985 1971 197: WM

Sum Win Sum Win Sum Win Sum Win Sum Sum Win Sum Win Wi

Win Win

Win

Crass and grass

-like s

pecies

Unidentified

.

1%

1%

19%

11%

Agropyntn

<1%

<1%

39%

37%

5%

2%

-

<1%

22%

25%

40%

21%

AgroU is

<1%

<1%

-

<1%

-

Alopecurus

-

1%

-

-

-

Bromus

5*

5%

3%

1%

<1%

-

5%

1%

3%

Calamagrostis

-

<1%

1%

Carex

5%

17%

<1%

-

4%

22%

13%

20%

-

52%

15%

27% 63%

3%

3%

1%

4%

Danthonia

-

-

-

-

-

3% 6%

-

Deschampsia

1%

<1%

-

-

<1%

-

3%

-

6%

4%

4% 5%

-

Equtsetum

<1%

Festuca

4%

3%

35%

26%

1%

11%

11%

18%

7% 10%

5%

9%

23%

18%

Hesperochloa

-

7%

/uncus

<1%

<1%

2%

Koeleria

1%

1%

4%

6%

1%

9%

7%

7%

Luzula

<1%

<1%

<1%

-

Oruuopis

<1%

-

6%

-

1%

1%

<1%

-

-

Phleum

<1%

<1%

57%

<1%

Poo

7%

2%

12%

7%

18%

60%

2%

1%

<1%

5%

4%

<1%

Sitanwn

-

14%

<1%

St ma

<1%

<1%

6%

10%

1%

3%

Forbs

Unidentified

2%

3%

<1%

-

-

<1%

5%

Achillea

<1%

<1%

-

-

<1%

Agoserts

6%

Antennarm

1%

<1%

-

Apocunum

3%

<1%

Aqutlegw

-

5%

<1%

-

Aplopappus

-

-

<1%

Arnica

6%

3%

Artemisia

<1%

<1%

2%

2%

1%

25%

10%

Astragalus

2%

4%

<1%

4%

3%

2%

3%

<1%

2%

<1%

Balsamorhiza

3%

<1%

2%

Caltha

<1%

Castilleja

2%

-

Cirsium

-

-

<1%

1%

1%

<1%

Composilae

<1%

-

<1%

<1%

1%

<1%

Cruciferae

-

<1%

<1%

Delphinium

<1%

-

-

Descurainia

<1%

2%

<1%

Draba

<1%

6%

<1%

Epilobtum

-

-

4%

Erigeron

-

-

<1%

5%

<1%

1%

Ertgonum

<1%

<1%

-

<1%

<1%

Eurolia

<1%

-

Fabaceae

-

<1%

<1%

Fem

1%

.

Geum

.

31%

Lesquerdla

2%

2%

-

1%

Lichen

<1%

-

-

-

27

Table ft. rant.

Whitfield

Frisina

Pallisler

Stewart Mills Martin

1983 1974 1974 1975

Sum Win Sum Win Sum Win Sum Wi

1937 1985

Sum Sum Win

Oldemeyer

Johnson Keating Constan Kasworm

St Smith et al. el al. et al.

1980 1985 1971 1972 1984

Sum Win Win Win Win Win

Uoydia

Luptnus

1%

2%

Meriensia

-

Oxytwpii

Pedtulam

-

-

Phacdia

•

-

Phlox

<1%

8%

Plantago

Polemonium

-

Polygonum

-

PotentMa

2%

1%

1%

Saxifraga

<1%

3%

Seneca

Sibbaldia

<1%

Silent

Sol tda go

1%

<1%

Sphaeralcea

<1%

St HI aria

<1%

<1%

Trifaltum

<1%

Zygadenus

2%

<1%

2%

<1%
1%

2%

<1%
% <1%

2%

4%

2%

25%

5% 16%

1%

1% 23%

3% 4%
<1%

2% 6% 1%

12% 1%

Abies

2%

Ainu*

1%

Ameianchier

<1%

<1%

Artemisia

<1%

<1%

<1% -

20%

Berberts

1%

<1%

<1%

<1%

Ceanothus

4% -

Chrysotnamnus
F.urotia

; ;

lumperus

Physocarpus

Picea

<1%
<1%

<1%
3%

2% -

<i%

Pinus

<1%

7%

<1%

<1%

1%

Populus

<1%

<1%

Prunus

2% - <

1%

<i%

Pseudotsuga
Ribet

7%

13%

19% -

Rosa

<1%

<1%

%

1%

RubuB

<1%

Salix

28%

12%

<1% -

%

5%

Shepherdia

SymphoricarpoB

Vacctnium

14%
12%

3%
<1%

<1% -

%
1%

: ;

2%

4%

16% 3%

4% 8%

14% 10%

15%

2%

<1%
<1%
<1%
1%

28

throughout the year. As with goats, several of the researchers presented a breakdown of the
specific plants used by bighorns. The summary of specific plant genera used by sheep is in
Table 8.

Of the plant species in Tables 6 & 8, only a few were used by goats and /or sheep >1%.
These preferred genera, and estimates of their use by goats and sheep are presented in Table
9. Data in Table 9 were used to calculate indices of resource overlap (Lawlor 1970) (Fig. 5).
The indices indicate overlap in food habits of goats and sheep but, based on Tables 6 and 8,
they both have diets that vary spatially and temporally. The variability in diets is mainly
attributable to both species selecting foods based on differing availability among areas. To
best determine overlap in diets, it is necessary to compare food preferences of sympatric
populations. Data from several such studies are available. Dailey et al. (1984) conducted
parallel feeding trials on goats and sheep in Colorado (Table 10). These data were also used
to calculate indices of resource overlap (Fig. 5). Diets of sheep and goats overlapped
substantially in the summer (O = 0.97) but dropped to 0.64 in the winter. This decrease in
overlap in the winter resulted from goats eating more forbs and sheep consuming more
grasses.

Pallister (1974) and Stewart (1975), working with sheep in the Beartooth mountains
north of Yellowstone Park, also recorded food habits of mountain goats observed in their
study area. Pallister (1974) found summer diets of mountain goats consisted of 40% grasses
and 60% forbs. During the same time, sheep consumed 12% grass, 55% forbs, and 32%
shrubs. Although both species relied on forbs to a similar level, comparisons of specific forb
species eaten (Table 11) indicate little overlap except for clover (Trifolium parryi). Stewart
(1975) found a similar reliance on grasses by sheep (44%) and goats (47%) but goats relied
most on Poa sp. while sheep were more evenly divided among three species (Table 11).

Table 9. Comparison of specific preferred plant genera for goals and sheep. The percenls are averages of the values reported in Tables
6 and 8.

Percent use

Species

Summer

Winter

Sheep

Coals

Sheep

Goals

Agropyron sp.

6%

9%

15%

4%

Artemisia sp.

<1%

1%

10%

3%

Carex sp.

15%

10%

15%

8%

Dexhampsia sp.

2%

<1%

<1%

<1%

Festuca sp.

8%

5%

12%

18%

Koeleria sp.

<1%

5%

3%

1%

Mertensu sp

2%

6%

0%

<1%

Poa sp.

15%

14%

1%

4%

Potentilla sp.

4%

1%

<1%

<1%

Salix sp.

5%

4%

1%

1%

Stipa sp.

<1%

<1%

2%

<1%

Trifolium sp.

5%

2%

0%

<1%

29

Table 10. Summary of the findings of Dailey el al. (1984) on feeding trials for bighorn sheep and mountain goals in Colorado.

Grass Forks Browse

Summer

Goals

11%

88%

0%

Sheep

30%

70%

0%

Winter

Goals

27%

59%

14%

Sheep

75%

22%

3%

Figure 5. Resource overlap indices (O) (Lawlor 1970) for food habits of goats and sheep. Overlap indices are for pooled data
from separate studies (Table 9) and data from comparative studies of Dailey et al (1984) (Table 10) and Paliister (1974) and
Stewart (1975) (Table 11).

° 1.0

x

TJ
C

a

CO

u

>

O

0.0

[^General Diet
Summer Diets

Specific Diet
Winter Diets

Separate

Separate

Sympatric

Sympatric

Overall forb use by sheep and goats were also similar, 47% for sheep, 53% for goats but
specific use of forbs differed; most of diet of goats consisting of two species (Table 11). When
the data in Table 11 were used to calculate indices of overlap (Fig. 5), these indices averaged
0.44.

30

Pallister and Stewart had data on food habits of sheep during winter (Table 11) but did
not collect data on goat diets during that time. Thus, no comparison of winter food habits
between sheep and goats was possible.

If food use is averaged over several areas or only broad categories, food habits of sheep
and goats overlap extensively and competition for food seems likely. However, when in
sympatry, calculated amounts of overlap between summer diets of goats and sheep were

Tabic 11. Summary of findings of Pallister (1974) and Stewart (1975) on summer sheep and goal food habits. Only the major food items
used are listed.

Pallister
Bighorn Sheep Mountain Goals

Stewart
Bighorn Sheep Mountain Goats

Agropyron sp.
Carcx albomgra
Carex sp.
Deschampsta sp.
Kodena caespiiosa
Poa sp.

4%
<1%

13%
2%
2%
18%

Agoteris giouca
Aquilegw flaveacens
Apocynum androsaemiplium
Arnica lot if alia
Astragalus verxilliflexus
Caltha leptosepala
Castillqa cuskkii
Eptlobium angusttfolium
Engtron sp.
Fabaceae
Uoydia terotina
Mrrtcnsia alpxna
Mcrtensu ciliata
Polemomum viscosum
Polygonum bisiortoides
Potcntilla ovtna
Silenc acaulis
Triplium parryi

5%
5%

4%

14%

1%
17%

3%

20%

14%
b%

2%

10%

19%

31%

Shrub*

Ceanothus velutinus
Prunus virginwna
Ribes aureum
Ribes montigenum
Rubut idaeus
Safix arctica
Vaccintum sp.

4%

2%
4%
15%
2%
4%

31

reduced when specific forage species were identified. Overlap was also low during the
winter for general food categories, a time when competition could be most intense. Some of
the differences in food habits stem from different habitats selected. Differences in habitat
selection between sheep and goats found by Pallister (1974) and Stewart (1975) are addressed
in the next section.

General habitat preferences of sheep and goats:-The second general resource for which sheep
and goats could compete is habitat. Sheep and goats are both adapted to subalpine and
alpine communities. However, they are considered to have some unique requirements
(Adams et al. 1982b). Predator evasion is thought to dominate habitat selection by sheep
(Shannon et al. 1975; Adams et al. 1982b). Thus sheep prefer to forage in large groups on
abundant, open, continuous areas of forage near steep, rugged "escape" terrain. Goats
primarily live in escape terrain (Adams et al. 1982b) and predator evasion is less important.
Food resources are usually dispersed in such terrain and goats are normally found in smaller
groups than sheep. Based on this assessment, Adams et al. (1982b) concluded there was little
overlap in a variety of vegetal and structural habitat characteristics of sheep and goats.
Sheep were more adapted to using a wider range of habitat types. Goats are more limited
to tracts of rugged terrain. There is, however, some overlap in their habitat selection and
under conditions that limit selection by sheep [land development, livestock, etc. (Adams et
al. 1982b)], these areas of overlap could result in direct competition between the two species.

Several investigators have studied the details of habitat selection of sheep and goats.
Results of these studies should provide insight into the amount of overlap that may exist
between the species.

Habitat use by sheepi-Oldemeyer et al. (1971) divided the habitat in Yellowstone National
Park into three general vegetation types: forest, grass and shrub. In the winter, they found
sheep used the forest type 13%, the grass type 78%, and the shrub type 9%. When they
divided the area based on terrain, they found sheep used "steep" areas 39%, rocky outcrops
14%, ridgetops 36%, hilly areas 8%, and level areas 4% of the time. Of the numerous
structural/ vegetational formations defined by Martin (1985) in Montana, sheep spent most
of their summer time in the "alpine turf' formation (approximately 50%) and the "sparsely
vegetated dirt scree" formation (approximately 28%). In the spring, Frisina (1974) found
sheep 36% of the time in the "rocky reef" and 59% of the time in the "bunchgrass" types he
defined. In the fall, sheep use of the rocky reef type increased to 64% and decreased to 34%
in the bunchgrass type. Tilton and Willard (1982) divided their study area in Montana into
rockland, shrub /grass, open forest, and closed forest habitat types. They found sheep
spending 14% of their time in the rockland type, 46% in the shrub /grass, 40% in the open
forest, and 1% in the closed forest types.

Habitat use by goats:~Peck (1972) divided goat habitat into 4 types: timber, sliderock,
ledge, and ridge. In summer, he found goats spending 4% of their time in timber, 36% in
sliderock, 54% in ledge, and 6% in ridge areas. In winter, goats were seen 16% of the time
in timber, 70% in ledge areas, and 14% of the time on ridges. M.J. Thompson (1981) found
goats in Montana spending 90% of their time in the summer and 68% of their time in early
winter on glacial cirques. In the winter in the Bitterroot Mountains, Smith (1976) found goats
62% of the time in the "bunchgrass" association he defined. Goats in Colorado spent 85% of

32

their time in the substrate type described as "intermittent boulder" by R.W. Thompson (1981).
Adams and Bailey (1980) classified the habitat into alpine and subalpine areas. Within the
alpine community, they identified tundra and rock subcomponents. During winter, goats
spent 58% of their time in the tundra and 42% of the time in rock areas. The subalpine
community was subdivided into rock, shrubs, and trees. Goats were seen 35% of the time
in rock areas, 10% in shrub, and 55% in tree areas. Von Elsner-Schack (1986) studied goats
in Alberta and divided the study area into rock, gravel, and grass substrate types. In spring-
summer, goats used the rock substrate 24%, the gravel substrate 27%, and the grass areas
50% of the time.

Table 12. Summary of habitat use of sympalric sheep and goals in the Absaroka Mountains of Montana. The habitat classifications
were derived by the authors and detailed descriptions of each can be found in the original literature.

Pallister (1974)

Streambank Spruce/fir Rock Slreambank Alpine Rock/snow Bunchgrass Fir/shrub Meadow Rock/torest
hardwood outcrop forb tundra forb

Summer

Goats 3% - 94% 3%

Sheep 13% 13% 13% 14% 2% 10% 35%

Goats 18% 82%

Sheep - 34% 58% 5%

Stewart (1975)

Carex/Podi Carex/Podi Abla/Vax Abla/Vasc Abla/Vagl Pial/Acmi Pipo/Fcid

Rock Rock Rock Artr

Summer

Goats 81% 12% 6%

She*p 14% 14% 5% 4% 58% 3%

Goats 52% 48%

Sheep 55% 7%

Carex/Podi: Carex sp. and Polentilla dwersifolu

Alba I Vase: Abies lasiocarpa and Vaccimum scopanum

Alba /Vagi: Abies lasiocarpa and Vaccimum globulare

Pial/Acmi: Pinus albicaults and Achillea millefolium

Pipo I Feid / Arir. Pinus ponderosa, Festuca idahoensis and Artemisia tridcnlata

33

Comparison of habitat use by sheep and goats:~\n reviewing the literature on habitat use by
sheep and goats, it was difficult to make comparisons between the two species because
habitat types identified by the authors were not standardized. In general, data from the
various separate studies of habitat use indicate extensive resource overlap for goats and
sheep. In the general category of "grass", goat use averaged 56% for two studies (Smith 1976;
von Elsner-Schack 1 986) and sheep averaged 54 % use for three studies (Oldemeyer et al. 1971;
Frisina 1974; Tilton and Willard 1982). The use of "tree" type habitat was also similar: 36%
for goats (Peck 1972; Adams and Bailey 1980) and 27% for sheep ((Oldemeyer et al. 1971;
Tilton and Willard 1982). Use of "rock" habitat did differ with goats spending an average,
based on four studies, of 47% of their time (Peck 1972; R.W. Thompson 1981; Adams and
Bailey 1980; von Elsner-Schack 1986) while sheep only averaged 21% (Oldemeyer et al. 1971;
Frisina 1974; Tilton and Willard 1982). It must be stressed these averages and any
conclusions drawn from them, are tenuously based on general habitat classifications that
were assumed, but not known, to be similar among these studies.

Few studies were found where habitat use by sheep and goats was studied
simultaneously. Chadwick (1974) found some habitat segregation but did not quantify the
differences. Geist (1971) found goats in the winter preferred cliff areas more than sheep;
goats spent approximately 52% of their time in sheer cliff areas while sheep only spent 28%
of their time in these areas. In two studies of bighorn sheep, Stewart (1975) and Pallister
(1974) also recorded habitat use by non-native goats on their study areas. Stewart divided
the study area into a series of habitat/ topographic subtypes. His findings of sheep and goat
use of these subtypes are in Table 12. Pallister also divided his study area into habitat
subtypes but used different classifications (Table 12). Overlap indices derived from Stewart's
and Pallister's data (Fig. 6) indicate a high amount of habitat segregation.

Figure 6. Niche overlap indices for habitat selection by sheep and goats. The indices are based on data from Table 12 for the
comparative studies by Pallister (1974) and Stewart (1975)

1.0

X

CD

-a

G

a

CO

~C

>
o

0.5

0.0

YZZA Pallister (1974)
Stewart (1975)

Winter

Summer

34

Tabic 13. Selection of physical habitat characteristics by sheep and goats. Distance to escape habitat values are the maximum distance
in which at least 80% of the animals were found. Values for slope and elevation are the means of data reported in the literature.

Sheep

Goals

Summer

Winter

Summer

Wii

Distance to escape habitat:

Frisina (1974)

140 m

140 m

Fox (1983)

300m

Pallister(1974)

140 m

550 m

McFelridge (1977)

300m

Oldemeyer et al. (1971)

100 m

Hjeljord (1971)

275 m

Whitfield (1983)

100 m

Smith (1986)

400 m

Martin (1985)

100 m

Thompson, R.W.(1981)

250m

Tilton & Willard (1982)

-

320 m

Mean

120 m

278 m

Mean

305 m

Slope (degrees):

Frisina (1974)

23"

31°

Kuck (1970)

60°

Pallisler (1974)

19°

18°

Chadwick (1977)

40°

Whitfield (1983)

17°

Smith (1976)

48°

49°

Martin (1985)

29°

24°

Thompson, R.W. (1981)

50°

Hayden (1989)

27°

31°

Mean

22°

24°

Mean

41°

47°

Elevation:

Frisina (1974)

1687 m

1690 m

Adams & Bailey (1980)

3050 m

Pallisler (1974)

2867 m

2180 m

Thompson, M.J. (1981)

2256m

2256 m

Whitfield (1983)

3034 m

3033 m

Smith (1976)

2441 m

1756 m

Martin (1985)

3035 m

2822 m

Thompson, R.W. (1981)
Hayden (1989)

3700 m
2800m

Mean

2655 m

2431 m

Mean

2799 m

2354 m

Reed (Colorado Division of Wildlife, Ft. Collins, CO; unpubl. data) specifically tested
habitat use by sympatric native sheep and introduced goats in Colorado. He identified 25
alpine habitats and recorded frequency and intensity of use. His data were not available for
calculation of an overlap index. However, in general, he found goats were more selective in
habitat use than sheep and the two species rarely selected the same habitat types
simultaneously.

Based on the findings of Pallister (1974), Stewart (1975) and Reed (unpubl. data), there
was significant separation in habitat use between sympatric sheep and goats. This separation
in habitat use is likely a major factor in the coexistence of sympatric native goat and sheep
populations. The occurrence of habitat separation in these three studies indicates goats and
sheep will also likely coexist when goats are exotic introductions, unless sufficient habitat
restriction for sheep has occurred (Adams et al. 1982b).

Another area of potential competition between goats and sheep is for the physical
environment. Several investigators have quantified habitat use by goats and sheep relative
to elevation, slope, and distance from escape terrain. Table 13 summarizes the findings of
these studies. There was no difference in mean elevation used by goat and sheep. However,
the average degree slope used by goats was significantly steeper (F = 15.19, P < 0.01) than

35

for sheep. Distance to escape terrain was significantly less for sheep than goats (/ = 6.04, P
< 0.01). Thus goats preferred steeper slopes but explored further from escape terrain than
sheep.

A major factor in different habitat use by sheep and goats, primarily in the winter, is the
greater tendency of sheep to migrate longer distances to winter range than goats (Rideout
1977; Martin and Stewart 1980). This tendency is most evident in Yellowstone Park where
sheep have distinctive traditional wintering areas (e.g. Mt. Everts). When spatial separation
exists during winter, e.g. YNP, the effect of goats on sheep would be less than when such
separation may not occur, e.g. GTNP.

Population trends in sheep:-ln assessing possible effects of goats on sheep in the future,
it is of value to summarize past and current estimates of sheep populations in the potentially
affected areas. In Yellowstone Park, sheep on the north range would be the first to be
impacted by goats. Numbers of bighorn sheep in the northern section of Yellowstone Park
have been estimated since 1903. Buechner (1960) summarized population estimates from 1903
to 1955 and Woolf (1968) added estimates to 1966. Oldemeyer et al. (1971) censused sheep
in 1965-68. Houston (1982) presented population figures up to 1978. The methods used to
estimate numbers have changed through the years and the accuracy of the methods likely
varies. Table 14 summarizes population estimates for the north range from 1903 to 1981. In
1981 there was a outbreak of pinkeye (Chlamydia sp.) in the sheep on the Mt. Everts winter
range in Yellowstone Park. Approximately 300 of the 550-600 animals on the north range
were exposed and mortality was estimated to be approximately 50 animals (Meagher, unpubl.
Park Service data). The effect of the outbreak seems to have been localized and short term.

Table 14. Summary ol winter population estimates of bighorn sheep on the north range of Yellowstone Park.

Year

Number

Year

Number

Year

Number

Year

Number

Year

Number

1903

100

1926

217

1936

118

1949

144

1970

384

1905

100

1927

346

1937

175

1955

192

1971

227

1907

200

1928

170

1938

181

1956

121

1972

373

1911

250

1929

77

1939

219

1961

118

1973

332

1912

210

1930

125

1940

272

1962

148

1974

446

1916

200

1931

101

1941

200

1965

222

1975

404

1922

233

1932

86

1943

138

1966

229

1976

426

1923

200

1933

82

1945

203

1967

231

1977.

430

1924

217

1934

125

1946

176

1968

257

1978

471

1925

195

1935

126

1948

176

1969

295

1981

550*

'M. Meagher (Personal Communication)

Buechner (1960), Oldemeyer et al. (1971), Keating (1982), and Martin (1985) present data
on specific herds and /or bands of sheep within the northern range. Additionally, Mills
(1937) presented winter estimates for various locations in the Park. Several of these divisions
represent sheep numbers in the northeast corner of the Park where goats presently occur.
If sheep numbers are affected by future increases in goats, these sheep bands would be the
first to exhibit population changes. The data of Mills (1937), Buechner (1960), Oldemeyer et

36

al. (1971), and Martin (1985) are summarized in Table 15 for use in future comparisons.
Martin (1985) also estimated summer populations in 1978-79 of approximately 75 sheep in
the Wolverine /Cutoff Peaks area and 40 sheep in the Amphitheater Peak region.

Table 15. Summary of winter population estimates (or specific herds or bands of sheep in the north range of Yellowstone Park

Herd 1935 1955 1965 1966 1967 1968 1970 1972 1974 1976 1977 1978 1979 1981 1982

95 132 190 202 190 220 220 190

109*

Ml. Everts

106

36

48

50

44

76

Yellowstone River

Reese Creek

7

6

5

2

7

Deckard Flats

67

42

44

43

40

Specimen Ridge

28

27

34

48

47

56

Soda Butte Creek

Druid Peak

28

36

30

60

43

Mt. Norris

9

20

24

15

19

Barronette Peak

2

11

12

9

1

Abiathar Peak

16

25

16

11

15

Wolverine Peak

Soda Butte

30

Cottonwood

7

Oxbow Crags

5

Turkey Pen

15

Daly Creek

35

'M. Meagher (Personal Communication)

There are no long term surveys of sheep populations in Grand Teton National Park. The
general consensus is sheep population in Grand Teton has continually declined since
settlement of the adjacent valleys (Whitfield 1983). Buechner (1960) reported a population
of 21 animals in 1954 for the "Teton wilderness". Whitfield (1983) reported minimum
population estimates of 70 in 1969, 71 in 1976 and 62 in 1979. Whitfield(1983) speculated the
actual population in 1981 was approximately 125 sheep. The main factor limiting sheep
numbers in Grand Teton is the loss of low elevation wintering areas (Whitfield 1983).

HISTORICAL AND PREHISTORICAL OCCURRENCE OF MOUNTAIN GOATS

- Critical to the discussion of mountain goats is their historical status in the Yellowstone
Ecosystem. If goats occurred in the Yellowstone area in the historical past (250-0 years B.P.),
then they would not be considered exotic and the movement of goats into Yellowstone and

37

Grand Teton Parks, regardless of their origins, could be considered an establishment of an
extirpated native species.

On a historical scale, the presence of goats in the Greater Yellowstone Ecosystem cannot
be confirmed. The earliest whites to travel into the Greater Yellowstone Ecosystem were
Spanish explorers in the mid 170(Xs (Nasatir 1952). However, these earlier explorers recorded
little concerning wildlife species seen. The earliest explorers of the region who kept detailed
accounts were Lewis and Clark in 1804 to 1806 (DeVoto 1953). Their course skirted north of
Yellowstone Park but their journals were reviewed for possible references to the Yellowstone
area. Burroughs (1961) summarized all the references to wildlife Lewis and Clark made
during their journey. The first time mountain goats were mentioned was when Clark sighted
one as the expedition crossed the continental divide near Lemhi Pass, 190 km west of
Yellowstone Park. This area is recognized historic goat range (Hall 1981). Goats were not
mentioned again until Lewis and Clark reached the east side of the Cascades. When the
expedition reached the west coast, they were brought skins of goats and Lewis mentioned
one of soldiers commented on seeing similar animals when they were near the "black hills
where the little Missouri passes them...". It is assumed this is in reference to the Black Hills
of South Dakota. However, there is less evidence goats historically occurred in that range
and this reference likely represents a misidentification. Throughout Lewis' and Clark's
journals, references are made to "goats" but it is widely accepted these remarks refer to
pronghorn antelope (Antilocapra americana) (Burroughs 1961).

After the expedition of Lewis and Clark, others ventured near and into the Yellowstone
area. The main white visitors to the area up to the mid ISOO's were hunters and trappers.
However, few reported on what wildlife they saw or caught. One of the few men to spend
an extended period of time (1834 to 1843) in the Yellowstone area and write about it was
Osborne Russell (Haines 1969). During his extensive travels in the area in connection with
the fur trade, Russell recorded seeing a variety of wildlife but never mentions seeing
mountain goats. After Russell's accounts and to the late 1800's several private and
government sponsored expeditions were made (Raynolds 1868; Doane 1871; Jones 1875;
Ludlow 1876; Roosevelt 1893; Chittenden 1895) to the Yellowstone area but again, none
mention seeing mountain goats. In the early 1900' s, Skinner (1926) reviewed the literature
and talked to various hunters, rangers, and guides who were familiar with the area at that
time. He concluded mountain goats were not historically in Wyoming, including the
Yellowstone area. Thus, in the recent history of the Yellowstone Ecosystem, evidence of
goats being part of the faunal complex is lacking.

There are also no records of prehistorical (< 12,000 years B.P., approximate time of
human occupation of North America (Martin 1967)) occurrence of mountain goats in the
Ecosystem. Excavations of Mummy Cave (9,000 years B.P.) (McCracken et al. 1978), 19 km
east of Yellowstone Park and of Lamar Cave (1,700 years B.P.) (Hadly 1990), in northern
Yellowstone, notably lack goat remains.

It can be argued the lack of historical and prehistorical evidence is not conclusive proof
goats were not present in the Ecosystem during those times (Lyman 1988). Most early
explorers of the Yellowstone area traveled in the valleys, rarely scaling the high peaks where
goats would have lived. Likewise, the few archeological/paleontological excavations of
recent sites (< 10,000 years B.P.) (McCracken et al 1978; Hadly 1990) were in valleys.
However, unless conclusive evidence is found, it seems likely mountain goats were not

38

present in the Yellowstone area at the time of arrival of Europeans and possibly not present
for several thousand years prior to that time.

In contrast to historical and prehistorical data, there is ample published evidence
mountain goats ranged well south and east of the Yellowstone area during the late
Pleistocene (15,000 - 10,000 years B.P.) and before (Sinclair 1905; Stock 1918 & 1936; Wilson
1942; Guilday et al. 1967; Anderson 1968; Mead 1981; Logan 1981; Walker 1982).
Additionally, several fossil mountain goat specimens were collected in the Greater
Yellowstone Ecosystem from the Palisades reservoir area in Idaho from 70,000+ years B.P.
deposits (S. Miller, Idaho Museum of Natural History, personal communication). Figure 7
summarizes the known Pleistocene sites of Oreamnos sp. records.

Figure 7. Locations of known paleontological sites where mountain goat (O. americanus or harringtoni) remains were found
(Harris 1985).

# Oreamnos americanus
Oreamnos harringtoni

- Little Canyon Cr

- Little Box Elder Cave

- Bell Cave

- Horned Owl Cave

- Palisades Reservior

- Smith Creek Canyon

- Rampart Cave

- Tse'an Bida

- Stanton Cave

10- Muskox Cave

11- San Josccilo Cave

12- Samwel Cave

39

With the advance of the Cordilleran ice sheet (Waitt and Thorson 1983), goats were
forced to southern refugia (Harington 1971). During that time, fossil evidence indicates O.
americanus extending as far east as southeastern Wyoming (Fig. 7) and a smaller species O.
harringtoni extending into east-central Mexico (Fig. 7). The dispersal route of goats to the
east, in advance of the ice sheet, is hypothesized as being through the Greater Yellowstone
Ecosystem (Mead 1983). During the same time, extensive mountain glaciation existed south
of the Cordilleran sheet terminus (Porter et al. 1983) and covered much of the Greater
Yellowstone Ecosystem. The presence of fossil goat remains in the Palisades, Idaho area
supports Mead's (1983) hypothesized migration route through the Yellowstone area. These
specimens represent habitation of the area well before the last advancing mountain glaciers
but goats had to have either inhabited the Yellowstone area, or move through it, prior to the
last advance of the Cordilleran ice sheet (20,000-18,000 years B.P.). It is unknown if goats
recolonized the area after recession of the glaciers. Regardless, there is irrefutable evidence
mountain goats were Pleistocene inhabitants of the Yellowstone area.

A factor germane to determining the exotic or native status of present day goats to the
Ecosystem is their taxonomic relationship to the prehistoric and Pleistocene mountain goats.
If modern goats are significantly different from their ancestors, then considering them native
to the Ecosystem is as incongruous as concluding modern camels and horses are native to
an area because of the Pleistocene occurrence of ancestral forms. Based on taxonomic
analyses, investigators identify all the fossils found in Wyoming as O. americanus. Thus,
modern forms of mountain goats are not exotic to the Yellowstone area on a late Pleistocene
basis. Additionally, based on discussions presented relative to recognized native floral and
faunal components of the Yellowstone Ecosystem, goats could also not be considered
ecological exotic. Goats co-occur in other climatologically and physiognomically similar areas
with most, if not all, the recognized native faunal and floral species of the Yellowstone area.
Thus, given the Pleistocene occurrence of goats, native plants and animals of the Yellowstone
area have had an evolutionary past that might included mountain goats.

What is unknown is how long ago goats were extirpated from the Yellowstone area and
what caused their extinction. If goats were indeed not present historically (250-0 years B.P.),
at what time between their Pleistocene occurrence and 250 years B.P. did they become
extinct? Did goats fail to colonize the Yellowstone area after the glacial ice receded? This
seems unlikely as they would have had to move back through the area to repopulate more
northern areas. If colonization occurred, was extinction a random event (Newmark 1987) or
result from overharvest by aboriginal people (Martin 1967)? Palynological records from the
Yellowstone area (summarized in Hadly 1990) indicated a warming trend between 9,000 and
5,000 years B.P. Possibly this postglacial warm period caused a recession of goat ranges
northward of the Yellowstone area. If mountain goats have slow dispersal rates (Stevens
1983), the current historical range may represent a re-advance southward with the return of
a cooler climate; an advance possibly interrupted by the arrival of Europeans. Given time,
goats might have eventually moved back into the Yellowstone Ecosystem, as they may
presently be doing from historic range into the Centennial Mountains. Currently, all this is
speculation and the rapid expansion of goat range in the mountains north of Yellowstone
Park would tend to contradict this hypothesis. Perhaps discovery and excavation of other
paleontological/archeological sites within the Yellowstone area will answer many of these
questions.

40

Park Service personnel must decide if sufficient time has elapsed since extirpation to
classify goats entering the Park as exotic. If the Park Service classifies goats as native to the
Yellowstone Ecosystem, no action would be required and goats would be allowed to become
established in both Parks. If goats are classified as exotic, Park personnel will need to
develop a management plan relative to their eventual establishment in the Parks. The
following section is provided as a guide to the development of such a plan.

MANAGEMENT ALTERNATIVES

Based on what has been presented, there are three possible scenarios for goat populations
in Yellowstone and Grand Teton National Parks. In the first, the status of goat populations
in the Parks would remain approximately the same. The populations would primarily consist
of transitory or ephemeral individuals with some animals persisting in limited areas along
the border of Yellowstone Park, In the second scenario, goats would become established in
the interior of both Parks but be at relatively low population densities. Under this scenario,
an approximate population of 100 animals would inhabit Yellowstone Park and
approximately 160 animals would be in Grand Teton Park. The third scenario predicts higher
numbers of goats for both Parks. Approximately 500-550 goats would be in Yellowstone and
Grand Teton Parks. At this time, it is difficult to predict which of the three scenarios is most
likely to occur. If the first scenario proves accurate, there would be no need for Park
personnel to develop a management strategy. Thus, in assessing management alternatives,
only the low and high population scenarios will be addressed.

Goats are currently not significantly impacting the fauna and flora of either National
Park. However, under the low population scenario for Grand Teton Park and the high
population scenario for both Parks, some negative impacts could be realized. Three
alternatives exist for managing mountain goats in the Parks: No action, selective control of
goats at a predetermined population level, and total elimination of goats within Park
boundaries. These alternatives will be assessed relative to impacts on Park ecosystems, Park
visitors, and the National Park Service. Additionally, estimated costs of each action will be
analyzed. These categories parallel those used by personnel of Olympic National Park
(1987a).

No Action

Impacts on the ecosystem-Surveys of goat range in Glacier National Park, Montana and
Mt. Baldy, Idaho with high densities of goats indicate little physical damage and percent
cover of grass and forbs comparable to similar habitat in Yellowstone Park. Based on these
surveys, goat densities in both Parks, even at high population estimates, would likely not be
high enough to significantly impact the physical or floral components of the Parks.

If numbers of goats in Yellowstone Park increase, the area to be initially impacted would
be Wolverine Peak. Monitoring of the photo points established in that area would help
assess any impact goats might have on the floral component of the Park.

. Establishment of goats in both Parks would be within existing bighorn sheep range. At
both the low and high population estimates, some impact of goats on sheep would be
expected. The extent of the impact would depend on the degree of overlap in food and
habitat use by sheep and goats. Data indicate food habits of sympatric sheep and goats

41

diverge, especially in winter. Habitat use by both species also overlap but again, in
sympatry, some separation seems evident. The differences in winter food and habitat use
goats and sheep results mainly from differing wintering patterns. Sheep will often travel to
traditional winter ranges well apart from summer ranges; goats more often concentrate their
winter movements within or near their summer range. Indications are such movements are
typical for sheep in Yellowstone Park. The result is a reduction in completion during the
most critical time of the year. In the mountains north of Yellowstone, there is no evidence
sheep populations have decreased as a result of increasing numbers of goats (Frisina 1974;
Stewart 1975). Consequently, under the low population scenario, it is predicted goats will
have little to no impact on sheep in Yellowstone Park.

Under the high population scenario, an estimated 500-550 goats would inhabit
Yellowstone Park, likely in much of the existing sheep range. This number of goats is higher
than current levels of bighorn sheep and such an increase in goats would likely be at the
expense of sheep numbers. At this time, it is difficult to estimate the proportions of goats
and sheep that might occur at an equilibrium. Goats and sheep co-exist at relatively high
numbers elsewhere in the West. However, carrying capacities for both species likely differ
between these areas and Yellowstone Park. Some ecological separation of the two species,
especially in the winter, would be expected. If mountain goats exclude sheep primarily from
summer range, their impact would be less than if they established themselves in major sheep
winter ranges such as Mt. Everts. Because of these uncertainties, it is difficult to predict the
exact impact goats would have on sheep.

In Grand Teton Park, the sheep population is considered extremely low compared to
historic estimates and is viewed as a remanent population (Whitfield 1983). Sheep in the
Park use combined winter and summer ranges (Anonymous 1987b) because traditional winter
range was lost to human development (Whitfield 1983). Assuming that establishment of and
increases in goats would occur on the present combined range of sheep, some negative
impacts could be expected even at the low population estimate. These negative impacts
would be exacerbated at higher goat numbers. Competition for food and habitat in the
summer may not prove critical. However, areas where sheep winter in the Park would likely
also be attractive to goats. Based on the literature, (Pallister 1974; Stewart 1975; Dailey et al
1984; Reed 1986) minimal overlap of resource use and agonistic interactions in such a
situation would be predicted. However, because of the compressed winter range of sheep,
competition for food and shelter could be more intense than what is indicated by the
literature (Adams et al. 1982b). If this management option is chosen, intensive monitoring
of goat-sheep interactions should be carried out.

Impact on human use— With the current status and distribution of goats, most visitors to
Yellowstone and Grand Teton Parks are unaware of the goats in the Parks. Under both the
low and high population estimates, goats would invade interior parts of the Parks and
become more readily visible. Sightings by hikers, campers, and day visitors would increase.
These sightings would likely be viewed favorably by most people. Goats are considered by
many as charismatic megafauna, characteristic of wild areas. Sighting of goats is considered
an enhancement to the outdoor experience. Mountain goats in Glacier National Park are
considered the main species to view while visiting the Park and souvenir stores stock a wide
variety of goat paraphernalia. It is likely that goats in Yellowstone and Grand Teton would
initially receive similar favorable public support, regardless of population levels.

42

In Olympic National Park, goats habituated to humans and developed a "fondness" for
salty foods and human sweat (Anonymous 1987a). The goats often became nuisances and
at times aggressive in their pursuit of these items, detracting from the outdoor experience.
Other Parks, in particular Glacier Park, do not have similar problems and none are
anticipated in Yellowstone or Grand Teton Parks unless goats become established in high
human use areas, e.g. Mt. Washburn.

Impact on Park Service:— The Park Service has the charge "to perpetuate the native animal
life..." of National Parks and not allow exotic species "to displace native species if this
displacement can be prevented by management" (Anonymous 1988). If mountain goats are
considered "exotic" because they historically did not inhabit the Greater Yellowstone
Ecosystem, the Park Service would have to develop a management plan, including possible
eradication, depending on whether goats "... threaten Park resources...". At the low
population estimate for goats in Yellowstone, minimal impact on plants and animals is
expected. Thus, the presence of goats would not violate any management mandates and
action by the Park Service would not be necessary. The Park Service would receive favorable
comments from visitors who sighted goats. These favorable responses could enhance the
Park Service's public image.

At the high population estimate, goats would become a prevalent component of
Yellowstone's wildlife. Assuming no negative interactions between goats and humans, public
support would remain favorable. However, with the higher densities of goats, there may be
negative effects on the bighorn sheep populations. The Park Service would then have to
decide if the impact is sufficient to warrant initiation of control measures.

In Grand Teton National Park, the Park Service would receive the same favorable
response from the public as in Yellowstone. However, even at the low estimate of goat
numbers, negative impacts on sheep are possible. Depending on the severity of the impacts,
the Park Service may have to develop a management plan for goats.

Cosf:-With this alternative, there would be no cost in managing goat numbers. The only
cost incurred would be for research and monitoring of goats. Research projects could
include: 1) a study of goat and sheep interactions in the Wolverine Peak area of Yellowstone
Park and 2) a detailed comparative study in northern Yellowstone of vegetation in areas with
and without goats.

Monitoring activities should include: 1) periodic sampling of permanent photo points on
Wolverine Peak (YNP), 2) aerial surveys for goats in likely habitat areas to determine
population trends, and 3) annual census of bighorn sheep, especially in Grand Teton Park,
to monitor potential effects of goats on sheep.

Selective Control of Goats

Impacts on the ecosystem:-\J nder this management option, some predetermined population
level and /or distribution pattern of goats would be selected. The population level chosen
should be below the level at which negative effects on faunal or floral components of the
Park become apparent. This would seem like a postori planning but if the low population

43

scenario proposed proves to be accurate and no negative impacts on native fauna and flora
are realized, little or no control of goats would be needed.

Management of the specific distribution of goats in Yellowstone Park would have to be
on a range by range basis. Control in certain areas may be warranted regardless of the
overall population level in the Park. As previously mentioned, some locations in Yellowstone
Park might support higher numbers of goats than others and produce negative impacts.
Control would be needed to maintain acceptable numbers in these areas. Additionally, if
goats should invade major wintering areas of sheep, for example, Mt. Everts, they may
adversely affect sheep survival, even at low numbers. In such cases, minimal numbers or
total removal from those areas would be warranted.

In Grand Teton Park, the number of goats projected by the low population scenario could
negatively impact sheep because of their compressed winter range. However, because of the
monetary and social implications of any control measure, a conservative approach is still
advised. Under this management option, it would not warrant the expenditure of time and
resources to control goat numbers until or unless they reach a level where they begin to
negatively affect the sheep population or the habitat.

Impact on human uset-The potential impact of control measures on human use of the
Parks will depend on the population level of goats selected. If the level is at or near the
predicted low population scenario and that scenario proves accurate, the impact would be
as outlined under the no action management plan. Maintenance of population levels between
the low and high population scenarios would have intermediate impacts. The extent of the
impacts would be a deciding factor in establishing a particular population level for a specific
location. For example, an equal density of goats on Mt. Washburn, an area of high human
use, might have different impacts on Park visitors than an area of light use such as Mt.
Holmes. Goats might become more habituated to humans on Mt. Washburn and become a
nuisance. In this situation, a lower density of goats on Mt. Washburn might be appropriate.

Control of goats below a natural equilibrium will require removal of excess individuals.
Impact of removal on human use of the Parks will depend on the removal methods used.
Removal methods and their impacts will be discussed in detail later.

Impact on Park Service:— Maintenance of any level of goats in the Parks would impact Park
Service policy regarding exotic species. As per the policy (Anonymous 1988), the target
density of goats selected by Park personnel would be sufficiently low to prevent negative
impacts on native species. Maintenance of low to moderate levels of goats within Park
boundaries would likely not negatively impact the public's perception of the Park Service.
Selection of this management option would require the Park Service to initiate several long
term monitoring programs. Annual surveys would be needed to determine goat numbers
and distributions. Such surveys would also be needed to monitor the population status of
bighorn sheep. Vegetation sample plots such as those established during this study would
have to be set up in other areas of the Parks where goats might become established.

If goats reach a level at which control is needed, the Park Service would have to initiate
a removal program. The specifics of such a program will be discussed later. Removal of
goats, depending on the method, may create a negative public image of the Park Service.

44

Costs:-The selection of this management option would require annual funding of the
monitoring programs established. Existing Park personnel could conduct these programs but
this would divert time and effort from current functions. Alternately, specialized personnel
on loan from regional state or federal resource agencies could conduct these programs.

If goats reach the preselected population level, Park personnel would have to remove
excess goats by capturing and relocating or shooting individuals. The cost of removal is
dependent on the type of capture technique used. Personnel at Olympic National Park
developed a simplified comparison of various control techniques (Anonymous 1987a) (Table
16). The various techniques listed are applicable to Yellowstone and Grand Teton Parks and
costs per method are realistic. Initiation of a control program would require long term
commitment of funds for annual or periodic removal operations.

Table 16. Comparison of capture and control technique* for goats (From Anonymous (1987a)).

Technique i

Precapture
Requirements

Sensitivity

Multiple
Capture

Safety
Personnel

Safety
Goats

Relative
Efficiency1

Cost per
Animal2

Fool Snare

Minimal

Good

No

Good

Good

Poor

$50-100

Drop Net

Extensive

Good

Yes

Good

Good

Fair

$300-500

Aerial Net Gun

Minimal

Excellent

No

Fair

Poor

Good

S800-1000

Ground Darting

Minimal

Excellent

No

Fair

Fair

Poor

$200-400

Aerial Darting

Minimal

Excellent

No

Good

Fair

Good

S600-400

Drive Net

Extensive

Poor

Yes

Fair

Poor

Poor

$900-1000

Aerial Shooting

Minimal

Excellent

N/A

Good

N/A

Good

$30-50

Number of captures per unit effort.
2Excludes transportation costs.

Elimination of Goats Within Park Boundaries

Impacts on the ecosystem:-Excep\. for the few animals on the northeast boundary of
Yellowstone Park, there are currently no established populations of goats in either Park.
Thus, maintaining goat-free Parks would require removal of all goats as they enter the Parks.
Removal of goats as they enter the Parks would require capture operations when and where
goats become established. Depending on the removal method used and the location of the
operation, some negative impacts could result. Methods requiring intensive manpower or
ground equipment would increase human impact on an area. Locations currently readily
accessible to humans would not experience as much of an impact as would more remote
wilderness areas.

Impact on human use:— Currently, sightings of goats by visitors to both Parks are sporadic.
Most Park visitors do not know goats are present or periodically enter the Parks. Thus,

45

removal of existing goats and future immigrants will not be noticed by Park visitors.
Depending on the removal method chosen, most visitors would also not be aware of removal
activity. High profile removal methods would likely arouse the curiosity of Park visitors.
However, visitor awareness would be minimal because most sightings and consequently
removal operations are in more remote locations in the Parks.

Impact on the Park Serace:-Selection of this option would require periodic surveillance of
likely locations of goat colonizations. It would also require checking every reported goat
sighting and removal action if the sightings were verified. Because of current distributions
of mountain goat populations in the Greater Yellowstone Ecosystem, the selection of this
management option will require a long term commitment of resources and personnel to
removal activity by the Parks.

At Yellowstone Park, there are major concentrations of goats juxtaposed to Park
boundaries. These populations are under the jurisdiction of the Montana Department of Fish,
Wildlife and Parks and the Wyoming Department of Game and Fish. Introductions of goats
into these areas were intentional and main management efforts are to maintain or increase
goat numbers. Total long term elimination of goats from Yellowstone Park is not likely
because of consistent re-invasion of the Park by dispersing individuals from these reservoir
populations.

At Grand Teton Park, the major concentration of mountain goats is approximately 40 km
south of Park boundaries near Swan Valley, Idaho. This population of goats is under the
jurisdiction of the Idaho Department of Fish and Game. To date, these goats have not
extended their range significantly from the original transplant areas. There have been
sightings of goats in the areas between current goat range and Park boundaries. These
sightings are sporadic except for consistent reports of a few goats just south of the Park on
Taylor Mountain. Because of the distance between the reservoir population and Grand Teton
Park, keeping the Park goat free will not be as difficult or time consuming as in Yellowstone.
If there are any goats currently within Park boundaries, re-invasion by new individuals after
their removal would not likely reoccur very rapidly. However, if goat populations eventually
become well established near the Park boundaries, persistent re-invasion of Grand Teton Park
would necessitate constant surveillance and removal operations.

Cosr:~This management option would commit the Park Service to long term control of
a large ungulate species. Both Parks would have to make a long term commitment of funds
and personnel for periodic surveillance of likely colonization sites and checks of reported
goat sightings. The Parks would also have to maintain sufficient funds and resources for
removal of any goats found within Park boundaries. Amounts and consistency of funding
would depend on the rate of re-invasion, Presently, costs of this option would be greatest
for Yellowstone Park. However, if goat populations become established just outside of Grand
Teton Park, costs to Grand Teton could be higher because the more rugged terrain would
make removal more difficult than in Yellowstone Park.

Other Alternatives

Besides the three management options considered, there are several other alternatives
that exist. Control or removal of goats from the Parks could be accomplished by opening the

46

Parks to public hunting. Grand Teton Park currently has a controlled hunt on elk {Ceruus
elaphus). However, this hunt is presently under review because National Parks are not
normally open to public hunting. Thus, this option is not deemed feasible.

The potential of re-introducing wolves into the Greater Yellowstone Ecosystem is being
investigated (Anonymous 1987c). If re-introduction occurs and wolves become well
established in Yellowstone and Grand Teton Parks, some loss of mountain goats to wolf
predation is likely to occur. However, given the high densities of other ungulates in the
Parks, it is unlikely predation levels on goats would be sufficient to control their numbers.

REMOVAL METHODS

The 2nd and 3rd management options require removal of goats from the Parks. There
are several removal methods available and their feasibility for use in a National Park setting
has been addressed by personnel in Olympic National Park (Anonymous 1987a). The
methods include sterilization, live capture and shooting. Sterilization was considered to be
the least feasible of the three methods because of its difficulty in administration and duration
of effect (Anonymous 1987a) and will not be discussed further.

Live capture of animals can be accomplished by several methods ranging from foot
snaring to drive nets. Personnel from Olympic Park (Anonymous 1987a) assessed the
advantages and disadvantages of the various live capture techniques. Their assessment is
reproduced in Table 16 (Pg 45). Each technique has advantages and disadvantages
depending on the terrain, the number of animals needed to capture, and cost. Some
techniques are better adapted to capture of one or two animals while others are more efficient
for capturing large numbers. Some techniques will only work in specific terrains. Capture
of goats in the Parks would involve differing numbers of goats and be in a variety of terrains.
Because of the differing circumstances that might arise, no one method of live capture is
being recommended at this time. All the methods are presented as a guide to technique
selection if the decision to remove animals is made.

Regardless of the removal method, the Park Service would have to dispose of the animals
captured. Currently, state resource personnel in various western states have active programs
for re-introducing mountain goats into historic ranges. The Park Service would have to make
arrangements with these agencies on the transport of captured goats to designated sites. As
control of goats would be an ongoing operation, it is uncertain how long state agencies
would accept goats before their re-introduction plans are complete. If state agencies would
no longer need excess goats, the Park Service might have problems disposing of the animals
they capture.

The logistics of live capturing animals would also vary considerably. All the techniques
would require either capture or removal of animals from the mountains with helicopters.
Park personnel would have to establish staging areas for helicopters to land and trucks to
load captured animals. Some environmental damage would be expected in such areas. The
amounts of helicopter noise and truck traffic would vary with the intensity of the operation.
Moderate to intensive operations might negatively impact human use of the Park, especially
in back country areas. The impact could be reduced by timing the operations in early spring
or late fall when visitor use of the Parks is lower.

The third removal technique is shooting of mountain goats. Park employees or federal
animal control agents would be responsible for shooting animals. Dead animals could be left

47

where shot, buried, or removed. If Park personnel remove the carcasses, they would have
to dispose of them in line with Park Service policy.

The impact on the environment of shooting goats should normally be minimal. If Park
personnel use helicopters, they can operate from airports in nearby towns. Leaving the
carcasses to decompose would not differ much from natural mortality, if only a few animals
are involved. Shooting large numbers of animals would necessitate removal or burial of the
carcasses. Removing the carcasses could be accomplished with horses or by helicopter with
a minimal impact on vegetation.

Shooting of goats could have an extensive negative impact on the Park Service. As
previously mentioned, mountain goats are viewed favorably by the general public. The
public's reaction to killing of goats within Park boundaries could be extremely vocal and
negative. The media would likely not portray the Park Service in a very positive light.

Actual shooting operations should not impact human use of the affected areas. In the
more remote areas of the Parks, few people would be aware of the operations. Closing of
back country areas to hikers when operations are to be conducted and /or conducting
operations in early spring or late fall would further reduce the impact on human use. In
areas more frequently used by visitors, shooting of goats would have to be done in late fall,
winter, or early spring and all animals killed would have to be removed.

In summary, the various impacts of the three management alternatives considered are
summarized in Table 17. The "no action" management option is the least expensive; selective
control and elimination of goats will require long term commitment of personnel and funds
for removal of excess goats from the Parks. If populations of goats in either Park only
increase to the low population estimates, the no action management option also has the least
negative impact on human use of the Parks and the Park Service. Initiation of control
measures, either non-lethal or lethal, will likely result in some negative impacts on human
use and the Park Service image. No negative impact on Park vegetation is anticipated under
the "no action" option even at the high population estimate. Some localized impact is
expected under both "selective control" and "elimination" plans. If estimates of future
population levels of goats are in error, however, the no action option could have the greatest
negative impact on bighorn sheep in both Parks.

RECOMMENDATIONS

The first decision Park Service personnel must make concerns the status of goats in the
Greater Yellowstone Ecosystem. No evidence was found that goats were part of the historic
fauna but, data indicate goats were at least late Pleistocene transients through the area.
Consequently, regardless of timing and causes of extirpation, goats are not prehistoric exotic
of the Greater Yellowstone Ecosystem. Park personnel must decide if sufficient time has
elapsed since extirpation to classify goats as historical exotic. This presents a complex issue
and would likely require a review of the concept of what constitutes an exotic species.
Because of the complexity of the issues involved, no formal recommendation is made at this
time. Needless to say, the decision made will greatly impact the Park Service's response to
the presence of mountain goats in both Parks. If goats are classified as native to the area,
then no further action is recommended; goats would be allowed to establish themselves as
part of the faunal complex of the Parks. If the decision is to consider goats exotic to the
Ecosystem, the following recommendations concerning management alternative are made.

48

Tabic 17. Summary of impacts of the three management plans presented relative to the two Parks.

Management
Alternatives

National Park Service
ixosyntem impacts Visitor Impacts Impjcis

YELLOWSTONE NATIONAL PARK

No Action
Low Scenario:

High Scenario:

Minimal impact on Favorable impact Minimal conflict

vegetation or sheep. Highly desirable with Park Service

species. policy. studies and surveys.

Minimal impact on Favorable impact Possible conflict

vegetation. Possible unless goats become with Park Service

impact on sheep. nuisances. policy.

Least expensive.
Cost only for selective

Same as for low
population scenario.

Selective control

Minimal impact on Possible noise and Attain Park Service 550-51 100/ animal

sheep. Some impact on visual intrusion. policy. Negative plus transportation,

vegetation in staging Negative impact on public opinion from Cost for periodic

areas. finding killed goats. noise/ dead animals. census of the populati

Elimination of Coats

Same as for
selective control.

Same as for
selective control.

Same as for
selective control.

$50-51100.' animal
plus transportation.
Costs for checking
goat sightings.

GRAND TETON NATIONAL PARK

No Action
Low scenario:

High scenario:
Selective control

Elimination of goats

Minimal impact on
vegetation. Possible
impact on sheep.

Minimal impact on
vegetation. Likely
negative impact on
bighorn sheep.

Minimal impact on
bighorn sheep. Some
impact on vegetation
of staging areas.

Same as for selective
control.

Favorable impact.
Highly desirable
species.

Favorable impact
unless goals become
nuisances.

Same as for
Yellowstone Park.

Same as for
selective control.

Minimal conflict
with Park Service
policy.

Likely conflict
with Park Service
policy.

Same as for
Yellowstone Park.

Same as for
selective control.

Least expensive.
Cost only for selective
studies and surveys.

Same as for low
population scenario.

550-51 100/ animal plus
transportation. Cost
will likely be higher
than for Yellowstone
because of the more rugged
terrain. Cost for periodic
census of the population.

Same as for

Yellowstone Park except
cost of capture likely
higher because of the
terrain.

49

Because of the uncertainty of eventual goat numbers, it is recommended Park Service
personnel develop a multi-level decision oriented management plan to respond to future
trends in goat populations. Considering the current number and distribution of goats relative
to the Parks, it is premature to initiate any control measures at this time. Thus the "no
action" management option is recommended as the initial stage (Fig. 8). Essential to the
implementation of such a plan is a long term commitment to monitoring goat and sheep
populations. Selection of appropriate management pathways would be keyed to future
trends in goat populations. If goats numbers continue to remain low, the "no action" policy
would stay in effect. If goat numbers reach a level where negative impacts are observed,
then an appropriate alternate control plan would be activated.

If removal of goats is required at some future date, the contingency plan recommended
is selective control of goats at an acceptable level. Elimination of goats from Yellowstone and
Grand Teton Parks is considered the least viable option. Large reservoir populations of goats
are currently near Yellowstone and would exist near Grand Teton Park if goat numbers in
that Park were high enough to cause problems. Because goats in these populations will
readily move in and out of Park boundaries, removal of all goats on the periphery of the
Parks would be impossible. Maintaining a goat-free Park interior would create an ecological
vacuum that would attract goats from outside of the Parks and necessitate constant
surveillance and removal activities.

Selective control of goats would involve removal of animals once a target density was
reached. If sufficient numbers of goats are removed, control operations would only be
conducted periodically. The presence of a resident number of goats in the Parks might also
reduce the immigration of animals from outside populations.

Regardless of the control option selected, it is recommended that such an option not be
initiated unless absolutely necessary. Both removal oriented management options would
result in severe negative public response and commit the Park Service to long-term cyclic
endeavors (Fig. 8). The no action option would require a long term commitment to
monitoring goat and sheep populations but such monitoring would still be less expensive
than control activities. This more conservative approach initially would give the Park Service
time to adopt a long term management plan such as the one suggested and, as importantly,
build public support, through education, for whatever plan is decided on.

In summary, if goats are classified as native to the Greater Yellowstone Ecosystem, no
further action would be necessary. If goats are classified as exotic, the recommendations of
this report are: 1) no action at this time, 2) monitor goat and sheep populations, 3) develop
alternate courses of action to respond to the different possibilities in future goat numbers,
and 4) develop a plan to build public support, and possibly input, for the course of action
to be taken.

50

Figure 8. Flow diagram for selecting management options relative to mountain goats in Yellowstone and Grand Teton Parks.

Yes

No
Action

No Action
Management Option

Monitor Mountain
Goat Populations

Choose a Control
Management Plan

Eliminate All Goats
From the Park

Selective Control
of Goats

Live
Trap

Shoot

Live
Trap

Shoot

Survey for Goat
Immigration

Monitor Goat Populations

Yes

51

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National Park, 600 E. Park Ave. Port Angeles, WA. 72pp.
Anonymous. 1987b. The Greater Yellowstone Ecosystem: An aggregation of National Park

and National Forest Management Plans, multiple sections.
Anonymous. 1987c. Northern Rocky Mountain Wolf Recovery Plan. USDI, U.S. Fish and

Wildlife Service. 119pp.
Anonymous. 1988. Management Policy: U.S. Department of the Interior, National Park

Service, multiple chapters.
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goats, Sheep Mountain-Gladstone Ridge, Colorado. Bienn. Symp. North. Wild Sheep and

Goat Counc. 2:465-479.
. and . 1982. Population dynamics of mountain goats in the Sawatch

Range, Colorado. J. Wildl. Manage. 46:1003-1009.
. and . 1983. Winter forages of mountain goats in central Colorado.

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Colorado Stud., Ser. Earth Sci., 6:1-59.
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Mt. Goat Symp. Kalispell, Mt. British Columbia Ministry of Rec. and Conser. 243pp.
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of bighorn sheep. M.S. Thesis, Univ. of Montana, Missoula. 245pp.
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52

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. 1977. Ecology of the Rocky Mountain goat in Glacier National Park and the

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54pp.

. 1983. A Beast the Color of Winter. Sierra Club Books, San Francisco. 208pp.

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Manage. 36:1068-1076.
Cooperrider, A.Y. 1969. Competition for food between mule deer and bighorn sheep on

Rock Creek winter range, Montana. M.S. Thesis, Univ. Montana, Missoula. 85pp.
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diet selection by mountain goats and mountain sheep in Colorado. J. Wildl. Manage.

48:799-806.
Davis, W.B. 1938. Summer activity of mountain sheep on Mt. Washburn, Yellowstone

National Park. J. Mammal. 19:88-94.
DeVoto, B. 1953. The Journals of Lewis and Clark. Houghton Mifflin, Boston. 504pp.
Doane, G.C. 1871. Report on the Yellowstone expedition of 1870. 41st Congress, 3rd

session, Sen. Ex. Doc. No. 51, Washington D.C.
Estes, R.D. 1979. Ecological aspects of bighorn sheep populations in southeastern

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