University of Montana ScholarWorks at University of Montana
Graduate Student Theses, Dissertations, & Professional Papers Graduate School
1976
Ecology of Rocky Mountain goats in the Bitterroot Mountains Montana
Bruce Leonard Smith The University of Montana
Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y
Recommended Citation Smith, Bruce Leonard, "Ecology of Rocky Mountain goats in the Bitterroot Mountains Montana" (1976). Graduate Student Theses, Dissertations, & Professional Papers. 6502. https://scholarworks.umt.edu/etd/6502
This Thesis is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. ECOLOGY OF ROCKY MOUNTAIN GOATS IN
THE BITTERROOT MOUNTAINS, MONTANA
By
Bruce L. Smith
B.S., University of Montana, 1973
Presented in partial fulfillment of the requirements for the degree of
Master of Science
U n iversity o f Montana
1976
Approved by: /J - V. 'X' ' Chairman,^ Board^of Examiners
, G ra^ qîai;e Sc hoo 1 JUN 4 , b / 6
Date UMI Number: EP37303
All rights reserved
INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted.
In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion.
UMT Ois»artaition PuWishing
UMI EP37303 Published by ProQuest LLC (2013). Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code
ProQuest*
ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 4 8 1 0 6 - 1346 Smith, Bruce L., M.S., Winter 197^ Wildlife Biology
Ecology of Rocky Mountain goats in the Bitterroot Mountains, Montana (203 pp.) j Director: Bart W. O'Gara
Mountain goats (Oreamnos americanus), native to a seven-drainage portion of the Bitterroot Mountains in western Montana, were studied between January 1973 and June 1975. Six individual goat herds occupied restricted, traditional, winter ranges in six of the drainages for 7 to 8 months each year and migrated 5 to 1 0 miles ( 8 to 16 km), during June, to summer ranges at high elevations. Seventy-five percent of the population, estimated at 153 goats in 1975, consisted of animals 2 years of age or older. Productivity equalled 40 kids:100 adult females In 1974 and 42:100 in 1975. Censuses indicated higher p ro d u c tivity during 1972 and 1973. Declining natality was attributed to in-utero or neonatal losses precipitated by environmental stress during 2 severe winters and late spring "green-up". The Fred Burr drainage herd, which was intensively studied, declined 25 percent from 1973 to 1975. Natural mortality exceeded hunter harvest with kids suffering higher natural mortality than other age classes. Investigation of habitat use on a microscale disclosed that snow conditions influenced habitat selection and distribution on winter ranges. Socially dominant animals exploited snow-free c liff ledges while subordinates occupied less optimal h a b itat during the c r it ic a l w in ter period. Small group sizes (averaging 1 . 5 animals) during winter and spring reduced intraspecific competition and distributed forage utilization. Environmental temperatures and location of lush forage influenced habitat selection on summer ranges. Wintei—spring home ranges for adult females averaged 1 5 8 acres (64 ha) and somewhat less fo r other age classes. However, goats spent the majority of time in high use areas measuring 17 acres (7 ha) or less. A summer home range of 1,456 acres (589 ha) for an adult female reflected the increased mobility of goats and wide distribution of their biological requirements on summer ranges. Grasses and sedges comprised the bulk of goat diets during all seasons. The importance of various food plants on winter ranges was evaluated on the basis of abundance, preference, and nutritional value. Annual censusing techniques and a reduction in hunting permits were recommended fo r population management. P o ten tial impacts o f land development were discussed.
I I ACKNOWLEDGEMENTS
The Montana Cooperative W ildlife Research Unit (U.S. Fish and
W ild life Service, U niversity o f Montana, Montana Department o f Fish and Game, and W ild life Management In s titu te cooperating) and the
Foundation for Environmental Education provided financial support for
this project.
I am sincerely grateful to Dr. Bart W. O'Gara, my major advisor, for his support and friendship throughout this study and for critical review of the manuscript.
Thanks also to committee members Reuel Janson and Drs. Bob Ream and Lee Metzgar for review of the thesis. Dr. Ream provided telemetry equipment, and Mr. Janson and John Firebaugh, both o f the Montana
Department of Fish and Game, furnished equipment, flight time, and needed advice throughout the study. Kenneth Greer, Montana Department of Fish and Game, provided laboratory assistance and facilities.
Biologists Gary Halvorson of the Lolo National Forest and John
Ormiston of the Bitterroot National Forest supplied equipment and maps
I thank Klaus Lackschewitz of the U niversity of Montana Botany
Department for identification of plants from the study area; Jim
Reichel, Skip Scaggs, and Steve Fairaizl for assistance capturing mountain goats and hauling gear; Terry McCoy for telemetry help; and
Nancy Hill for her part in preparation of the manuscript.
My wife, Connie, contributed in many ways in the field and
I I I during the writing process. Her companionship, suggestions, and understanding are deeply appreciated.
Connie and I both wish to thank Bonnie Evans and Norman
Frankiand. Their warm friendship and encouragement, throughout the study, w ill long be remembered.
F in a lly , I express my thanks to Nan, Nubs, and the rest of the
Fred Burr herd for making this study possible and a rewarding experience.
I V TABLE OF CONTENTS
Page
ABSTRACT...... ii
ACKNOWLEDGEMENTS î î i
LIST OF TABLES...... v îî
LIST OF FIGURES...... x
Chapter
I. INTRODUCTION...... 1
I I , DESCRIPTION OF STUDY AREA...... 5
Location...... 5 Topography and Geology ...... 5 C lim ate ...... 11 V egetation ...... 13 Economy and Land Use...... 16 Agriculture ...... 17 I rrlgatlon ...... 17 M ining...... 18 Timber ...... 19 Roadless and wilderness areas...... 21 R ecreation ...... 22 Trends and Future Outlook ...... 27 Population characteristics...... 27 Agriculture and subdivision...... 30 Timber ...... 31 Recreation ...... 31
I I I . METHODS...... 33
Terms Used ...... 33 Cens us Ing...... 34 Capture, Marking, and Telemetry Techniques.... 36 Movements ...... 37 Habitat Analysis...... 38 Food H ab its...... 47 Hunter Data ...... 49
IV. RESULTS AND DISCUSSION...... 50
Seasonal D is trib u tio n ...... 50 Page
Population Dynamics...... $4 Numbers...... 54 Aerial censuses ...... 59 Estimated herd sizes ...... 63 Population structure ...... 64 Productivity and survivorship...... 65 Natural mortality ...... 70 Hunter harvest ...... 80 Analysis of mortality...... 82 Grouping...... 85 Daily Activities ...... 93 Seasonal activity patterns ...... 94 Temporal feeding and bedding p a tte rn s ...... 9 8 Habitat Use...... 99 E le v a tio n ...... 99 Exposure ...... 102 Slope ...... 1 0 5 Vegetative associations ...... IO8 Terrain types ...... 113 Patterns of habitat use and distribution on the Fred Burr winter range ...... 121 Predicting habitat selection ...... 12? Migrations and Winter Range Fidelity ...... 129 Seasonal Movements ...... 1 34 Seasonal home ranges ...... 1 34 High use areas ...... 143 D aily movements ...... 147 Food Habits and Food A v a i la b il it y...... 1 49 Rumen analyses ...... 1 49 Winter range investigations ...... 1 54 Feeding techniques ...... 16 6 Reproduction ...... 167 M ating...... I 6 7 Kidding...... 169 Appraisal of reproductive success...... 171
V. MANAGEMENT RECOMMENDATIONS...... 17&
Hunter Harvest ...... 178 Census ing...... 1 77 Land Development ...... 1 79
V I. SUMMARY...... 184
REFERENCES CITED...... 186
Appendix
A. HABITAT TYPES...... 194
B. LIST OF UNDERSTORY PLANT SPECIES...... I 9 6
vi LIST OF TABLES
Table Page
1. Slope Inclinations of selected trunk canyons ...... 10
2. Precipitation and snow depth 1960-1975 16 miles (26 km) S-SW of Fred Burr Reservoir in the Bitterroot Mountains...... 12
3. Monthly temperatures and precipitation, Hamilton, Montana, 1935-1964 and 1973-1975 ...... 15
4. Drainage areas o f canyons in study a re a ...... 18
5- Land ownership in R avalli County in acres ...... 20
6. Forest industries in Ravalli and Missoula Counties...... 21
7. Numbers of elk and deer hunters on the Bitterroot Forest 1965-1973 ...... 26
8. Components of population change ...... 28
9. Per capita income ...... 29
10. Population projections 1970-1990 ...... 30
11. R avalli County land tren d s ...... 30
12. Classification of mountain goats...... 33
13. Average group size and observed intergroup distance on summer and winter ranges on the study area ...... 54
14. Estimated size of the Fred Burr goat herd in 1973 ...... 59
1 5 . Herd sizes and composition calculated by cohort- completion from ground censuses of winter ranges during 1 9 7 5 ...... 60
16. Numbers of goats counted on aerial surveys by personnel of Montana Department of Fish and Game during May ...... 62
17- Mountain goat herd stru c tu re during w in te r ...... 65
18. Survivorship and mortality rates of the Fred Burr goat herd ...... 68
V I I Table Page
19* Age, sex, location, and condition of goat remains ...... 7 8
20. Results of mountain goat hunting1955-1974 ...... 8l
21. Location of mountain goat kills in Hunting District 240...... 8 3
22. Diurnal activity budget by month for mountain goats in the Bitterroot Mountains ...... 95
2 3 . Monthly percent use of exposures by mountain goats on transitional and winter and summer ranges ...... 104
24. Monthly percent use of vegetative associations on transitional and winter ranges ...... 1 1 0
2 5 . Monthly percent use of understory types by feeding and bedding groups...... 1 1 2
26. Monthly percent use of vegetative associations oh summer ranges ...... 114
2 7 . Monthly percent use of understory types by feeding and bedding groups...... 1 1 5
2 8 . Monthly percent use of terrain types on summer ranges and on transitional and winter ranges ...... 116
2 9 . Monthly percent use of terrain types by feeding and bedding groups...... 118
3 0 . Distribution - related data for mountain goats on the Fred Burr winter range ...... 123
3 1 . Seasonal home ranges and high use areas for six recognizable goats of the Fred Burr Canyon herd ...... 14l
3 2 . Mountain goat food habits as determined by analysis of nine rumen samples ...... 1 5 0
3 3 . Productivity of important herbaceous forage plants of mountain goats...... 1 5 6
3 4 . Productivity of additional herbaceous forage ...... 157
35- Classification of eight shrub species from five "key areas" on the Fred Burr winter range according to past use...... 1 6 0
VIM Table Page
36. Protein content of winter forage plants in Fred Burr Canyon, Montana, Rattlesnake drainage, Montana, and the Anshola watershed, British Columbia ...... 164
I X LIST OF FIGURES
Figure Page
1. Location of the Bitterroot North Planning Unit ...... 6
2. The seven-drainage Bitterroot study area ...... 7
3. Mean monthly temperatures for a Bitterroot Valley (Montana) station, an adjacent timber!ine cirque, and an alpine peak ...... 14
4. Development status of the Bitterroot North Planning Unit in 1974 ...... 23
5. Development status of the Bitterroot North Planning Unit projected for 1994 ...... 24
6 . Locations of tagged evergreen ceanothus plants on the Fred Burr w in te r range...... 48
7. Distribution of mountain goat winter ranges in the Bitterroot study area ...... 51
8 . Frequency distributions of winter range ground censuses o f Fred Burr Canyon...... 57
9. Frequency distributions by class of goats from total censuses of the Fred Burr winter range ...... 58
10. Trends in a e ria l censuses o f the study area and Hunting District 240...... 61
11. Monthly group size and composition for Fred Burr Canyon...... 87
12. Annual group s ize and composition on the Fred Burr winter range ...... 91
13. Winter and spring daily feeding and bedding peaks in the study area ...... 9 6
14. Monthly mean elevation of goat sightings from 1973 to 1 9 7 5 ...... 101
15. Monthly mean slope used by groups observed from January 1973 to June 1975 ...... 106 Figure Page
16. Monthly distribution of feeding/bedding groups on slopes of transitional and winter ranges...... 107
1 7 . Monthly distribution of feeding/bedding groups on slopes of summer ranges...... 109
1 8 . Linear distribution of goat sightings across the Fred Burr winter range ...... 124
1 9 . The pattern of spring migration from winter ranges to summer ranges pursued by mountain goats in the Bitterroots ...... 1 30
20. Winter-spring home range of Y Sigma during 1975 ...... 136
21. Winter-spring home range of AF Beta for 1975 ...... 137
22. Wi n ter-sp r i ng home range o f AF Alpha fo r 1975 and sequential relocations of her during 1974 ...... 138
2 3 . Wintei—spring home ranges of AF, Nan, fo r 1974 and 1 9 7 5 ...... 139
24. W inter-spring home ranges o f AF, Nubs, fo r 1974 and 1 9 7 5 and of AM, Captain Hook, fo r 1975 ...... 140
2 5 . High use areas for six mountain goats of the Fred Burr herd for 1975 ...... 144
2 6 . High use areas fo r Nubs (N) and Nan (NAN) during 1 9 7 4 ...... 146
2 7 . Locations of five "key areas" on the Fred Burr winter range (A-E) on which numbers of eight browse species were classified according to past use by mountain goats...... 161
XI CHAPTER I
INTRODUCTION
Studies of Rocky Mountain goats (Oreamnos americanus) reveal that
food h ab its, seasonal movements and ranges, population dynamics and other parameters are peculiar to individual goat populations (Brandborg
1955, Chadwick 1973)- To enhance the sporting and e s th e tic values of this species through proper management requires accurate information on each population. From January 1973 to June 1975, I gathered data on
the mountain goats native to the Bitterroot Mountains of southwestern
Montana, with emphasis on winter ecology and population dynamics.
The history of the Bitterroot goat population is sketchy.
Recounting game conditions described by Alexander Ross in 1823 and 1824,
Koch (1941) wrote "Passing on up the Bitterroot Valley, elk, deer, and mountain goats were very numerous..." When the Valley was settled in
the la te l 8 0 0 ‘s, mountain goats were reportedly common along the west-
side c l i f f s (Anon. 1963). In 1905, the Montana Fish and Game Department established state-wide hunting regulations restricting the hunter to one either-sex mountain goat per year. Through 1947, portions of the
Bitterroot Mountains remained open to goat hunting more consistently
than other areas of the State. Seasons varied from 9 to 90 days in
length. From 1919 through 1942, annual estimates of big game numbers
by the U.S. Forest Service provided the only records of mountain goat numbers. Estimates for the Bitterroot National Forest fluctuated
1 2 greatly during that time, from 3 7 9 goats to a peak of 1 , 3 8 8 in 1 9 2 6 ,
Casebeer et al. (1950) attributed the wide variations to inconsistent censusing by changing personnel rather than dramatic fluctuations in numbers o f goats. In 1943, the Fish and Game Department began estim ating big game numbers fo r each management unit in Montana.
Annual estim ates for the B itte rro o t Unit averaged 670 goats from 1943 to 1946, In 1946, the Wildlife Restoration Division of the Fish and
Game Department initiated a long-term study of mountain goats.
Objectives were to gather data on l) life history and food habits of a
small population and, 2 ) sizes of populations and distribution of goats
state-wide. During September 1947 of that study, aerial surveys were made into 17 of the B itte rro o t canyons and 111 goats were counted. The
investigators estimated the entire Bitterroot population at 310, less
than half the number reported for any of the previous 2 0 years.
Casebeer et al. (1950) reported on the Bitterroot herd as follows:
" I t is evident now that the base herd has not been as large in recent
years as reported. It was not high enough to support the annual kill of 45 to 5 0 goats which were known to be taken each year from 1944
through 1947. A winter loss can be expected in any mountain goat herd.
With the added burden o f a large hunter take, such as that in the
Bitterroot, injury to the herd does occur. The Bitterroot herd has
been on the decrease and a relief from the hunting pressure should help
restore former numbers."
The hunting season was subsequently closed in the B itte rro o t un til
1955 when hunting began on a limited permit basis. This system of 3 harvesting mountain goats continued to the present with the exception o f an unlim ited season in 1966. A erial surveys o f the B itte rro o t Unit
(now divided into Hunting Districts 240 and 250) were flown during May
1948, 1 9 5 0 , 1 9 5 4 , 1 9 5 5 , 1 9 5 7 , and 1974 to determine population trends
(See Aerial censuses). Survey results were expressed in "air minutes over goat range per animal seen" to provide relative densities
(Anon, 1 9 6 3 ).
The B itte rro o t Range in Montana occupies an area roughly 10 miles
( 1 6 km) wide and 40 miles (64 km) north to south along the Montana-Idaho border. A series of glacial canyons originating along the Bitterroot
Divide drain the east flank of the Range and empty into the Bitterroot
River. The upper portions o f those canyons lie w ithin the Selway-
Bitterroot Wilderness Area, while the lower portions are Bitterroot
National Forest land. Brandborg (1955) described fall migrations of goats from summer ranges to winter ranges in the Bitterroots of Montana.
He stated that goats, which were d is trib u te d in the upper canyons at elevations up to 9,000 feet (2,743 m) during September, spent the winter on the lower south exposures at elevations of 4,000 (1,219 m) to 6,000 feet (1,829 m). He added that this appeared to be a complete movement from high elevations and north aspects.
Since 1891, lumbering has been an important industry in the
Bitterroot Valley. By the end of World War II, old-growth stands on accessible private and State lands on the Valley bottom and foothills were nearly depleted. Since then, the industry has become increasingly dependent upon timber from National Forest lands. Furthermore, the
Valley's population increased 17 percent during the 1960's, and the 4 current annual growth rate approaches 6 percent (Anon. 1974c). Many newcomers and long-time residents seek to maintain the high-quality rural living and recreational opportunities the Valley and surrounding mountains provide. Increased demands upon the Bitterroot National
Forest for resource development and recreational use may conflict with the needs of mountain goats wintering in the eastern extremities of the
Bitterroot canyons. Unlike other big game animals, human activities have seldom forced goats from th e ir native ranges. However, along the
Salmon River in Idaho (Brandborg 1955) and the Swan Mountains In
Montana (Chadwick 1973), declines in goat numbers followed mining and logging operations adjacent to goat ranges. These declines were a ttrib u te d to improved hunter access compounded by strong attachment of goats to tra d itio n a l ranges. Because the B itte rro o t goats have not been studied intensively, I initiated this study to collect basic inform ation concerning the population to promote wise management.
Specific objectives were to:
1) investigate population dynamics;
2 ) determine whether mountain goats return to the
same winter ranges each year;
3 ) id e n tify m igration routes between seasonal
ranges; and
4) determine types of habitat used seasonally by the
mountain goat population. CHAPTER 1 I
DESCRIPTION OF THE STUDY AREA
Locat ion
The Bitterroot Range is located along the eastern border of the
Idaho batholith, a relatively high, steep-sided granitic mass occupying most of central Idaho. From the West Fork of the Bitterroot River and
Nez Perce Pass, the Range trends nearly due north to Lolo Creek. The
Range is bordered on the east by the broad Bitterroot Valley and on the west by the Bitterroot Divide. The study area lies centrally in the
Range and encompasses the canyons from Big to Blodgett creeks between
46^31'N and A6^ l 6 'N la titu d e , and 1l4^12'W and 11A^28'W longitude
(Figs. 1 and 2),
Topography and Geology
The B itte rro o t Mountains ris e nearly 6,000 feet (1,829 m) above the floor of the Bitterroot Valley, The high point along the
Bitterroot Divide is Bass Peak at 8,840 feet (2,694 m); however, east of the Crestline, 46 peaks exceed 9,000 feet (2,743 m) including St,
Mary Peak, 9,351 feet (2,850 m), and the Heavenly Twins, 9,282 and
9,243 feet (2,829 and 2,817 m), in the study area. The Mountains are characterized by a series of narrow, serrated ridges extending east from the Divide to an abrupt "front". Between the ridges, 20 major streams flow through deep, steep-walled canyons. The western portions BITTERROOT NATIONAL FOREST
MUSOU
BITTERROOT NORTH PLANNING UNIT
Stevensï
IMDA IMXL-AR IL-DERMCSS
Al_MON MONTANA Map area
20 30 MILES _u _J Fig. 2. The seven-drainage Bitterroot study area
Study area boundary
— B itterro o t Forest boundary
— Wilderness boundary
T ra ils iïiu » ' - pc
■ : 1 1 ' _ ;
ï \ „ \ ' r l : ■ r F f '
V? . % m
I
■ç feiTTERFSO iDia n : IM » L A 8 of the canyons display U-shaped glacial profiles which narrow toward the mouths. Numerous hanging valleys and glacial cirques (many of which contain lakes) occur in lateral tributaries and below the head walls of trunk canyons.
The principal rock of the Bitterroot Mountains is a faintly gneissic quartz monozonite composed of quartz, orthoclase, oligoclase, and b io t it e ; muscovite is sometimes present (Ross 1950:147-148). The light-gray granitoid rock is course-grained to porphyritic. A region of Border-Zone gneiss, 2-3 miles (3,2-4, 8 km) wide, follows the eastern fla n k o f the B itte rro o t Range. Lindgren (1904:21) described the gneiss as a "...light-gray, granular and schistose rock..." having the same primary components as g ra n ite . A second type, a dark-gray gneiss which
is rich in black mica and weathers to reddish outcrops, occurs near
St. Mary Peak (Langton 1935:32-33).
Lindgren (1904:115) summarized the early geological history in the region of the Idaho batholith as follows:
"The geological history of this region probably
begins with the deposition of pre-Cambrian sediments on a
basement of gneiss. Much later, in early Mesozoic time,
sediments, accompanied by basic lavas, were laid down on
the western side of the area described. Granitic intrusions
followed or accompanied a great uplift of these sediments,
and an active erosion reduced the surface to moderate relief.
All this is believed to have been accomplished before the
beginning of the Cenozoic era. A second uplift raised this
reduced topography to the present level of the great 9
Clearwater Plateau, which probably extended far Into
Montana."
The origin of the Bitterroot front is in dispute. Lindgren
(1904:26-27) felt the Border Zone gneisses were older than the intrusive granite and were formed by diastrophic pressures associated with a normal fa u lt along the east fro n t o f the B itte rro o t Range. He considered the fault scarp responsible for the even 18 to 2 6 degree upward slope of the front. Ross (1950:172) more recently postulated the origin of the Border-Zone gneiss was a slab of metasedimentary rocks o f the B elt s e rie s . Doming, associated w ith the emplacement of the Idaho b a th o lith , according to Ross, metamorphosed and raised the slab to its present height.
Until Pleistocene time, running water was probably the major gradational agent sculpturing the B itte rro o t Range. A rectangular stream pattern of trunk canyons joined at right angles by lateral tributaries resulted from the perpendicular alignment of two intei— secting Joint systems in the bedrock (Beaty 1962). High terraces of fluvial-deposited materials fringing the Bitterroot front witness the effect of stream erosion (McMurtrey et al. 1959).
During the Iowan, lllinoian, and Wisconsin stages of Pleistocene glaciation, the Range was covered by a continuous ice sheet from which glacier tongues extended into each trunk canyon (Lindgren 1904:54-55,
Alden 1953:98-103). Glaciers deposited terminal moraines a mile beyond the mouths o f Bear, Fred Burr, M i l l , and Blodgett canyons. The g la c ie rs in Big, Sweathouse, and Sheafman canyons did not extend into the Valley. Beaty (1962) discussed the integral role stream alignment 10
played in glacial erosion of the Bitterroot canyons:
"Equally important, as a probable result of unequal
exposure to the sun of north- and south-facing slopes,
an asymmetrical development of tributary and headwater
branches gave the drainage basins their present form, in
which the more vigorous growth o f the secondary canyons
heading on north-facing slopes is apparent. In almost all
of the major stream systems, hanging valleys and cirques
are more common on north-facing slopes, while only on the
uppermost facets of the south-facing slopes are such
features found, and then relatively rarely.
...Another probable effect of the more intensive
gradational alteration of north-facing slopes has been
the creation of asymmetric interfluvial ridges on which
the divide lies south of the medial position."
As a result, the south-facing canyon walls are steeper than the north- facing walls (Table l) and characterized by debris chutes or couloirs and vertical or neai—vertical outcrops skirted by talus cones.
Table 1. Slope inclinations of selected trunk canyons, from Beaty 1962
Dra i nage North-Facing Wall South-Facing Wall
Bear Creek 17° 2 3 0
Fred Burr Creek 2 2 0 2 7 0
M ill Creek 2 1 0 2 7 0
Blodgett Creek 1 8 0 2 5 0 11
C li mate
Northern Pacific air masses dominate the weather of the Bitterroot
Mountains, Moisture-laden air rising over the Bitterroot Divide dumps
8 0 plus inches ( 2 0 0 cm) of precipitation - primarily as snow - along high ridges of the Range, while the Bitterroot Valley receives a scant
13 inches (33 cm) o f p re c ip ita tio n annually (Anon, 1973b), Occasional winter blizzards, accompanied by subzero temperatures, may develop when a r c tic a ir masses sweep southward from Canada, During the w inter of
1 9 7 2 - 7 3 , normal temperatures and subnormal snowfall resulted in a favorable winter for mountain goats. Temperatures during the winters o f 1 9 7 3 - 7 4 and 1 9 7 4 - 7 5 averaged near normal but deep snow accumulated in the canyons (Table 2 ), Prolonged cold, cloudy weather during the latter spring retarded snowmelt.
Summers in the Mountains are typically cool and dry, A rainy period, during May and June, in conjunction w ith snowmelt provides abundant moisture for plant growth. Daytime high temperatures average about 6 5 degrees F (l 8 ^ C) from July through September, but considerable variation occurs with aspect and elevation. Permanent snow remains in cirques on north and east exposures, and tarns frequently remain frozen into July.
Falls may be long and mild, as in 1974, but snow exceeding 2.5 fe e t ( 7 6 cm) f e l l on 31 October and 1 November 1973, and ensuing snows in November and December ushered in a "hard" winter. Arno (1970) reported that timberline alpine larch (Larix ly a llii) stands receive an average annual precipitation of 40 to 45 inches (102-114 cm) with snowpack depths reaching an average maximum of 10 feet (3 m), usually in April, Table 2 . Precipitation and snow depth 1960-1975 16 miles (26 km) S-SW of the Fred Burr Reservoir in the Bitterroot Mountains.
USDA Soil Conservation Service Bozeman, Montana
Sec. 32 T 05N R 23W Snow course: Twin Lakes, Montana Latitude ^ 6^ 09 * Station No. 14C08 P Basin: Columbia Longitude 114° 30* Elevation 6,510 ft. (1,984 m) River: Bitterroot
Precipitation in Inches Water Year Oct. Nov. Dec. Jan. Feb. Mar. Apr. May June July Aug. Sept. Total
1968- 6.10 6.22 9.46 16.21 8.56 6.37 5.92 3.45 4.64 1.21 1 .30 4.48 73.92 1972 Average
1973 1,61 3.54 11.49 7.00 2.94 4.68 2.74 2.63 3.95 1.88 0.57 4.69 47.72 1974 5.10 9.58 11.84 15.85 10.48 8.66 7.47 3.76 4.72 3.92 1.97 1.56 84.91 1975 0.69 4,89 9.58 17.97 7.93 6.84 6.08 2.82 4.51 2.29 5.85 1.11 70.56
Snow Depth in Inches Year Jan. Feb . Mar. Apr. May June
i960- 112 64 1972 * 65 77 109 109
1973 56 78 80 72 25 1974 79 - 136 141 133 108 1975 64 117 128 131 105
^January data collected 1968 - 7 2, February data in 1968 , and June data 1965 - 72. 13
The only measured climatic data from within the study area were
c o llecte d by Arno on St. Mary Peak and in McCalla Lakes Basin. As
Illustrated In Fig. 3, Arno found average monthly temperatures atop
St, Mary Peak and at McCalla Lake 17 degrees and 14 degrees F (8,3 and
10^ C) cooler, respectively, than at Stevensvi11e, Montana, throughout
the year. Thus, the annual average lapse rate is about 3 degrees F
(1.7° C) per 1,000 feet (305 m) elevation (Arno 1970), Weather data
for Hamilton, Montana, appear in Table 3. A Soil Conservation Service
collecting station 16 miles (26 km) S-SW of Fred Burr Reservoir,
provides data on monthly precipitation and snow depth for a location
1 mile (1,6 km) east of the Bitterroot Divide (Table 2).
Vegetat i on
The east-west alignment o f trunk canyons creates abruptly
differing climates on opposite canyon walls. Local flora reflects
those climatic differences. The lower south-facing slopes support
montane associations of ponderosa pine (Pinus ponderosa) and Douglas-fir
(Pseudotsuga menziesii) with a predominately shrub-bunchgrass understory.
At higher elevations, subalpine fir (Abies lasiocarpa), alpine
larch, and whltebark pine (Plnus albicaul is) grow. On north slopes,
Douglas-fir, grand fir (Ab i es grand is), and lodgepole pine (Pi nus
contorta) occur at lower elevations with alpine fir, alpine larch, and whltebark pine dominating above 6,000 fe e t (1,829 m), Engelmann spruce
(Picea engelmanni) is locally common on north exposures at all elevations and on moist sites on upper south exposures. Aspen (Populus
tremu1o i des) grows on montane and lower subalpine talus slopes. West Fig. 3- Mean monthly temperatures for a Bitterroot Valley (Montana) station, an adjacent tim berline cirque, and an alpine peak. From Arno (1970). 70'F 70
50 50
30
20 20 20
J FMAMJ JASOND J FMAMJ JASOND JFMAMJJASOND
Stevensville, Montana McCalla Lake St. M ary Peak 3370 ft 11027m) 0.5 mi (0.8 km) S. of Bitterroot Mtns. mean ann. temp. 45 F St, M ary Pk. 9351 ft (2850 m) 8020 ft (2444m) mean ann. temp, 28°F mean ann. temp. OI F Table 3* Monthly temperatures and precipitation, Hamilton, Montana, 1935-1964 and 1973-1975.
U.S. Department of Commerce Latitude 46^ 15'N National Oceanic and Atmospheric Admin. Longitude ll4 ° 09'W Environmental Data Service Elevation 3,529 ft. (1,076 m) Montana Climatological Data Station: Hamilton, Montana
Monthly Mean Temperatures and Precipitation
Temperature In Degrees F. Annual Year Jan. Feb. Mar. Apr. Hay June July Aug. Sept. Oct. Nov. Dec. Mean
1935- 1964 24.1 29.9 36.6 46.4 54.2 60.1 67.9 65.9 57.6 47.2 34.2 28.7 46.1
1973 24.5 30.6 38.3 42.4 53.1 60.2 66.9 67.3 56.2 46.9 31.9 31.8 45.9 1974 21.3 36.9 37.4 46.2 49.2 64.3 66.1 62.9 55.4 45.9 37.0 31.0 46.1 1975 27.5 25.4 35.0 39.6 50.1 57.3 61.9 62.6 56.1 46.7
Precipitation In Inches
Year Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec. Annual Total
1935- 1964 0.90 0.90 0.64 0.81 1.67 2.04 0.82 0.68 1.05 0.97 1.16 1.10 12.74
1973 0.43 0.17 0.80 0.42 0.67 1.94 0.14 0.55 1.99 1.26 2.69 1.03 12.09 1974 3.51 0.40 1.88 0.30 1.35 1.24 1.01 2.34 0.32 0.48 0.53 0.28 13.64 1975 1.75 1.03 0.74 2.28 1.84 1.34 0.79 3.07 0.63 3.73 16 and east exposures in the study area, limited to upper canyons and higher elevations, lie within the subalpine zone.
The cool, moist creek bottoms support aspen, black cottonwood
(Populus trichocarpa) , ponderosa pine, Douglas-fir, grand fir, western larch (Larix occidental is), subalpine fir, Engelmann spruce, and western red cedar (Thuj a piicata).
Lackschewitz (1970) reported that alpine vegetation is found on p r a c tic a lly a ll the mountain summits exceeding 9 , 0 0 0 fe e t ( 2 , 7 ^ 3 m) elevation since no permanently snow-covered peaks occur in the Range.
He added that the absolute tre e lin e flu ctu ate s to the extent of t 300 fe e t (91 m) rather frequently and has developed at higher elevations on south and west slopes than north and east exposures. Alpine vegetation, subtended by krummholz b e lts , occurs in the study area on the following peaks: Castle Crag, Sky Pilot, Gash, Ranger, St. Mary, and the Heavenly Twins. Lackschewitz (1970) thoroughly described alpine and timberline flora in the Bitterroot Mountains.
Economy and Land Use
The study area comprises roughly the southern half of the
Bitterroot North Planning Unit (BNPU) and the adjacent portion of the
Selway-Bitterroot Wilderness Area (Fig. 1). These lands are administered by the Stevensville Ranger District of the Bitterroot
National Forest. The BNPU extends southward from Lolo to Hamilton,
Montana, and includes 56,485 acres ( 2 2 , 8 6 8 ha) of Forest Service land west of U.S. Highway 93, excluding the c la s s ifie d Wilderness. The natural resources of the surrounding mountains play important roles in 17 the economy of the Bitterroot Valley. Since the Valley's socio-economic status is homogeneous, and since d e ta ile d information is not available specifically for the study area, a discussion of land use and economy for the Bitterroot Valley follows.
Ravalli County comprises 90 percent of the Bitterroot Valley, which is enclosed by mountains except at its junction with the
Missoula Valley on the north. Of the 1,525,760 acres (617,717 ha) of land in Ravalli County, 73 percent is federally owned, 25 percent p riv a te ly owned, w ith the remainder in State or County ownership
(Anon. 1974a). Generally, the private lands are located in the
Valley bottom and along the low terraces, while public lands are on the high terraces and mountains.
Agriculture. Historically, agriculture provided a major source of income in the Bitterroot Valley and currently is responsible for nearly 20 percent of the dollar volume in the local economy.
Principal crops are livestock forage, sugar beets, potatoes, small g ra in s, and f r u i t (Anon. 1974a). In a d d itio n , most farms have dairy or beef cattle. Market disadvantages, resulting from transportation difficulties to distant markets, created a decline in truck crop production and an increase in beef cattle ranching. In 1971, livestock sales grossed 9 million dollars of all agricultural business compared with 1.8 million for crops (Anon. 1973b).
Irrigation. Agriculture in the Valley depends heavily upon irrigation water from the mountains. According to the Montana State 18
Engineer (Anon. 1958:30) about 104,000 acres (42,105 ha) are irrig a te d
in the Valley; 74,000 acres (29,980 ha) of which are supplied by
tributaries of the Bitterroot River. Peak stream flow occurs in May
and June as a re s u lt o f snowmelt and spring rains. By la te summer,
irrigation water is often in short supply. To create more uniform
stream discharge, 27 high mountain lakes were dammed on the Bitterroot
Forest, 6 within the study area. In 1946, Fred Burr Reservoir, with a
water storage capacity of 515 acre feet (635,242 m^), was constructed
by private interests (Norman Frankland pers. comm.). Big Creek is
the largest drainage system in the study area (Table 4).
Table 4. Drainage areas of canyons in study area from McMurtrey et a l. 1972.
2 2 Canyon Drainage Area mi (km )
Blodgett 26.4 (68.4)
M ill 1 7 . 6 (45.6)
Fred Burr 18.4 (4 7 . 7 )
Bear 26.8 ( 6 9 . 4 )
Sweathouse 10.2 (26.4)
B ig 3 2 . 9 (8 5 . 2 )
Mining. The history of mining on the study area dates back to
1 8 7 1 , when a silver vein was discovered near Sweathouse Creek (now known as Pleasant View District) west of Victor. Incomplete records 19
show th a t $6 , 1 7 5 worth o f ore was shipped from 1914 to 1939 from some
of the original claims (Shahinen 1957).
In 1 8 8 7 , mining operations commenced at the Curlew Mine near the
mouth o f Big Creek Canyon. Records show sporadic mining on the Curlew
District. Silver, lead, copper, gold, and zinc ore valued at $541,743
was shipped between 1923 and 1929 (Shahinen 1957)* Over $100,000 worth
of ore was extracted by open pit mining in 1 9 6 7 and 19 6 8 (unverified
records, Bitterroot North Plan). Mining operations continue to the
present, but data on remaining ore reserves are lacking. Other claims
are scattered around the study area but significant mining does not
e x is t (Anon. 1974c).
Timber. Timber production is the major land use in Ravalli
County. Excluding classified Wilderness, forest land represents about
73 percent of the total acreage. Of this land, 95 percent is classified
as commercial forest land (Table 5). The U.S. Forest Service administers
88 percent of a ll fo re s t lands (Anon. 1973b). Ponderosa pine, lodgepole
pine, western larch, Douglas-fir, subalpine fir, and Engelmann spruce
are commercially important species.
In Ravalli County, the timber industry accounts for half of all
manufacturing gross dollars (15% of total earnings) and 2/3 of the
manufacturing employment (10% of a ll wage earners) (Johnson 1972).
Darby is the principal wood processing town. However, roughly 20
percent of all Bitterroot Forest timber is milled or processed in
Missoula County (Wilma Finlayson pers. comm.). Wood products Table 5* Land ownership in Ravalli County in acres from Anon. 1973b.
Land Forest Land Total Owner Owner Wi Iderness Non-forest Non-commercial Commercial Forest Land Total
U.S. Forest Service 281,152 32,027 46,937 749,468 796,405 1,109.584
U.S. Fish and W ildlife Service 2,669 2,669
State of Montana - 8,046 - 22,799 22,799 30,845
Private - Industrial - - 585 21,398 21,983 21,983
Private - Other - 296,272 1,722 62,685 64,407 360,679
Totals 281,152 339,014 49,244 856,350 905,594 1,525,760
N) o 21
industries in Ravalli and Missoula counties appear in Table 6.
Table 6. Forest industries in Ravalli and Missoula Counties from Anon. 1973b.
Type Rava11i M issoula
Sawmi11s 4 10
P1ywood and Veneer Mills - 1
Pulp and Paper - 1
P a rti c le Board - 1
Post and Pole 3 -
Logging Contractors 11 2 7
Tota Is 18 4o
By 1 9 7 4 , approximately 5,000 acres (2,024 ha) within the BNPU were
logged. Nine hundred fifty-nine acres ( 3 8 8 ha) or 1.7 percent of the entire Unit was clearcut. An additional 2,000 acres ( 8 IO ha) which
li e adjacent to logging roads near M i l l , Sheafman, Gash, and Sweeney
creeks were s e le c tiv e ly logged in and p rio r to the 1950's (Anon. 1974c)
Roadless and wilderness areas. The 1.2 million acre (485,830 ha)
Selway-Bitterroot Wilderness Area was created in 19&3* Approximately
10 percent of that Wilderness lies adjacent to the BNPU in Montana.
Lower B lodgett and Fred Burr canyons were excluded from Wilderness classification because of a proposed water storage project in Blodgett 22
and an existing dam, reservoir, and low standard road in Fred Burr
Canyon. Presently, 81,5 percent of the BNPU is roadless and undeveloped
(Fig. 4); 13 5 percent of this is not inventoried roadless (5,000 acres
(2,024 ha) in size and/or 2 miles (3.2 km) between roads). The
remaining 18.5 percent of the Unit contains roads approximately 80
miles (129 km), the majority of which were constructed for timber
harvesting. Fifty-nine miles (95 km) of trails (located primarily in
canyon bottoms) in the BNPU provide access to the Wilderness trail
system (Anon. 1974c).
The M u ltip le Use Plan for the BNPU was revised in 1974 (Anon.
1974c). The resulting Bitterroot North Plan (BNP) is a document
designed to direct long-term land and resource management based on
existing natural resources, land capabilities, and public demands. The
Plan zones the BNPU into 12 management subunits possessing distinctive
land potentials and suitabilities, and presents four management
alternatives and a selected alternative. Implementation of the selected
alternative will reduce roadless areas by 12,030 acres (4,8/0 ha) or 26
percent (Fig. 5) and open another 8,093 acres (3,277 ha) for timber
harvesting by advanced logging systems not requiring roads.
Recreation. Recreation is a leading use of the study area and is
important to the local economy. Scenery and outdoor recreational opportunities provided by the Bitterroot Valley and surrounding mountains
constitute a major drawing card for tourists and many of the people migrating to the Valley. Solitude provided by the Bitterroot Mountains has enhanced dispersed activities such as hiking, backpacking, camping, Fig. 4. Development status of the Bitterroot North Planning Unit in 1974. K BITTERROOT RANGE NORTH LEGEND
Development Status
R o a d l o s * m
Road a d Forest Boundary W i Iderness Boundd ry
PyrsrtiUJ
^St.Jbtaoh . I HaaSft Ooata initttia*
îj-.»‘ - "»»n«rc
t JfüORTWL
— ’ _ —
f CoiHwarfi
» Viinuck I i j r i y g .««!«•» t"
W t ” Fîg. 5. Development status o f the B itte rro o t North Planning Unit projected for 1 9 9 ^. ■tTTCttOOT RANfiE NORTH
S# let Ted Alf*rnative
•toa d !•
Florenc* PROJECTED 1994
.NORTH:
B|-r-TEF?ROOT C
W I U D E R rsi E S S 25 ski touring, horseback riding, mountain climbing, and nature study.
All trunk streams and several lakes within the study area support
populations of fish. Brook (Salvelinus fontinalis), rainbow (Sa 1 mo ga i rdneri), dolly varden (Salvelinus malma) , and native cutthroat
trout (Salmo clarki) are readily caught in summer and fall. Ruffed
(Bonasa umbel lu s ). Blue (Pendragapus obscurus) , and Franklin grouse
(Canachites canadensis) provide upland small game hunting.
Big game hunting fo r e lk (Cervus canadensis) , w h ite -ta ile d
(Odocoileus virginianus) and mule deer (Odocoileus hemionus) , black
bear (Ursus americanus), moose (Alces a lces), mountain lion (Peli s
concolor) , and mountain goat is the principal fall recreational
activity on the study area. The number of deer and elk hunters
steadily has increased on the Bitterroot Forest in recent years
(Table 7)- Bison (Bison bison) and timber wolves (Canis lupus)
formerly inhabited the area and between 1924 and 1926 the last
grizzlies (Ursus arctos) were reportedly killed between Fred Burr and
Bear canyons (Anon. 1971b:6). U nverified reports of g r iz z lie s in
recent years, include a sighting during the summer o f 1974 above
Bass Lake (Mrs. Prescott Hackett pers. comm.).
Since 1955, mountain goat hunting was conducted on a limited
permit basis. Permits were Issued to applicants by virtue of a drawing.
Out-of-state hunters received 10 percent of the special permits. From
1955 to 1 9 7 4 , the annual number of permits issued for Hunting District
240 varied from 15 to 100 (excluding the I 9 6 6 unlimited season); 26
Table 7. Numbers of e lk and deer hunters on the Bitterroot Forest 1 9 6 5 - 1 9 7 3 from Anon. 1974d.
Number of Hunters
Year Dee r Elk
1965 12,084 12,575
1966 1 2 , 6 6 3 14,663
1967 16,344 1 9 , 8 3 8
1968 17,953 21 ,804
1969 1 7 , 2 5 5 18,679
1970 20,304 21,679
1971 1 8 , 1 2 6 20,041
1972 1 9 , 3 0 2 1 9 , 8 3 4
1973 2 2 , 4 5 0 22,646 27 number of hunters averaged 72; hunter success averaged 51 percent; and to ta l harvest averaged 37 goats (Anon. 1963, 1971a, 1973a, 1974d).
The study area is less than an hour's drive from Missoula and communities in the Bitterroot Valley and receives considerable use from local residents. In addition, proximity to two National Parks and several other Wilderness and Primitive areas, and, increasing leisure time and mobility of people in distant metropolitan centers brings many visitors to the Valley. Area motels, restaurants, and retail businesses benefit from recreation.
Trends and Future Outlook
Population characteristics. Ravalli County experienced a population "boom" during the past 15 years. As Table 8 illustrates, the 16.8 percent population increase during the 1960's is attributed primarily to immigration. The 1973 figures indicate the County's population increased another 17.2 percent since 1970 (Anon. 1974b).
Economic and employment data do not show surging employment opportunities as the primary growth stimulant. In fact, high unemployment ra te s , ranging from 6 to 9 .5 percent annually, are a major reason for per capita and median family incomes lagging behind s ta te and national averages. In 1970, per capita income fo r the County ranked 36 percent below the State average and 44 percent below the national average. In that same year, the median family income was
$7,137 with 14.9 percent of all families below poverty level
(Anon. 1973b). 28
Table 8. Components of population change from Anon, 1973c.
Area
Rava11i County Montana
Populat ion
I960 12,341 674,767
1970 14,409 694,409
Change
Number 2,068 19.642
Percent 16.8 2.9
Components o f Change
In 10 Years
BÎ rths 2.052 143,812
Deaths 1 ,611 66,017
Net Migration
Number 1 .627 -58,153
Percent 13.2 -8 .6 2 9
Table 9. Per capita ! ncome from Anon. 1973b.
Area 1 9 5 0 1 9 5 9 1965 1 9 6 6 1 9 6 7 1 9 6 8 1 9 7 0
Rava11i $1,119 1 , 4 7 0 1 ,702 1 ,621 1 , 7 9 0 1 ,941 2 . 1 9 2 County
Montana 1 ,622 2,010 2,455 2,662 2 , 7 6 5 2,942 3.444
Nation 1 , 4 9 6 2 . 2 1 5 2,765 2 , 9 8 0 3.161 3.425 3.933
The 4 5 + age group accounted for the largest population gain in
R avalli County in recent years. By 1970, the County boasted the highest percentage (14.9) of people in the 6 5 + category in western
Montana (Anon. 1973b). The increasing 45 and o ld er bracket resulted from an influx of retired and semi-retired persons.
The a ttra c tio n o f rural liv in g has created changes in the
population distribution pattern during recent years. While incorporated
communities generally grew slowly, adjacent areas were subdivided and
settled rapidly. From 1950 to 1970, rural farm populations decreased
from 44.2 to 19-3 percent, while rural non-farm populations increased
from 3 5 . 3 to 8 0 . 7 percent in R avalli County (Anon. 1974a).
The R avalli County Planning Board (Anon. 1974a) recently projected
population growth fo r the County using symptomatic in d ic ato rs , and
survival and migration information. Projections include high, middle,
and low fig u res fo r the County as well as estimates fo r the three
largest communities (Table 10). The I 9 8 O figure for Hamilton assumes
the eventual annexation of the urban residential area east of the city. 30
Note that similar growth rates for the incorporated communities do not accompany the projected 20 year increases ranging from 48 to 107 percent for the County.
Table 10. Population projections 1970-1990 from Anon. 1974a.
1970 1975 1980 1 9 8 5 1 9 9 0
Raval1i County
High 14,409 17,600 21,400 2 5 , 4 5 0 2 9 . 7 7 5
M i dd 1 e 14,409 17,200 19,350 21,800 24,200
Low 14,409 16,450 1 7 . 9 0 0 1 9 . 6 0 0 2 1 , 3 5 0
Ham i 1 ton 2,499 2,580 5.200 5 . 9 5 0 6 , 4 7 5
Stevensv i 11e 829 860 910 9 4 5 9 8 0
Darby 538 570 550 5 0 0 460
Agriculture and subdivision. From 1964 to 1 9 6 9 , the proport ion of County land in farms declined from 24.1 to 19 . 5 percent This trend is continuing (Tablell).
Table 11. Rava11i County land trends from Anon. 1974a.
Acres 1969 1973 Percent Change
Al1 Agricultural Land 249,227 242,345 -2 .8
Suburban Tracts 6, 575 19.239 188 31
Since 1964, the average value of farm acreage has nearly doubled because of competition for land for residential and recreational uses.
However, current inflated land prices far exceed the repayment price derived from agricultural production. As a result, land subdivision is skyrocketing. A study of land development in Montana by the
Environmental Inform ation Center (Anon. 1975) reveals that the acreage subdivided annually in Ravalli County increased from 9*3 acres
(3 .8 ha) in 1965 to 5,4 6 0 .8 acres (2,211 ha) in 1973 and 8 ,0 0 8 ,9 acres
(3,243 ha) during the f i r s t 6 months of 1974. R avalli County ranks second in the State in total subdivided acreage - 50,267.2 acres
(20,351 ha) as of 1 July 1974. If the present trend persists, the a g ric u ltu ra l base and economic influence of a g ric u ltu re in the County will surely decline.
Timber. Harvesting and milling of timber will continue to play a major role in the County's economy. As harvestable timber stands in the Valley and foothills continue to dwindle, logging activities on the mountain slopes will increase. During the next 20 to 30 years, approximately 20,100 acres (8,138 ha) will be logged; 12,030 (4,870 ha) o f that to ta l by conventional means (Anon. 1974c).
Recreation. Recreational use of public lands is growing annually. This should favorably affect the retail trade business, which is already the largest economic a c tiv ity in R avalli County, but w ill crowd e x is tin g campgrounds and t r a i l s , and diminish back-country solitude. Fish and w ildlife populations will probably decline as more 32 and more fishermen and hunters take to the woods, and as residential and recreational developments of stream frontage and winter game areas conflict with animal populations and reduce their habitat. CHAPTER I I I
METHODS
Terms Used
Mountain goats were classified by age and sex (Table 12),
Table 12. Classification of mountain goats. New born kids were first observed on 28 May during 1973, 1974, and 1975. On this date each year, all goats were classified as 1 year older.
Class Age Abbrev i at ion
kid 0-12 mo. K ye arlin g 12-24 Y 2-yeai—old male 24-36 2M 2-year-old female 24-36 2F ad u It male 36+ AM adult female 36+ AF
"Sighting" and "group" were used interchangeably to denote either
a single goat or several interacting in close proximity to one another
for a period of time.
"Goat-observations" was used to differentiate cumulative numbers of goats seen in an area from the total number inhabiting that area.
"Herd" referred to the total number of mountain goats wintering
in a particular canyon.
"Population" included all goats in a specified number of herds.
33 34
Census î ng
I censused the mountain goat population in the study area from
1 January 1973 to 10 June 1975. Upon i n i t i a l observation, habitat c h a ra c te ris tic s , general behavior, and age and sex composition of each group were recorded on a data form. Only one record per day was made
for each group. Notes on behavior and physical characteristics of goats plus reobservations were entered in a daily log.
Mountain goats were censused on both w in te r and summer ranges.
During fa ll, winter, and spring, I spotted and observed goats from
t r a i ls In each o f the canyon bottoms. Sweathouse Canyon was censused
from the north-facing ridge top. Modes of winter travel included
hiking, snowshoeing, or skiing depending upon snow conditions. An
A rc tic Cat Lynx 11 snowmobile, belonging to the Region 2 Headquarters of the Montana Department of Fish and Game, provided transportation in
Fred Burr Canyon during the winter of 1974-75.
During summer, when goats moved to higher e le v a tio n s , census
routes were the lateral ridgetops between the canyons and the Bitterroot
Divide. Four to 6-day backpack trips along the ridgetops proved slow work due to the rugged, trailess terrain.
Backpack trips were made across winter range in Fred Burr Canyon during la te May and e a rly June 1975 to ascertain reproductive success and post-natal survival of goats. On 10 June 1975, a similar investi gation was made o f Sweathouse Canyon.
At all times of year, I generally observed goats from distances of 200 to 1,600 yards (183 to 1,463 m) using 7x26 mm binoculars and a 35
15” 60x variable spotting scope. All goats sighted during each census were sexed according to horn curvature and basal circumference, as described by Brandborg (1955), and other sexually dimorphic characters such as beard and pantaloon development, and ro stral width. These characters were not sexually distinguishable until 2 years of age, thus the sex of kids and yearlings were recorded only if urinary postures were seen.
Mountain goats were aged by horn length (Brandborg 1955) in combination with rostral length. As Chadwick (1973) suggested, distinctive horn lengths can be detected in 2-year-olds as well as kids and yearlings. A character I found equally reliable for aging goats through 2 years of age was the rostral length. Horn and rostral lengths of animals aged 3-years and older were neither consistent nor distin g u is h a b le in the f ie ld . Goats 3 years o f age and older were classified as adults unless horn annuli could be counted. Separate classification of 2-yeai—olds was important in understanding herd reproductive rates since mountain goats do not achieve sexual maturity until 2.5 years of age (Brandborg 1955).
In ad d itio n to ground censusing during May 1974, and March and
May 1975, aerial surveys in fixed-wing aircraft provided population counts in the study area. These counts were compared w ith previous surveys by personnel o f the Montana Department o f Fish and Game.
I developed a method to calculate herd sizes which I called the "cohort completion" to ta l count method. Goats observed on censuses were categorized in one of six sex and/or age cohorts - K, Y, 2M, 36
2F, AF, and AM. To calculate herd size, I totaled the largest count obtained for each of the six cohorts during all censuses of a canyon.
Because movements between canyons did not occur in w in te r, herd estimates were based exclusively on winter censuses. Like a total count, the more times a herd was censused, the greater the chances of counting every animal in each cohort. This method has a tendency to be conservative.
Capture, Marking, and Telemetry Techniques
To document d a ily and seasonal movements of in d iv id u als, I attempted to capture and mark mountain goats. During November 1973, a base camp (an 8 ft., 2.4 m, pick-up camper) was established 0.5 miles (0.8 km) east of the Fred Burr Reservoir; and 5-pound (2.3 kg) blocks of salt (NaCl 99%, inert matter 1%) were placed at two locations on the south-facing cliffs of Fred Burr Canyon approximately 1,000 fe e t ( 3 0 5 m) above the Creek bottom. Two clover traps were hauled up the mountain side and assembled near the licks. In May 1974, the traps were positioned and anchored over the licks and trapping efforts continued through June 1974.
As a back-up technique, from February through April 1974, I attempted to capture goats with immobilizing drugs on the winter range.
Goats were stalked and shot from 30 yards (27 m) or less with a 2cc d art containing a measured dosage (3-4 mg) of M-99 (Etropine) using a
Cap-chur gun. On occasion, persons stationed at vantage points in the canyon bottom guided me by walkie-talkies toward goats. 37
Immobilized animals were measured, examined for external maladies and parasites, and marked. One AF was marked with a rope-flagging
collar (Craighead et al, 1969). An AM and AF were equipped with AVM
radio transmitters (150 MHz frequency) secured in acrylic collars
(Ream et al. 1971). Colored Mystic waterproof tape, wrapped around
the base of each horn, further identified immobilized animals. Goats were intramuscularly injected with 400,000 units of Penicillin and
Dihydrostreptomycin (2cc Combiotic) to prevent infection and appropriate
dosages o f M 50-50 to revive the animal.
I located marked goats v is u a lly on ground censuses and by radio
telemetry from aircraft. Radio locations were obtained from a Cessna
182 airplane equipped with a double whip antenna system. An AVM
receiver was used. Attempts to locate radio-equipped goats on winter
range by ground triangulation were thwarted by signal bounce between
canyon w a l1s .
In addition to marked goats, recognizable individuals also
furnished data on home range, seasonal and d a ily movements, and
behavior. Unique or deformed horns provided long term identification of goats in the Fred Burr herd during all or part of the study.
Shedding patterns distinguished some animals for short periods of time during spring and early summer.
Movements
Movements, seasonal home ranges, and high use areas for individual goats were determined from ground observations and telemetry fixes.
Relocations were plotted on topographic maps and outlying points were 38 connected to delineate seasonal ranges. Areas of resulting minimum polygons were measured with a polar planimeter (Craighead et al. 1973)*
Clusters of relocations within seasonal ranges designated high use areas. Approximately 75 percent of relocations from a seasonal range were used to establish each known animal's high use area(s) within that range.
Habitat Analysis
Throughout the study, each sighting was plotted on USGS 7*5 minute topographic maps, and elevation and general topographic location were recorded on data sheets. This information was essential for delineating distribution of mountain goats within their range but provided little insight into habitat preference.
Answering the following questions required examination of features of goat habitat and recording them for each group on a microsea le.
1) What specific areas within their seasonal ranges do
mountain goats seek out for their daily activities?
2) What characteristics of these sites are they
selecting for?
Elevation was recorded to the nearest 40 foot (12 m) countour interval and direction of slope, or exposure, was determined for an area within a 15 yard (13.7 m) radius of each group.
Steepness of slope was recorded in degrees from horizontal for each sighting. The angle of slope was derived by calculating its tangent from a right triangle visually superimposed on a 4 inchrl mile 39
(10.2 cm:1.6 km) topographic map. A 200 foot (61 m) interval of e le v atio n co n stitu ted the tr ia n g le 's v e rtic a l leg, and the measured distance across the interval formed its horizontal leg. The triangle was positioned with the observed goat at the midpoint of the vertical
leg. The vertical distance must equal 200 feet (61 m) or more to allow convenient measurement of the horizontal leg in steep terrain, unless topographic maps larger in scale than 4 inchil mile
(10.2 cm:1.6 km) were available. This precluded examination of slope on a scale comparable to elevation and exposure. Less involved methods of slope determination proved too subjective or lacked uniformity.
Sources of error in ocular estimates of slope angle were:
1) observational distance from the slope;
2) angle at which the slope was perceived; and
3) topographic nature of the slope.
These errors were confirmed by comparing ocular estimates with slope angles calculated by the method described above. Ocular estimation of slope angle in typical goat h a b itat embodied the problem o f deciding the vertical distance over which to measure the slope. Since ledges frequented by mountain goats were generally less than 45 degrees in slope, a small vertical distance, say 5 to 15 feet (1.5“4.5 m), produced slope values generally less than 45 degrees. In broken terrain, even moderate vertical distances of 25 to 50 feet (8-15 m) were difficult to visualize and estimation of slope angle became guesswork unless broad categories of slope were used. Thus, calculation of slope angle via the tangent function constituted a consistent, non-subjective method serviceable in goat habitat. 4o
Schemes designed to classify habitat in previous studies of
mountain goats combined terrain and vegetattonal features into four to
eight broad habitat types. Such broad divisions of topographic,
edaphic, and vegetational characteristics precluded precise measure
ments o f those h a b itat components mountain goats were s electin g .
Instead, I classified separately the proximate terrain and vegetative
type of each sighting. Many hours of observing goats and considerable
modification of the original system engendered the version used from
July 1 9 7 4 to June 1975.
The vegetational scheme was a two component scheme (understory
and overstory) p a ra lle lin g that developed by Daubenmire and Daubenmire
( 1 9 6 8 ) and modified by Pfister et al. (1972). However, existing
plant cover, regardless of successional stage, constituted vegetative
associations. The vegetative associations and representative species of each are listed in Appendices A and B. Use of this scheme entails
identification of the understory type and dominant overstory within a
15 yard (13.7 m) radius of a given point (a mountain goat).
The understory types are:
01) Water is any flowing or standing body of water.
0 2 ) Bare rock is any unvegetated parent material such as
talus or cliff.
0 3 ) Snowfield is a classification only used from May
through October when snow does not dominate the
terrain used by goats.
04) Alpine tundra occurs only on those peaks noted on page 16. 41
05) Bunchgrass comprises most o f the w in te r range
of goats, occurring in association w ith ponderosa
pine and Douglas-fir on south-facing slopes
generally below 6 , 8 0 0 fe e t ( 2 , 0 7 3 m) elevation.
06) Grouse whort1eberry-woodrush occurs on open ridges
and dry slopes above 7,000 fe e t (2,134 m) on a ll
exposures, in association with alpine larch,
subalpine fir, and whitebark pine.
07) Beargrass-herb is found at moderately high
elevations, 6,600 feet to 8,800 feet (2,012-2,682 m),
on dry to mesic slopes, under Douglas-fir, subalpine
fir, alpine larch, and whitebark pine.
08) Deciduous shrub grows principally on talus slopes,
couloirs, and avalanche tracks at low elevations on
all exposures, but ranging up to 6,500 feet
( 1 , 9 8 1 m) on south-facing slopes. Overstory is
absent or consists of ponderosa pine, Douglas-fir,
and lodgepole pine.
0 9 ) Ericaceous shrub is widespread beneath lodgepole
pine, Douglas-fir, grand fir, subalpine fir, and
Englemann spruce canopy on cool, moist slopes.
This type comprises much of the understory on north
and east exposures between 5,000 and 8,000 feet
(1,524-2,438 m). 42
10) Scattered herb occurs at all elevations and aspects
on summer and w in ter ranges. Its name properly
implies a low density vegetative association of
grasses, sedges, and forbs “pocketed" in areas
with very limited soil development. Such sites
include narrow c liff ledges and cracks in outcrops
which retain adequate water for plant growth.
Overstory is sparse. Representative species on
summer and winter ranges are listed separately
(Appendix B).
11) Heath-herb mat is common on summer range on a ll
aspects in open or parkland situations. It is
particularly common in cirques on drier sites
between 7,500 and 8,500 feet (2,286-2,591 m)
elevation. Dominant species in this association
are Phy1lodoce empetriformis and Carex spp.
12) Senecio-sedqe occurs locally on moist sites at the
base of cliffs or along intermittent streams in
couloirs between 5,500 and 7,000 feet (1,676-2,134 m)
on winter range. This type is more common, however,
on summer range at the head of cirques near melting
snowdrifts, along snowmelt water courses, and on
hydric ledges. Overstory species range from
Douglas-fir to whitebark pine. 43
13) Moist herbaceous mat prevails below snowfields and
other gently sloping, irrigated sites in cirque
basins above 7,000 feet (2,134 m). These are
alpine 1arch/suba1pine fir parklands.
14) Creek bottom is a general category encompassing the
vegetation along all the trunk streams, a type of
very minor importance to goats.
Terrain types describe the predominant geomorphic feature within a 15 yard (13.7 m) radius of a mountain goat. Ten terrain types were
I dent ified:
01) Cliffs without prominent ledges are bedrock slopes
exceeding 45° and generally greater than 60°. Steep
outcrops, fins, and nearly vertical walls characterize
this type. Soil development and plant growth are
restricted to fragmentary ledges and cracks.
02) Cliffs with prominent ledges are slopes exceeding
30° with much exposed bedrock. The general
configuration consists of alternate steep pitches
and conspicuous, gently sloping ledges. Most soil
development and plant growth is limited to the
1 edges.
03) Slide rock is rock debris ranging from 6-inch
(15 cm) talus to large boulders accumulated below
cliffs and along fractured ridges. Due to the
granitic nature of the bedrock, scree does not 44
occur on the study area. Plant growth is
commonly sparse to nonexistent; however, talus
sometimes sustains shrub fie ld s at low elevations
and herbaceous growth in soil pockets at high
elevations. Slopes do not exceed 60^.
04) Couloi rs are debris chutes or avalanche chutes
found on all exposures but most prevalent on south
exposures between outcrops and fins. Most
couloirs accommodate intermittent stream flow,
at least during snowmelt periods. Couloirs
contain variable soil development ranging from
shallow soils supporting shrubs and scattered
trees to exposed bedrock and talus.
0 5 ) Broken rock is rugged, fractured bedrock created
along the tops of many lateral ridges and fins,
particularly on south exposures. Spines, poised
boulders, and abrupt changes in local r e lie f
depict the profile of broken rock terrain. Poor
soil development and spotty plant growth
characterize this terrain type.
0 6 ) Glacially eroded bedrock slopes are smooth,
undulating slopes of light gray granite not
exceeding 40^ inclination. This type is limited
to summer goat range and prevails in cirques. 45
Pocketed soil în depressions and on gentle slopes
often sustains lush seasonal flora.
0 7 ) Parkland colluvial slopes encompass any slope of
4 5 ° or less supporting open forests and associated
understory vegetation. Uniform soil cover and
absence of ledges typify this terrain type.
0 8 ) Forested colluvial slopes are parkland colluvial
slopes w ith dense fo rests.
0 9 ) Cirque bottoms (deep mantle) are flo o rs of hanging
valleys (mainly north exposures in the study area)
characterized by gentle slopes, deep soil, and
heavy fo re s t and ericaceous shrub cover.
1 0 ) Stream bottoms are areas along the floors of all
trunk canyons. Stream bottom is a catch-all
term including all terrain between cliffs and
slid ero ck c o n s titu tin g the lower canyon w a lls .
Forests, interrupted by slide rock and riparian
meadows, predominate.
This dual habitat evaluation system was used to determine the influences of terrain and vegetation on habitat preference, and determine which might better predict habitat utilization by mountain goats. Direct observations of goats and ground inspection of each terrain type and vegetative association for bedsites and evidence of feeding provided information on the importance of each type and association to mountain goats in the study area. 4 6
During November 1974, biomass o f herbaceous vegetation was sampled on w in te r range in Fred Burr Canyon, using the Ranked-Set
Method (H alls and Dell I 9 6 6 ). Current annual growth of 14 highly utilized plant species was clipped from 137 9-6 feet^ (0.9 m^) plots and weighed in the field with a spring scale. Ocular weight estimates were made for additional species. For most species field weights were converted to oven-dry weights. The sampled area was a
PP/DF/Bunchgrass vegetative association north of Fred Burr Reservoir.
To avoid gross undersampling of narrow ledges, each transect sample point was used i f two and one h a lf o f the three rectangular plots could be correctly arranged on the ground. Thus, half of any one plot could dangle over a drop-off or contain a rock wall. A rough estim ate o f forage biomass per acre (ha) was derived.
Condition and r e la tiv e abundance o f browse plants on fiv e key areas of winter range were investigated. Numbers of eight species of shrubs were recorded along belt transects. Past utilization, by mountain goats, of all available leaders was assessed. Browsing of
0 to 33 percent of available leaders received a low use rating;
3 4 to 6 7 percent rated moderate; and 68 to 100 percent rated high.
To test nutritional value of plants eaten by mountain goats, crude protein content of 9 shrubs, 1 grass, 1 sedge, 1 coniferous tree, mosses, and lichens were analyzed. Connie Isdahl and myself collected plant material between 14 and 30 March 1975 from key winter range in
Fred Burr Canyon. Shrub leaders, blades of grass, etc . were collected in a random fashion from plants. Current annual growth from all Fig. 6. Locations of tagged evergreen ceanothus plants (general vicinity of letters A and B) on the Fred Burr winter range. The cliffy area north of Fred Burr Reservoir, delineated by a dotted perimeter, was sampled fo r herbaceous forage production. The heavy north-south dotted lin e is the axis from which the lin e a r d is trib u tio n of mountain goats on the Fred Burr w inter range was measured. a f p m
S600 'S*-QO- 5000 Frtd Burr Res
■5000-
680C. SCALE 1.24000
/./ 1000 1000 2000 3000 4000 a 5000 6000 1 kilometer
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL 49
Contents of 9 mountain goat rumens, 8 hunter-killed during fall
1 9 7 4 and 1 wintei—kill collected in May 1974, were examined. Plant material was identified by the author and quantified, as described by Saunders (1955), by employees of the Montana Fish and Game Research
Laboratory at Bozeman, Montana.
Hunter Data
In 1 9 5 9 , the Montana Department of Fish and Game initiated a hunter questionnaire which was mailed each fall to goat hunters.
This information was reviewed. I also devised a questionnaire and mailed it to permit holders in District 240 during the falls of 1973 and 1 9 7 4 .
Examination of hunter-killed goats, in the field and at local taxidermists, supplied data on horn development and age and sex composition of the harvest.
Remains of 12 mountain goats, found during periodic reconnaisance of the study area, provided information on sex and age composition of natural mortality. CHAPTER IV
RESULTS AND DISCUSSION
Seasonal Distribution
Mountain goats in the B itte rro o t Mountains occupy d iffe r e n t summer and w in te r ranges. Each trunk canyon in the study area, except
Sheafman Canyon, supports a number o f animals each w in te r. Those animals occupying winter range in a given drainage are considered a herd, for example, the Fred Burr Canyon herd. From December through
May, goats are restricted to their respective herd winter range and do not travel between drainages.
The eastern 4 miles (6.5 km) of the south-facing canyon wall in each drainage constitutes the winter range (Fig. 7)* Winter ranges are continuous and characterized by steep, broken terrain in which tiered cliffs, skirted by talus, and dissected by debris chutes or couloirs, predominate. Local relief from drainage bottoms to interfluvial ridgetops increases from about 1,000-2,000 feet (305“
610 m) near the canyon mouths to 3,000-4,000 feet (915“1,220 m) at the western end of winter ranges. Exposed bedrock limits most tree and dense understory growth to moderate slopes and ledges where a soil mantle has developed. Only on the Big Creek winter range do large areas of forest grow. Erosive forces of water, snow, wind, and gravity perpetuate early successional stages.
50 Fig. 7- Distribution of mountain goat winter ranges in the B itte rro o t study area. Winter range in each drainage begins near the canyon mouth and extends about 4 miles (6.4 km) west along the south- facing canyon w a ll.
Winter range boundaries J
4 Heavenly fa *T " wins St Mflfy ' ::f I P h Ranger S torm y j / « n P ORTH B8IÉ 1 2?1 3i2
\ A/ü
P iss iPrari
W hii^ Matitl
W 779 »93 i I Sky rv«v-i ,‘f Pilot •
P ufçi huit“ï,uT»
— ■ 2»iO T o te m
^VtJ tlur #/<üf
Sfita/mun u. BrTTFRWOOrfl,# ijift V a WtlOFlOWfR' ' ijiitti H ill
■■ ■■*.:'
nhiiijfit , "eîjbocEjr-^ C^MTON !" . ' i 11 ■ .... V „ ;lLJ^ . • ;
......
. •' I'JIaniiltoii”^ iîU-:-• ■ '* v ' ' ^ Downing " ;:'i 52
Snow depths are a primary determinant of goat distribution in winter. Steep slopes, southerly exposures, and the action of westerly winds afford the eastern south-facing canyon walls with excellent snow-shedding properties. Contrarily, on the western 5"6 miles
(8 - 9 . 5 km) of south-facing canyon walls, and the length of north-facing walls, snow accumulates to depths of 5“15 feet (1.5-4.5 m) in winter and remains Into spring.
In Bear Canyon, w in ter range is divided into two portions. Bear
Creek forks 3 miles (4.8 km) west of the canyon mouth. Goats wintered along the main stream to a point 1 mile (1.6 km) west of the forks where the south-facing canyon wall becomes densely timbered. The main body of the Bear Creek herd wintered along the south aspect of the in te r flu v ia l ridge between Bear Creek and South Fork Bear Creek to roughly 1.4 miles (2.3 km) west of their confluence (Fig. 7). More forage and better ledge development exist along the South Fork.
Goats were never observed during winter ground and aerial censuses o f Sheafman Canyon. S uitab le h ab itat is lim ite d . A small c liff complex 0.7 mile (1 km) long near the canyon mouth offers potential winter habitat but forest and talus dominate the remainder of the south-facing canyon wall. In addition, snow depths are greater in
Sheafman Canyon because the drainage bottom exceeds 6,000 feet (1,830 m) along most of its length, compared to 4,500-5,000 feet (1,370-1,525 m) in the oth er canyons.
Goats began moving onto w in ter ranges in November. From January through May, animals were evenly distributed in small groups over 53 winter ranges between 200 and 2,000 feet (60 and 610 m) above drainage
bottoms. During June, following kidding, mountain goats left their winter ranges and soon reached high interfluvial ridges and the
Bitterroot Divide which constitute summer ranges. Although winter
ranges were casually covered, surveys from July through mid-October
1 9 7 4 disclosed only 1 of 136 goat-observations on winter ranges. Of
the remainder, 132 were above 7,300 feet ( 2 , 2 2 5 m) and 86 percent were
using cirques (primarily north, south, and east aspects), 7 percent
south-facing slopes, 5 percent ridgetops, and 2 percent north-facing
slopes. Cirque basins fulfilled all habitat needs of mountain goats
in summer, including abundant lush forage, water, bedding, and escape
terrain, dusting sites, and varied microclimates to aid in
thermoregulation.
Mountain goats were more dispersed on summer ranges than winter
ranges (Table 13). During winter when deep snow limits food availability, goats were restricted to relatively small areas. In summer, when food and other biological requirements were available over
relatively large expanses of mountainous terrain, mountain goats were
dispersed, as in winter, throughout suitable habitat. Some areas on summer ranges appeared more popular than others, and goats were
repeatedly observed in them. However, high densities of animals did not remain in these areas more than a few hours or a day at a time.
During mid-October, goats began appearing on south-facing canyon walls west of winter ranges. This section of trunk canyons constituted a transitional range utilized for about 1 month. Mountain goats in Fred 54
Burr Canyon spent much of the rut on transitional range in 1974.
Table 13. Average group size and observed intergroup distance on summer (July to 17 October 1974) and winter ranges (January to 27 May 1975) on the study area.
Average Average Distance No, Groups Group Size Between Groups
Summer range 50 2.17 776 yards (710 m)
Winter range 309 1.47 442 yards (4o4 m)
Population Dynamics
Numbers. Mountain goats in the B itte rro o t Mountains occupy different summer and winter ranges. In winter, each investigated canyon (except Sheafman) supported a herd of goats which spent roughly
7 months, mid-November to mid-June, on a restricted area of winter range. Movements between winter ranges did not occur. Therefore, it was feasible to conduct several censuses of a canyon during the w in te r months and combine the maximum counts fo r each age and sex class to calculate herd size. Only counts conducted from January through 27 May were used to establish herd sizes. Members of the Fred
Burr herd displayed perennial fidelity to that winter range (see
Migrations and Winter Range Fidelity). Therefore counts from Fred
Burr Canyon during the 3 winters of the study provided information on productivity, mortality rates, and survivorship. 55
During 155 ground census days over a 2.5 year period, I observed groups of goats 780 times accounting for 1,274 goat-observations.
"Group" and "sighting" are used interchangeably throughout the text to denote either a single goat or several interacting in close proximity to one another for a period of time. These 155 days include only days during which goats were actually seen. Of these totals,
126 census days, 717 groups, and 1,138 goat-observations were on w in ter ranges. Fred Burr Canyon was chosen fo r intensive study of population dynamics as well as aspects of mountain goat winter ecology
In Fred Burr, 594 sightings accounting for 960 goat-observations resulted from 10, 2 7 , and 37 days of ground censusing during the winters of 1973, 1974, and 1975, respectively. Only total censuses, censuses during which a ll of the known w in ter range in a canyon was surveyed, were used to calculate herd sizes. The calculated size of the Fred Burr herd was 29 in 1973, 32 in 1974, and 27 in 1975 based on
7, 9, and 21 to ta l censuses of the w in te r range.
The accuracy of herd counts and age and sex classification undoubtedly improved during the course of the study for several reasons.
1) Progressively, more winter censuses were conducted
from 1973 to 1975.
2) W inter censusing e ffic ie n c y improved w ith the use
of a snowmobile in 1975. More time was spent
scanning and less time spent traveling. 56
3) Sampling proficien cy improved through
familiarization with terrain utilized
by mountain goats and the boundaries of
winter ranges.
Figs. 8 and 9 compare frequency distributions for numbers of
goats observed on to ta l censuses of Fred Burr Canyon. Histograms for
1975 are nearly complete, w h ile the histograms fo r 1973 and 1974 are
discontinuous and show little central tendency. This reflects the
e ffe c t of sample size upon the d is trib u tio n s . In order to compensate
fo r the few censuses made in 1 9 7 3 , a proportionality equation was
used to estimate the Fred Burr herd size. This equation.
mean no. kids mean no. kids per census 1 9 7 5 = per census 1973 maximum no. of X known kids assumes that the mean proportion of goats observed in an age and/or sex class is equal in 1973 and 1975. This assumes that s îg h ta b îlîty
(probability of seeing goats) is equal during the 2 winters. By solving
the equation for each class and summing + %2 + ' * * ^6' ^ total estimated herd of 36 was derived for 1973 (Table 14). This must be considered a conservative estimate as the class means for 1973 are probably low due to lesser sampling proficiency of the observer in
1973. Using this same method to estimate class sizes for 1974, yielded a herd estimate of 28 goats, 4 fewer animals than the observed total of 32. This further suggests that using the 1975 ratios furnishes a conservative estimate of the 1973 herd size. Fig, 8. Frequency d istrib u tio n s of w in ter range ground censuses (January-May) o f Fred Burr Canyon. Only total censuses are shown. 1973
4 Mean = 18.7 3 wi O «A 2 4 6 8 10 12 14 16 18 20 22 24 W) C 0 U 1974 5 4 M e a n = 13.1 3 2 1 n 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
0) .o E 1975 3 z 5 = 13.4 4 M ea n 3 2 1
2 4 6 8 lO 12 14 16 18 20 22
N o . of Goats / Census Fig. 9. Frequency d istrib u tio n s by class of goats from total censuses (January-May) o f the Fred Burr winter range. 2M 2F AM A F Unclass.
6 - m ean= 5.5 1.7 1.2 1.2 1.7 5.8 L7 W 3 4 2J
n n r LI n n 0 2 4 6 1 0 2 4 6 6 0 2 4 6 6 0 2 4 6 8 0 2 4 6 6 0 2 4 6 6 0 2 4 6 6 # 6- # 2.8 1.9 0.9 0.5 3.3 3.3 1.0 # 9 1974 4 # C e V nn tin M 11 h r 0 2 4 6 6 0 2 4 6 6 0 2 4 6 6 0 2 4 6 6 0 2 4 6 8 0 2 4 6 6 0 2 4 6 8
16- 2.4 1.8 0.5 1.1 ’ 2.6 4.5 0.3 14
12
10 1975 e 8 - .# E 6 - 3 z 4 2 li L 1 n 1 0 2 4 6 6 0246601466024680246 802466014 6 6 No. of Goots/Census 59
Table 14. Estimated size of the Fred Burr goat herd in 1973* Estimate deduced using the p ro p o rtio n a lity equation described in te x t
1 9 7 3 1 9 7 4 1975
Total Calculated by
Cohort Completion 2 9 32 2 7
K 9 / 9 . 2 7 / 4 . 6 4 No. Observed/ Y 3 / 4 . 7 6 / 5 . 3 5 No. Calculated 2M 2 /4 .8 2 / 3 . 6 2 w ith 1 9 7 5 Ratio 2F 3 /2 .2 1/ 0 . 9 2 o f Means^ AM 4 / 3 . 3 6 / 6 . 3 5 AF 8/1 1.6 9 /6 .6 9
Estimated Herd 36(+) 28(+) 2 7
^see Fig. 8
Censusing of other drainages in the Bitterroot Mountains in 1973
and 1974, primarily yielded information on mountain goat distribution and
h a b ita t use in those canyons. Herd s ize s , calculated by the cohort"
completion method, based on 1975 winter censuses, appear in Table 15*
Three w in te r censuses in Sheafman Canyon in 1974 and 1975 resulted in no
sightings or sign of goats. Observations from drainages other than Fred
Burr are frequently lumped in the text.
A erial censuses. On 9 May 1974, and 26 May 1975, a e ria l censuses of the
study area and adjacent drainages were flown. The results of these flights
and previous flights by personnel of the Montana Department of Fish and
Game appear in Table 16 and Fig. 10. Comparing the 1948-1957 flig h ts to
those o f 1 9 6 6 - 1 9 7 5 , the average number of goats observed per drainage Herd sizes and composition calculated by cohort-completion from ground censuses of winter ranges during 1975- Also shown Is the composition of the study area goat population during summer 1974, and the estimated size of each herd during winter 1975»
No. Herd Composition No./Percent Total No. All No. Goats Max imum Herd Estimated jge Censuses Censuses Class if led Count Size KY 2M 2F AM AF Herd Size
1 3 10 ii® 11 1/10 1/10 0/0 1/10 5/50 2/20 30 ;e 3 4 22 10 12 1/8.3 1/8.3 1/8.3 0/0 3/25 6/50 14 L 1 2 4 23 13 20 3/15 1/5 1/5 1/5 7/35 7/35 27 Sheafman 2 2 0 0 0 ------Mill 2 2 19 11 14 1/7.1 1/7.1 2/14.3 0/0 5/35.7 5/ 35.7 20 Blodgett 3 3 50 26 27 5/18.5 3/11.1 1/3.7 1/3.7 8 / 29.6 9 / 33.3 35
Total for 11/ 7/ 5/ 3/ 28/ 29 / All Six 11 16 124 71 84 13.3 8.4 6.0 3.6 33.7 34.9 126
Fred Burr '73 6 9 148 23 29 9/31.0 3/10.3 2/6.9 3/10.3 4/ 13.8 8 / 27.6 36 Fred Burr '74 8 23 287 32 32 7/21.9 6/18.8 2/6.3 1/3.1 6/18.8 9 / 28.1 32 Fred Burr '75 21 35 357 21 27 4/14.8 5/18.5 2/7.4 2/7.4 5/18.5 9 / 33.3 27 Fred Burr 20/ 14/ 6/ 6/ 15/ 26/ 1973-1975 35 67 792 76 88 22.7 15.9 6.8 6.8 17.0 29.5 -
Study Area 15/ 12/ 7/ 5/ 33/ 38/ (7 Drainages) 1975 32 51 481 92 111 13.6 10.9 6.4 4.5 30.0 34.5 153
Study Area Data gathered on ground surveys July to mid- 19/ 15/ 1/ 6/ 44/ 47/ Summer 1974 October, 132 goat-observations 14.4 11.4 0.8 4.5 33.3 35.6
^includes 10 classified and one unclassified mountain goats. ON o Fig. 10. Trends in aerial censuses of the study area and Hunting District 240. Average number of goats was calculated by dividing total number of goats observed by total drainages surveyed (exclusive of Sheafman Canyon). Graphs were plotted from data collected by personnel of the Montana Department of Fish and Game and the author.
D is tric t 240
Study area only
1 9 7 5 ^ Exclusive of Big Creek Canyon Av. No. Goats Observed / Drainage
Ui 00
CO
w
Air Min. / Goat Observed 62 declined and air time per goat increased during the latter period in
Hunting District 240. Figures for both categories remained about the same for the study area.
Tab le 16. Numbers of goats counted on a e rial surveys by personnel of the Montana Department of Fish and Game during May.
Dra i nage 1948 1 9 5 0 1 9 5 4 1 9 5 5 1957 1 9 6 6 1 9 6 7 ^ 1 9 7 4 ^ 1 9 7 5 ^
Big 1 1 7 10 12 6 6 0 19 Sweathouse - - 2 6 3 - - 6 2 Bea r 4 3 6 9 3 3 - 6 6 Fred Burr 7 8 5 6 7 4 12 8 9 Sheafman - - - 0 - - 0 0 0 Mi 1 1 1 4 2 6 3 3 1 3 3 B1odgett 18 1 6 8 5 1 13 8 5
^Goats observed by Idaho Department of Fish and Game biologists.
^Survey by the author and John Firebaugh, biologist for Montana Depart ment o f Fish and Game.
^Survey by the author.
In 1 9 7 5 , maximum ground counts of mountain goats exceeded aerial counts in five of six drainages in the study area. In the other (Big
Creek Canyon), 19 goats were spotted from the air compared to 11 observed on the only to ta l ground census of the w in te r range. In the seventh canyon, Sheafman, goats were never observed on aerial surveys.
In 1 9 7 5 , the mean counts from ground censuses In each drainage of
the study area exceeded aerial counts by almost 40 percent. This occurred despite the fa c t that 19 goats in Big Creek is the second 63 highest figure recorded for any canyon in the Bitterroot Range since a e ria l census i ng began in 1948.
Estimated herd s iz e s . A fte r intensive work in Fred Burr Canyon,
1 feel six censuses, and preferably more, are needed for calculating herd size s. Censuses conducted from la te March to ea rly May consistently provided the largest counts. Insufficient numbers of censuses were conducted in all other drainages within the study area.
Thus, herd sizes were estimated from ground and aerial censuses and
indices such as track and pellet group densities on winter ranges.
Other factors taken into consideration were: 1) dates and weather conditions of censuses; 2) visibility of winter ranges from respective drainage trails (trails on the south side of creek bottoms afforded a better view of winter ranges than those on the north side; and 3) nature of winter range (extensive forest in Big Creek Canyon hindered observations). Although derived somewhat less than scientifically, I believe these estimates are near actual herd sizes (Table 15).
My estimates average 22 percent higher than those reported by
Casebeer et a l. (1950). They derived th e ir estimates from 9 hours and
15 minutes of aerial surveys conducted in 17 of the 20 major canyons of the Bitterroot Range during September 19^7. Those surveys yielded
111 observed goats.
Casebeer et al. (1950) termed their estimate of 310 goats in the
Bitterroot Range (265 in Hunting District 24o) “conservative." In 1975,
John Firebaugh (pers. comm.) estimated 250-350 mountain goats in
District 240. My herd estimates total 153 goats for the study area. 6 4
Results of aerial surveys and personal ground reconnaissance of other drainages in District 240 suggest a like number of goats inhabiting drainages outside the study area, or a total population in District
240 of approximately 300.
Population s tru c tu re . Population stru ctu re is based on censuses of winter ranges from January through 27 May. Based on minimum herd sizes calculated by cohort-completion, the percent composition of sex and/or age classes was computed fo r each herd (Table 15)- Of 110 different goats wintering on the study area in 1 9 7 5 » 75 percent were
2 years of age or older. Similarly aged populations were reported on by Anderson (1940) in Washington, Casebeer et al. (1950) in Montana,
Chadwick (1974) in Glacier National Park, and Vaughan (1975) in
Oregon. Brandborg (1955) and Hibbs et al. (1969) investigated populations in Idaho and Colorado in which 2-year-old and adult classes constituted only 51 percent of all animals. Data from 3 years in F red
Burr Canyon indicate that recent declines in natality are responsible for the agedness of the population (Tables 15 and 17)*
Females accounted for 53 percent of the adult population in the study area. Brandborg (1955) in the Selkirk Range and along the Se1way
R iver, Anderson (1940), and Hibbs et a l. (19^9) reported that females comprised 50, 59» 54, and 51 percent o f adult numbers. Chadwick (1973 and 1974) found AF:AM ratios of 67:33 in the Swan Range and 62:38 in
Glacier National Park. The sex ratio for 2-year-olds in the Bitterroots favored males, 59:41, compared w ith 40:60 in G lacier National Park. 65
Table 17- Mountain goat herd structure during winter.^
Number : 100 Adult Females Number Adu 1 t Herd (s ) Cl ass1f 1ed Kid Yearl 1 ng 2-Year-O1d Male
F red Burr 1973 2 9 113 38 63 5 0
F red Burr 1974 31 7 8 6 7 33 67
F red Burr 1975 2 7 44 56 44 56
Remaining drainages In study area 1975 83 38 24 28 97
Study area 1975 110 39 32 32 87
Study area 1974^ 132*^ 40 32 15 94
^7 April is the approximate date of comparison as maximum numbers in each sex and/or age class were observed before or during early April each year.
^Data obtained from ground surveys of summer range from July to October 1974.
^May Include reobservations of the same Individuals.
Productivity and survivorship. From January 1973 to May 1975,
K:AF ratios on winter ranges provided Information on reproductive success
(Table 17). All age classes were concentrated and more easily observed
In large numbers at this time of year than during summer and fall.
During w in te r 1975, 15 Ks and 38 AFs (39 Ks: 100 AFs) were known to
Inhabit the study area. Although they Include 2Fs In the adult class, most In ves tig ato rs report K:AF ra tio s between 50 and 80 per 100. Only
Brandborg (1955) In the Selkirk Mountains during fall 1950 and winter
1 9 5 1 and along the Salmon River from spring 1949 to winter 1950, 66 and Cowan (1944) i n Canadian national parks in 19^3 found ratios comparable to mine.
Data from systematic surveys of summer ranges from July through early October 1974 yielded a K:AF ratio of 40:100. This suggests minimal kid m o rta lity between summer and m id-w inter. Brandborg (1955),
Casebeer et al. (1950), and others concur that most losses, in all age groups, probably occur during winter.
During 3 w inters in Fred Burr Canyon, the number o f kids observed on winter range were 9 in 1973, 7 in 1974, and 4 in 1975, with no evidence of twinning. The respective numbers of AFs were 8, 9, and 9.
However, productivity was probably lower in 1973 than these figures indicate because several adult females were believed unaccounted for
(Table 14). As early as January of that year while maternal bonds were yet strong, 6 of 21 observations of AFs in F red Burr were AFs without young.
Two 6-day surveys across kidding areas in F red Burr Canyon during late May and early June 1975 substantiated low post-partum reproductive success. Only three of seven AFs were observed with offspring each month. On 10 June 1975, fiv e AFs were located in Sweathouse Canyon, only two w ith young. These figures indicate 42 percent p ro d u c tiv ity .
Members of the Fred Burr goat herd displayed perennial fidelity to that winter range (see Migrations and Winter Range Fidelity). Therefore, comparison of herd composition in F red Burr Canyon during 3 winters, as calculated by cohort-completion, provided an evaluation of survival rates. Since the herd size in 1973 was probably an underestimate of 67 one or more age classes, survivorship between w inter 1973 and 1974
appears better than actually occurred. Changes in herd composition
from w in te r 1 974 to 1975 are believed an accurate representation of
survivorship from April to April of those 2 years. Tables 17 and 18
summarize information on survival rates. From 1973 to 1974 and 1974
to 1975, survivorship was 67 and 71 percent for kids; 100 and 67
percent for yearlings; 100 and 63 percent for 2-year-old and older
males; and 91 and 82 percent for 2-yeai—old and older females.
Hunting accounted for several losses in Fred Burr Canyon
during the falls of 1973 and 1974. Four animals, 2 AFs and 2 AMs,
were killed by hunters on fall or winter range in 1973. Assuming
perennial loyalty to winter range, at least one more 2-year or older
female and two 2-year or older males must have comprised the 1 9 7 3
herd than census figures indicated. Three AMs were shot on fall or winter range in F red Burr in 1974, which accounts for all losses in
this group from 1974 to 1975.
Regarding the 197^ and 1975 herd composition in Fred Burr
Canyon, m o rta lity was evenly d is trib u te d among a ll age classes. Adult
males were not exempt from non-hunter m o rta lity during this period,
as one wintei—killed AM was discovered in mid-April 1975. Kids
suffered the greatest natural mortality of any cohort in F red Burr
Canyon. These losses occurred roughly between 10 and 22 months of age
as A p ril was the month in which peak numbers of goats, in a ll classes, were observed. Losses among kids between parturition and 10 months of age remain unknown since surveys during June 1973 and 1974 were not Table 18, Survivorship and mortality rates of the Fred Burr goat herd based upon herd composition in early spring as calculated by cohort-completion.
Class Compos i tion No./Percent Unclas- Herd Per- Herd No. Hunting Natural Total Year K Y 2M 2F AM AF slfied^ Size cent Size Surviving Mortality M ortality M ortality
1973 29 36'
Annual MortalIty -5 17.2
32 32 25 4/11.1 7/19.4 11/30.6
Annual Mortal Ity -8 25.8
1975 27 27 23 3/9.4 6/18.8 9/ 28.1
Two Year Mortal Ity -13 21.7 7/10.3 13/19.1 20/29.4
^Not Included In m ortality calculations. Estimated, see section on Numbers. ^CalculâtIons are based on nine AFs counted on 6 A pril. An AF, tranqui1ized and marked on 10 February 1974, is believed to have died prio r to 6 A pril. The carcass of another AF was discovered on 15 A pril. This AF 00 died less than a week before (snow earlier In the week had not covered her carcass), thus only 8 AFs survived through early spring. ^CalculâtIons are based on five AMs although one died during A pril. 6 9 conducted to obtain post-partum K:AF ratios. However, productivity figures from throughout the study area during summer 197^ were comparable to figures obtained on winter ranges the ensuing winter
(Table 17). This Indicates that K mortality from summer to early spring was negligible. It seems likely that mortality between 10 and 22 months of age occurred p rim a rily during spring on w inter range after goats have endured the ravages of winter for several months.
Brandborg (1955) reported low survival rates of Ks and low productivity following winters characterized by periods of extreme cold with deep and crusted snow. He attributed this to lowered avaliability of foods and use of those of poor nutritional quality. Cowan (1950) blamed severe winter conditions in 19^3 as the cause of poor K survival in
Canadian Parks. Edwards (1956) observed that goat populations had still not recovered in 1953 from declines during harsh winters of the mÎd-1940's. Across the Bitterroot Valley from my study area.
Rideout (1974) found high K and Y survival - 72 and 98 percent - following the mild winter of 1972-73 as compared with 67 and 100 percent in the Bitterroot Mountains that same year. Following the harsh winter of 1971-72, Rideout (1974) found K and V survival of only 27 and 41 percent. Yet, productivity during all 4 years of
Rideout's investigation remained constant at 77“84 Ks/lOO AFs in contrast to my findings in the Bitterroots.
Efforts to determine the cause(s) for declining reproductive rates began during f a l l 1974. Cheatum and Sever i nghaus (1950) found that fertility of white-tailed deer was a direct reflection 70 of nutrition, and that poor quality forage, lack of availability due to snow depths, and long periods of restriction and competition for available food may contribute to lower reproductive success in spring.
Winter range condition, intraspecific competition, and possible causes of failing reproductive success are discussed in the sections on Food
Habits and Food A vailability, Grouping and Reproduction.
Natural mortality. Most of the large predators of North America are probably capable of killing young mountain goats. Guiguet (1951) described an attack by a wolverine (Gulo gulo) on mountain goats in
British Columbia. Wolverines regularly traveled creek bottoms and
lower slopes below goat winter ranges in the Bitterroot canyons.
During May 1974, I surprised a wolverine which was robbing rodent snap-traps 0.25 m ile (0 .4 km) from my camper in Fred Burr Canyon,
On 27 August 1974, two different wolverines were observed in alpine cirques being used by mountain goats. No direct interactions between wolverines and goats were observed.
Black bears inhabit the study area and forage along the south- facing canyon walls in spring and summer. On 21 May 1974, I reinspected the carcass of an adult nanny originally discovered on 15 April at the base of a c liff on the Fred Burr winter range. The carcass had been scavenged by black bears and coyotes (CanÎs 1 atrans). Numerous scats of each, containing goat hair, were in the vicinity. On 15 April, the carcass was fed upon only by coyotes. Black bear predation on mountain goats is not documented but Chadwick (1973) noted black bears neith er harassed nor showed interest in goats in the Swan Mountains. During 71
June 1 9 7 5 , I observed a subadult bear foraging less than 100 yards
( 9 0 m) from a bedded adult billy. Although the bear was clearly visible, the goat paid little attention and continued to doze. Although black bears scavenge goat carcasses In spring, they seem unlikely predators on goats at any time of the year.
Coyote tracks frequently crossed talus slopes and lower cliffs of goat ranges during winter and spring. Sometimes coyote tracks followed those of goats for several hundred yards. During February 1974, a coyote harassed a nanny and kid for several minutes In Fred Burr Canyon,
The coyote repeated 1 y attempted to dissociate the nanny and kid by seemingly challenging the nanny to charge. When obliged, the coyote dashed aside and cut behind the nanny. Nevertheless, she recovered each time to chase the coyote from her kid and eventually routed him.
In addition to the carcass mentioned above, coyotes ravaged the carcass of an 11-year-old billy found above Fred Burr Reservoir on
3 0 A p ril 1 9 7 5 . This carcass lay below an 18 foot (5*5 m) cliff In an area prone to frequent avalanching. The cause of this animal's death was undetermined. It Is believed that coyotes may occasionally take a weak or sick goat in winter while scavenging cliffs for wlntei— k l 11ed anIma1s .
Cowan (19^4), Brandborg (1955), Hoiroyd (19^7), and Hornocker
(1 9 7 0 ) noted cases of mountain lion predation on goats. Jack Wemple
(pers. comm.), a local outfitter, reported an apparent lion kill of an adult nanny In Big Creek Canyon during fall 1974. Lion, bobcat
( Lynx rufus) , and lynx (Lynx canadensis) tracks were Infrequently
at ranges. 72
Golden eagle (Aquî1 a chrysaetos) attacks on mountain goats are well documented in the lit e r a t u r e . Observations of eagles carrying
off kids or knocking goats from cliffs are reported by Anderson (19^0),
Seton (1953), and Brandborg (1955). Gene Smith (pers. comm.), a
resident of the Bitterroot Valley, told me of a probable goat kill by
an eagle in Bass Canyon of the Bitterroot Mountains. During June
1971, while hiking up the Bass Creek trail, he flushed a golden eagle
in a meadow 4 miles (6.4 km) below Bass Lake. Upon investigating, he
discovered a freshly killed kid of the year, still bleeding from
talon punctures. Outfitter Jack Wemple (pers. comm.) witnessed a
golden eagle carrying a kid goat from a ledge in Big Creek Canyon
during June 1970.
Golden eagles reside In the study area much of the year and one
nest was located in 1975* Eagles often circled over goats but were
generally ignored. On two occasions, 1 one eagles swooped low over
bedded goats which leaped to their feet and stared at the birds.
Mountain goats may recognize eagles as adversaries and behave
a g o n is tic a lly toward them. During la te w in ter 1974 along the Lochsa
River In Idaho, Dr. B.W. 0 'Gara (pers. comm.) witnessed a golden
eagle land on a ledge 80 yards (73 m) from a feeding mountain goat.
The goat hesitated briefly, then lowered its head and charged the
bird, putting it to flight.
When evaluating the impact of predatory animals on goat
populations, one must remember that traditional use of their native,
cliffy habitat may have evolved partially through selective pressures 73 created by predation. Mountain goats, successfully transplanted Into
relatively predator-free locations such as the Black Hills, South
Dakota, and the National Bison Range, Montana, are th riv in g in non-typical goat habitat. In their chosen environment, mountain goats are unsurpassed mountaineers. A predator pursuing a mountain goat
risks bodily injury from a fall, avalanche, or retaliation from its
prey. Seton (1953) and Brandborg (1955) described the ability of cornered goats to dispatch attacking dogs (CanIs fami1 laris) . Some
predator losses can be expected in any goat population but probably are less significant than other sources of mortality.
Wood ticks (Dermacentor andersoni) and winter ticks (Dermacentor a 1 bip ictus) are indigenous ectoparasites of the Bitterroots. I found >
dense populations of these parasites present on winter ranges while
they were encountered less frequently at high elevations on summer
range. Clark et al. (1970), investigating dispersal and maintenance of Colorado tick fever In Mill Canyon of the Bitterroot Range, found
highest concentrations of _D. andersoni on c liff ledges at mid-elevations on the south-facing canyon w a ll, preferred h ab itat o f w intering mountain goats. During 3 years of trapping, Clark et al. (1970) found
the percentage of six rodent hosts infested with wood ticks ranged from 16 percent of C1ethrionomys gapperi to 100 percent of Spermoph11 us
1ateralIs» The latter frequents cliff-1edge habitat but the former does not. The emergence of dormant wood ticks in spring appeared synchronized with climatic factors. Adult ticks first appeared during warm, sunny days of la te March 1973 whereas in 1974 and 1975 cold 74 temperatures and snowstorms delayed th e ir emergence u n til mid- to
1 ate A p ri1 .
The winter tick is a one-host parasite of large herbivores.
Larvae appear in late autumn, attach to hosts then or during winter, and remain on th e ir hosts a fte r engorging. Adults that emerge from the nymphal stage become engorged by early spring, about the time that _D. anderson i attach and begin engorging (Gregson 1956).
Ticks may accelerate the commencement of shedding by mountain goats in spring. Most animals began shedding during the th ird week of A p ril 1973 but began a week la te r the follow ing 2 years. Brandborg
(1955) noted that a pinkish discoloration, produced by moistened tick excrement, often stains molting sites. Chadwick (1973) stated that molting sites are targets of intensive comfort activities due to irritation from chafing hair and tick infestations. Goats in the
Bitterroot Mountains scratched, rubbed, horned, licked, and nibbled their coats far more frequently from mid-April through June than during other months. Open sores and bleeding wounds appeared on goats, primarily kids and yearlings at that time. A IQ-month-old kid, which rubbed and scratched its bloody shoulder constantly on 19 A pril 1973» appeared weak and unsteady.
Three adult goats immobilized in Fred Burr Canyon during 1974 were parasitized by ticks. A 4-year-old female was immobilized during
February on the eastern portion of the winter range. More than 100 ticks of both species were removed from a 4 inch (10 cm) square area on her neck. This animal behaved abnormally when initially pursued 75 by traveling downs 1 ope along the creek bottom rather than fleeing to cliffs. She was weak, responded very slowly to injections of M 50-50, and is believed to have died later that winter. A 3-yeai—old female captured on 14 April 0.5 mile (0.8 km) east of Fred Burr Reservoir had numerous ticks of both species lining the borders of a molted area on her shoulder. Her physical condition was good. On a 9-yeai—old male immobilized above Fred Burr Reservoir, only one albipictus was found during 5 minutes of searching. His condition was good. My travels across winter ranges also indicated fewer ticks on the western port ions.
Deer and moose frequently die from loss of blood associated with heavy infestations of 2- alb ip i ctus (Gregson 1956); while domestic rabbits (Oryctolagus spp.) may be practically exsanguinated with as few as 60 to 75 female anderson i feeding over a period of about 12 days
(Jellison and Kohls 1938). Although no evidence exists of mortality in mountain goats directly attributable to ticks, Kerr and Holmes
( 1 9 6 6 ) pointed out that presence of ticks constitutes an added stress and may affect goat survival, particularly following a severe winter.
This would seem the case in the Bitterroot Mountains.
Mortality resulting from accidents is difficult to assess.
Many investigators have observed falls by goats and Seton (1953) witnessed one such fa ta l accident involving 5 goats, a ll of which f e ll from a ledge on which they were stranded. I saw a nanny and kid fall
15 feet (4.6 m) from a narrow 1 edge while attempting to turn around.
The kid landed upright, unharmed, but the nanny crashed back first 76 onto a juniper bush inflicting a wound on her foreleg. In other cases, goats forced subdominants during agonistic encounters off c liff ledges with falls up to 20 vertical feet (6.1 m) resulting in no apparent harm. The F red Burr herd contained 3 goats with broken or deformed horns and several others w ith chipped horn tip s . Goats in other drainages also had broken horns, possibly from falls.
Undoubtedly, winter and spring conditions on steep winter ranges present the g reatest menace. During summer and f a l l , goats negotiated c l i f f s and boulder fie ld s w ith amazing a g il it y and speed. In w in te r, these places were crossed more slowly, often hesitantly, with occasional slipping. Constant thawing and freezing produced unstable snow, icy cliffs, subnivian ice, rock slides, and avalanches. The propensity of goats to feed at snow-free, though often icy or unstable ledge rims, may cause occasional falls. During his study, Brandborg
(1955) discovered nearly h a lf of 25 goat carcasses at bases of c l i f f s .
I twice found goat tracks in snow spotted with blood, possibly resulting from accidental injury.
Snows 1i des occurred from January through May but were larger and more frequent in western portions of the winter ranges. The most perilous areas lay west of winter ranges and were not visited by goats until late spring. Anderson (1940), Brandborg (1955), Hoiroyd (1967),
Casebeer et al. (1950), and Lentfer (1955) described instances of goats apparently k ille d by snows 1Îd es. Chadwick (1973) observed that responses of goats to snows 1 ides and other disturbances depended upon the intensity and fam iliarity of the noise and that young animals 77 generally reacted more vigorously than adults. I likewise observed complete disregard for minor snows 1i des or those occurring at a distance. Nearby, thunderous avalanches often precipitated frantic behavior. In such situations, goats fled headlong across cliffs, or nervously hunkered against rock w a lls , sometimes fo r several minutes after avalanches ceased.
During 1974 and 1975, three carcasses (two mentioned previously) and remains of nine other goats were found on winter ranges. The lo c a tio n , c o n d itio n , age, and sex of these remains are summarized in
Table 19. Remains of 10 goats, aged from horn a n n u li, ranged from
6 to 15 years of age and indicate natural longevity averaging 10.3 years. Three of the 12 remains lay at the bases o f c l i f f s or below snows 1ide areas. Any or all of these animals may have suffered injuries or death from falls or snows 1ides. Remains of four goats were found at traditional bedding grounds; skulls of three, ranging from 9 to 10 years old, were present.
Bones of the 12th animal were found together in the creek bottom of Big Creek Canyon, 500-600 feet (152-183 m) below the nearest goat cliffs. More extreme cases exist in which dead goats were discovered outside th e ir normal h a b ita t. On 26 June 1974, Doug Chadwick and myself investigated the carcass of a 3~yeai—old male discovered several days earlier by a ranger on Cracker Flats, Glacier National
Park. The carcass lay intact, except for the hind legs, in a meadow several hundred yards from the nearest mountain complex and appeared to have been dead fo r about 2 weeks. Rideout (1974) noted the carcass Table 19. Age, sex, location, and condition of goat remains found on winter ranges in the Bitterroot Mountains during 1974 and 1975-
Date Age No. Sex Drainage Locat ion Condi t ion
4/1/74 Fred Burr Canyon Base of 20 ft. Carcass scattered 10 yards (9 m) downs lope AF? winter range (6.1 m) c l i f f with head and most of flesh gone
4/16/74 Fred Burr Canyon Base of 15 ft. Bleached and checked bones (skull with one 13 yrs. winter range (4.6 m) c l i f f horn sheath, pelvis, scapulae, vertebrae) F lying in 4 ft. (1.2 m) diameter area
4/23/74 Big Creek Canyon Gentle slope in Bleached bones (skull with one horn sheath, 15 yrs. creek bottom below pine-fir forest leg bones, scapulae, vertebrae) lying in M winter range 2 f t. (0.6 m) diameter area
4/28/74 Fred Burr Canyon C liff 1 edge and Bleached bones (skull with horn sheaths, 6 yrs. winter range adjacent talus lower Jaw, leg bones, vertebrae) scattered M slope over a 10 ft. (3.0 m) area
4/29/74 Fred Burr Canyon Flat boulder- Spinal column with leg bones, hooves, AF? winter range traditional pelvis and scapulae attached plus some beds i te skin and hai r
5/13/74 Fred Burr Canyon Broad ledge Bleached and badly gnawed humerous Unknown w inter range Unknown
5/21/74 Fred Burr Canyon Upper talus slope One horn sheath in excellent condition oo 11 yrs. w inter range below snows 11 de M area Table 19. Continued
Date Age No. Sex Draî nage LocatIon Conditlon
8 5/21/74 Fred Burr Canyon Upper talus slope Checked and gnawed skull and lower jaw 9 yrs. winter range below snows 1Ide plus one horn sheath M area
9 5/29/74 Fred Burr Canyon Gentle parkland Bleached skull with horn sheaths 8 yrs. winter range colluvlal slope- F tradltlonal bedding area
10 5/29/74 Fred Burr Canyon 45 f t . (13.7 m) Bleached skull with horn sheaths, vertebrae 10 yrs. winter range ups lope from and leg bones M previous entry
11 4/30/75 Fred Burr Canyon 15 f t. (4.6 m) Coyote scavenged carcass (skull with horn 11 yrs. winter range below an 18 ft. sheaths, lumbar vertebrae, pelvis, hind M (5.5 m) cliff legs and hooves plus some hide)
12 7/18/75 Roaring Lion Talus slope Scavenged carcass, skeleton, and most of 10 yrs. Canyon winter hide Intact. Marrow In leg bones dried M range out. 80 of a 6-yeai—old male found in river bottom habitat in the Sapphire
Mountains, cause of death undetermined. During 1975» Nick Grkovic
(pers. comm.), studying movements of elk in Idaho and Montana, discovered the body of a 7“year-o1d female goat melting out of a snow drift near Salmon, Idaho. The carcass was intact, showed no signs of predation, and was located roughly 8 miles (12.9 km) from known goat range. One can only speculate about reasons for these animals dying outside th e ir accustomed h a b ita t. Bone marrow from the animal found near Salmon, Idaho, was red and jelly-like indicating poor health or malnutrition. It is possible that when certain mountain goats become sick or weak, they begin wandering aimlessly downs lope and subsequently die in unusual locales. Malnutrition and physical stress during periods of severe weather and reduced food availability may be contributing factors, as they may to any of the previously discussed forms o f m o rta lity .
Hunter harvest. Hunter kill probably represents the largest single source of goat mortality in the Bitterroot Mountains. Table 20 summarizes harvest information since mountain goat hunting began on a limited basis in 1955. During the past 20 years, hunters killed an average of 37 mountain goats annually, 20 males and 1 7 females, for a hunter success ratio of 51 percent. All age classes, kid through adult, are shot by hunters, although information obtained in 1973 and
197^ from local taxidermists and hunter questionnaires indicates adult animals are taken most o ften . 81
Table 20. Results of mountain goat hunting 1955-1974 based on replies from questionnaires mailed by Montana Department of Fish and Game from Anon. 19&3, 1971a, 1973a, 1974d.
Percent No. No. No. No. No. Hunter Year Permi ts Hunters K ille d Ma 1 es Females Success
1955 15 15 13 0 13 88 1956 3 0 2 9 16 10 6 55 1957 35 35 22 10 12 63 1958 35 35 22 12 10 6 3 1959 4 5 4 5 26 8 18 58 I960 6 0 44 31 15 16 70 1961 100 79 41 17 24 5 2 1 9 6 2 100 83 53 36 17 64 1 9 6 3 100 87 40 24 15 46 1964 100 80 35 2 3 12 44 1 9 6 5 100 100 3 4 21 12 3 4 1 9 6 6 ^ 2 6 9 ^ 2 6 9 105 60 4 5 39 1 9 6 7 75 62 3 6 21 15 58 1 9 6 8 75 65 4 5 21 24 6 9 1 9 6 9 75 62 3 4 18 16 55 1 9 7 0 75 68 44 28 16 6 5 1971 75 65 24 12 12 37 1 9 7 2 75 6 9 35 19 16 51 1 9 7 3 75 66 3 6 12 24 55 1974 75 73 42 2 9 12 58
Totals 1 .589 1 ,4 3 1 7 3 4 3 9 6 335
Averages 79 7 2 37 20 17 51
^Unlimited number o f permits a v a lia b le th is year 82
There are 18 major drainages in Hunting District 240, six of these are in my study area. Since 1955, 60 percent of all hunter kills came from eight drainages, four within the study area (Table 21)
Following the 1973 and 1974 hunting seasons, I mailed questionnaires to mountain goat permittees in District 240. Nonrespondents were contacted by phone when possible. Responses from 62 percent of permit holders in 1973 and 88 percent in 1974 revealed that 78 percent of all mountain goats taken from District 240 during those years were killed
in six drainages, five within the study area, and that those drainages
received a proportionately high percentage of the hunting pressure.
Those six drainages share certain sim ilarities;
1) All contain good trails that are regularly maintained.
2) Road access to t r a i l heads is good.
3) Five of the six drainages have trails providing
access to an adjacent drainage in District 240,
whereas other drainages do not.
Distribution of hunting pressure and consequently goat harvest may be dependent more upon the type and q u a lity of t r a i l systems than actual density of goats. Influencing factors, such as scenic appeal, overall recreational potential, and pattern of use established by word of mouth and tr a d itio n a l use by local guides and o u t f it t e r s , may fu rth e r contribute to the distribution of hunter harvest by drainage.
Analysis of m ortality. Roughly 300 mountain goats inhabited
Hunting District 240 during winter 1975. The number of females in the population potentially capable of producing offspring was about 8 3
Table 21. Location of mountain goat kills in Hunting District 240 based upon responses to questionnaires of the Montana Department of Fish and Game. Figures for 1973 and 1974 were obtained from questionnaires mailed by the author from Anon. 1963, 1967, 1971a.
Total Total Tota 1 Dra1 nage 1955-62 19 6 3 - 6 6 1 9 6 7 - 7 0 1 9 7 3 1 9 7 4 Total
Ca r 1 ton 1 4 0 1 6 S. Fork Lolo 0 0 1 1 One Horse 5 8 0 1 14 Sweeny 11 13 10 1 35 Bass 2 8 3 0 10 1 3 7 2 Kootena i 10 2 8 12 7 6 6 3 Big 12 10 9 7 8 46 Sweathouse 3 5 3 11 Gash 0 0 1 1 Bear 2 1 12 2 4 21 Fred Burr 14 6 16 4 4 44 M ill 9 4 12 1 4 3 0 Blodgett 20 20 19 3 2 64 Canyon 5 3 5 1 1 15 Sawtooth 1 3 1 1 6 Roaring Lion 4 2 3 9 Lost Horse 15 17 8 1 41 Rock 8 7 3 2 20 Tin Cup 13 9 2 2 26 84
39 percent (34.5 percent AFs and 4.5 percent 2Fs) or 117 animals.
K id :a d u lt female ra tio s from summer 1974 and June 1975 (Table 17 and the section on Productivity and Survivorship) indicate productivity rates near 40 percent, or recruitm ent of 47 kids. Annual hunter harvest In District 240 averaged 37 goats since 1955. The same average held during the past 8 years when the number of permits was limited to 75. These data imply that during years when productivity equals 40 percent or less, 3.5 percent or greater natural mortality
(11 or more goats) results in reduction of population size. Class- specific mortality rates over a 2-year period in Fred Burr Canyon show annual losses averaging 21.7 percent. Hunters accounted for half of those losses, 7 goats or 11.7 percent. The 11.7 percent is comparable to hunter harvest District-wide (37 goats killed/a prehunting season population of about 350 goats = 10.6 percent). The remaining 10 percent annual loss rate in Fred Burr Canyon presumably resulted from natural mortality and far exceeds the 3*5 percent maximum which maintains the population.
P ro d u ctivity is not always as low as 40 percent, as censuses during winters 1972-73 and 1973“74 indicate. However, it must average
6 5 percent annually to absorb a 10.6 percent hunter harvest and a 10 percent natural mortality rate. Moreover, the 10 percent figure for annual natural mortality and consequently the 20.6 percent total mortality rate (natural plus hunter), are probably conservative. These mortality rates are derived from herd sizes calculated by cohort- completion as illustrated in Table 18. Arguments, presented in the 8 5 section on Numbers, suggested that the Fred Burr herd was considerably larger in 1973 ” 36 goats - than determined by cohort-completion.
If, indeed, the herd totaled 3 6 during spring 1973» and only 25 of these animals survived to the following spring, then losses equaled 11 goats or 30.6 percent. Hunters killed four members (two AMs, two AFs) of the Fred Burr herd during fall 1973, leaving seven deaths to natural causes or a 19.4 percent natural mortality rate. Natural mortality between spring 1974 and 1 9 7 5 was six goats out of 32 or 18.8 percent.
Over the 2-year period, natural losses were 13 goats (7 + 6) or 1 9 . 1 percent (13 / 36+32) for the Fred Burr herd, almost double the 10 percent rate based on a 1973 herd of 29 animals. Hunter losses totaled seven goats or 10.3 percent (7 / 36+32), the approximate rate calculated above for District 240. Total mortality from 1973 to
1 9 7 5 averages 29.4 percent. Given an early spring population of 300 goats in District 240 and 29.4 percent annual mortality, a 100 percent birth rate among sexually mature females (117) would not offset annual losses (123 goats). Caution must be exercised when extrapolating mortality rates from a single drainage to an entire hunting district. Nonetheless, if natural mortality District-wide approaches either the 10 or 19.1 percent rates demonstrated for Fred
Burr Canyon, i t is probable the goat population in D is tr ic t 240 is d e c lin in g .
Group i ng
Group size and composition varied throughout the year in the study area. Average group s ize was largest during mid-summer and 86 late fall-early winter (Fig. 11). As Brandborg (1955), Casebeer et al.
( 1 9 5 0 ), Hoiroyd (19&7), and others noted, group sizes were smallest in May prior to kidding but increased during summer as nannies, kids, and subadults banded together. During and following the rut in
December and January, groups averaged 2.3 and 2.4 animals. At that tim e, many AMs, which were otherwise s o lita r y , formed mixed groups o f two or more animals with AFs (Fig. 11). From November through January, all but two AMs in groups totaling two or more goats were associated with an AF. The incidence of solitary animals increased rapidly after
January; 70 percent of all AM-observations from February through June were singles. Although no yearlings and only one 2-yeai—old were recorded as singles on summer ranges, individuals from these classes were often solitary during winter and spring. AFs were intolerant of Ys, in particular, on winter ranges.
Small group size and few mixed groups manifested the subsidence of sexual urges and intensified competition for optimum habitat on winter ranges. Group size throughout the study area averaged 1,5 animals from January through May 1973-1975. Eight goats observed on
20 January 1973 was the largest group recorded on winter ranges.
Average observed group size from aerial surveys during May 1974 and
1 9 7 5 was 1.4 goats. Casebeer et al. (1950) reported 1.6 animals per group for 101 goats spotted on an aerial census of the Bitterroot
Canyons during May 1947. Only Hanson (1950) reported comparably small groups for the wintei—spring period. Fig. 11, Monthly group size and composition fo r Fred Burr Canyon, November and December 1973”?^ and January through June 1973-75, and throughout the study area, July through October 1974.
AF groups (groups containing one or more AFs but no AMs) □ AM groups (groups containing one or more AMs but no AFs)
Mixed groups (groups containing at least one AF and one AM)
Subadult groups (groups containing goats 2 years old or younger) -50
N =52
M e a n =2.4
L
M a r
N=10 M ean =1.3
2 4 6 8 2 4 6 8 Nov Dec
G roup Size 88
Chadwick (1973) found a direct relationship between aggression
rates and group size. In particular when two or more 2-yeat—old or older goats composed a group, aggressive tension or interactions rose
and . . often kept groups walking rapidly across areas they would
have fed slowly over in smaller groups." This encouraged a linear
hierarchical composition within groups to achieve group stability.
On winter ranges in the Bitterroot Mountains, small groups appeared
to be selectively adaptive since:
1) The broken nature of winter habitat and dispersed food
favored small foraging groups. Evenly distributed small
groups maximized use of available habitat while reducing
intraspecific competition and the potential for
degradation of small areas.
2) Lower rates o f aggression in small groups promoted
individual conservation of energy under adverse
cond i t i ons.
3) Since predation appeared insignificant, grouping for
mutual protection was unnecessary; grouping would likely
increase the potential for accidents resulting from
crowding on narrow c liff ledges.
Apparently different adaptive social strategies have evolved in other goat populations. Casebeer et al. (1950) reported that goats
in the Red Butte area of Montana ranged in large groups during winter. .
He fe lt this was advantageous in deep snow as the goats developed well-trodden trails between scattered open spots of available feed. 8 9
Chadwick (1973) reported group sizes averaging three to six animals in the Little Creek drainage. There, 8.7 acres (3-5 ha) of windblown ridgetops constituted the primary winter range for 17 mountain goats.
Groups averaging s ix to seven animals in January and February occupied the Mt. Wardle winter range in Kootenay National Park (Hoiroyd 19&7).
DeBock ( 1 9 7 0 ) found th at from January to May, AM groups averaged about three goats, and female-young groups averaged over nine in Kootenay
Park. Group sizes in the Crazy Mountains were larger during late winter, when range was restricted, than in summer or fall
(Lentfer 1955). Saunders (1955) regarded windswept ridgetops and grassy slide-rock slopes as important winter habitat for goats in the
Crazy Mountains. All four of these goat populations occupy winter ranges less broken than those in the B itte rro o t Range. Windblown slopes or ridgetops provide relatively large areas of forage over which groups of five or six goats can easily feed without directly competing with one another. Intragroup agonistic behavior does not jeopardize the lives of group members as it may on steep cliffs.
Such cliffs characterized goat winter ranges along the Salmon River
(Brandborg 1955) and Lemhi Range (Kuck 1973b) o f Idaho and the
Bitterroots where goats formed smaller groups. Brandborg (1955) and
Kuck ( 1 9 7 3 b) reported average group sizes of 3.5 and 2.0, respectively, for those winter ranges. The nature of available habitat apparently dictates winter social strategies.
Winters with deep and persistent snow would further encourage grouping on ranges characterized by windblown slopes and ridgetops as 90 goats become aggregated on less range. Goats In Banff National Park formed large groups during periods of deep snow (Petocz 1973)*
C o n tra rily , such w inters In 1974 and 1975 discouraged grouping in the
Bitterroots (Fig. 12).
On summer ranges, mountain goats in the study area were scarcely more sociable than on w in ter ranges. Small groups dispersed throughout available habitat, while AMs and barren AFs were often solitary. The most significant variation from other months was the inclusion of subadults in adult groups. Only one subadult, a 2F, encountered from
July to mid-October was unaccompanied by an adult. Yearlings often grouped w ith barren AFs. Group s ize on summer ranges in the
Bitterroots averaged 2.17 compared with 3*5 in the Lemhi Range
(Kuck 1973b) and 2.9 along the Salmon River, although Brandborg (1955) considered the average group size for this latter population closer to the 3-5 mean he recorded in the Selkirk Range. These populations, which winter on precipitous cliffs at low elevations, all remained in small groups during summer. Chadwick's (1973) range of three to six animals per group applied yeai—round. However, he added that groups were largest in winter. DeBock (1970) recorded equally large groups on summer and winter ranges. In the Crazy Mountains, groups were larger in winter than summer (Lentfer 1955), and Foss (1962) reported group sizes averaging 2.0 for June, August, and September, and 4.5 for July. For other Montana populations, summer group sizes averaged
2.5 in Glacier National Park (Chadwick 1974), 2.7 along the northern
Continental Divide (Casebeer et al. 1950), and 3-0 in the Sapphire Fig. 12. Annual group size and composition on the Fred Burr winter range, January to 27 May 1973"75- N = 136 goat-observations in 1973, 193 in 1974, and 359 in 1975.
1^1 AF groups (groups containing one or more AFs but no AMs)
I ] AM groups (groups containing one or more AMs but no AFs)
K \N Mixed groups (groups containing at least one AF and one AM)
P'%/1 Subadult groups (groups containing goats 2 years old or younger) m - 171
- 113
-n -9 8
60 — 6 0 “ 60 M ean = 2.2 1.4 1.4
Pet. M ixed Groups = 4.8 2.2 4.8 5 0 - 50 - 50 X Pet. Single w Groups = 47 71 69 C 0> 3 \ o- 40 40- 40
3 0 - 30-
20
[\ \
10
2 4 6 8 10 2 4 6 8 10
G ro u p S iz e 92
Range (Rideout 1974). In all but the Kootenay Park population, mountain goats scattered singly or in small groups throughout available summer range regardless of winter social strategy. An unusual exception was the Red Butte population which formed groups averaging 6.8 animals during July and August. Brandborg (1955) explained, "This was attributable to the greater population density on the Red Butte range and the movement of goats in a circular route over a limited area of nearly 2 square miles." As in the Bitterroot Mountains, vast summer
ranges and c r i t i c a l l y small w in ter ranges are typical of most goat populations. Carrying capacities of winter ranges establish the numerical limits of most populations.
Composition of goat groups, with the exception of kid-nanny pairs, was constantly changing. As reported by Brandborg (1955), Ks remained with their nannies for 10-11 months. The earliest dates on which dissociated Ks were recorded in 1973 and 1974 were 31 and 27 March,
respectively. By late April, Ks were often observed alone, in pairs, or tagging after nannies with Ks. One pair of Ks was observed nine
times in 1975 between 6 April and 25 May. On 17 February 1975, a lone
K, possibly an orphan, was seen in Blodgett Canyon. On the same date,
1 saw an AF accompanied by two Ks. Those were possibly twins or else one was orphaned or separated from its mother. Survival among orphaned or separated Ks is poorly documented in the lite r a tu r e . Brandborg
( 1 9 5 5 ) felt such Ks became vulnerable to starvation and predation.
Rideout (1974) reported that of two Ks separated and recaptured 1 year
la t e r , one was emaciated and the other in good condition. Chadwick 93
(1973) documented o ver-w în ter survival of an orphaned K in the Swan
Range. Not until 4 April in Fred Burr Canyon were other Ks observed w ithout th e ir presumed dams in 1975. The greater proportion of lone
AFs in April and May versus other months attests the dissociation of
Ks from nannies at 10-11 months of age (Fig. 11).
Adult-adult and adu1t-subadu1t groups were somewhat more stable on summer than winter ranges. A radio-equipped AF exhibited an affinity for subadult company. On four ground relocations of that AF between 3 and 17 October, the same two Ys, a female with a broken left horn and a thick, stubby horned male, accompanied her. Previously, on
10 August, two identical Vs followed her. Tracks of the radioed AF
revealed that she migrated to the Fred Burr transitional range with two Ys on 15 or 16 November. On 17 November, she was observed w ith the broken-horned Y. A solitary male Y was also on the transitional
range. A female Y with a conspicuously deformed left horn was spotted alone on Fred Burr winter range several times during winter 1975.
During spring , she formed a cohesive bond w ith the radioed AF, They were first seen together on 2 March 1975» and were together all 11 times I observed the radioed AF during April, May, and early June.
Other lasting ties between adults and subadults were not evident.
Daily Activities
Mountain goats engaged in eight general a c t iv it ie s . Upon f i r s t observing a group, the a c tiv ity engaged in by its members was recorded
The activity pursued by the majority of members in a group was 94 considered as the group's activity. Table 22 and Fig, 13 were constructed from observations made from January 1973 to June 1975"
Seasonal activity patterns. As reported by other investigators, goats devoted most of the d a ylig h t hours to feeding and bedding. These two activities occupied at least 44 percent of all groups observed during each month, and considerably more from January through June
(Table 22 ). Fewer groups were seen tra v e lin g during the c r it ic a l
January through April period than in other months. This supports the idea that goats synchronized daily feeding and bedding activities on the same sites to conserve energy. On winter ranges, goats generally selected beds!tes near the point where feeding bouts ended. In many cases, feeding ceased as goats reached a prime bedding location.
Increased travel during May was associated with AFs moving to kidding grounds. In Fred Burr Canyon, nannies gave birth near the mid-section of the 4 mile (6.4 km) long winter range. Females wintering farther east or west converged on this area in late May. During May and early
June, goats also sought out "green-up" areas and traveled to portions of winter ranges unused earlier in the year due to deep snow. Goats traveled freely between cirque basins on summer ranges, and much fall travel was related to the rut and migration.
Mountain goats spent considerable time standing. Throughout the year, goats interrupted feeding bouts to stand and survey their surroundings. Goats also rose from beds to stare in the d ire c tio n o f a neai—by disturbance. Chadwick (1973) correlated visual ale rtn e ss , or time spent surveying, with age of animal and group size. Solitary Fig. 13* Winter (January-March) and spring (April-June) daily feeding and bedding peaks in the study area. Shown is the percent feeding of all groups of goats observed e ith e r feeding or bedding.
Winter (n = 161 groups)
Spring (n - 390 groups) Sunrise Sunset M ay Feb. Feb. May 100
90-
80-
70- o> c
60-
tf> o. D 50 O O 40- O
30-
20-
lO -
6-8 8-10 10-12 12-14 14-16 16-18 18 20 20 22
Mountain Standard Time 97 adults were most a le r t . As Vaughan (1975) hypothesized, from Ritzman and Benedict's (1931) calculation that domestic sheep (Ovls arles) produced 15 percent more heat while standing than lying down, standing may function to maintain body temperature during winter. In support of this hypothesis, I recorded 15 percent of groups standing during the coldest months, January and February, and none from July through mid-October (Table 22).
Mountain goats spent more time feeding than bedding from January through March; however, a complete reversal transpired In April and continued through June. Heavy snowfall and little melting forced goats to spend more time and effort obtaining sufficient food during winter than spring. By April, warmer temperatures denuded some terrain and, although the exposed forage was of unimproved nutritional value, goats filled their rumens in less time. Percent of groups feeding declined through June p a rtly because Increasing day length provided more hours of light for feeding. Conversely, relatively more groups were bedded
In spring than w in te r. Bedding expends less energy than other activities and would promote conservation of remaining reserves until high quality forage appeared.
Chadwick (1973) and Vaughan (1975) provided w in ter a c tiv ity tables. Their feedingibeddlng ratios were 67:33 and 52:48, respectively, compared w ith 58:42 in the B itte rro o ts . Chadwick (1973) showed a decline In spring feed 1ng:bedd1ng time, 53-5:46.5, less pronounced than in the Bitterroots, 37:63-
Summer and fall data again Indicated feeding as the dominant dally activity. Feed Ing:bedding ratios for summer (July - mid-October) 9 8 and f a ll (November and December) were 58:42 and 73:27, resp ectively.
Both ratios exaggerated actual time spent feeding and bedding during those seasons as goats devoted considerable time to travel and courtship activities.
Temporal feeding and bedding patterns. Fig. 13 illustrates d a ily peaks in feeding and bedding a c tiv ity during w inter and spring.
Ratios of feeding:bedding groups were calculated over 2 hour time intervals to establish the graphs. A midday bedding peak separated minor morning and major evening feeding periods. Goats typically fed ups lope in morning and early afternoon, on winter ranges, and down- slope during evening. Occasionally they returned to their bedsites of the previous night. Morning feeding commenced after 0800 during winter, when winter ranges became illuminated and warmed. During spring, many animals were already feeding before 0800. Poor lighting and fog frequently hampered early morning observations; however, the morning feeding period during spring probably commenced shortly after daybreak. Goats continued to feed sporadically throughout midday, reaching a pre-nightfall peak during which few animals were bedded. It is unknown how long after dark goats continued to feed. Rideout's (1974) radio telemetry work showed that goats remained active on both dark and moonlit nights during summer and fa ll. Chadwick (1973) observed goats feeding on moonlit nights, although he and Rideout (1974) concluded that extensive movements occurred only on bright nights. Geist (1971:262) reported that mountain goats in the Cassiar Mountains fed mostly after noon in 9 9
December and January and re tire d to nighttim e beds before dusk.
Vaughan (1975) also found feeding concentrated during afternoon while Chadwick (1973) reported pre-dusk feeding peaks during winter months.
Limited summer sightings similarly revealed early morning and evening feeding peaks, although goats fed at all hours of the day on shaded exposures. Feeding and bedding sequences were less predictable during the rutting period. AMs spent much time courting or searching for AFs and disrupted females during feeding and bedding bouts.
Anderson (1940), Brandborg (1955), Saunders (1955), Peck (1972), and
Chadwick (1973) reported early morning and late afternoon to evening feeding peaks in summer. Rideout (1974) found a pre-dawn activity peak during August which corresponded with daily minimum temperatures and moisture on vegetation, and a mid-afternoon decrease in activity corresponding with maximum daily temperatures. Relationships between daily activity and thermoregulatory demands on summer ranges in the
Bitterroot Mountains are discussed in the section on Habitat Use,
Habitat Use
E1evation. From January through May, mountain goats occupied winter ranges below 7,000 feet (2,134 m). Over 94 percent were observed on the lower 1 , 8 0 0 feet (549 m) of south-facing canyon walls between 4,200 and 6,500 feet (1,280 and 1,981 m) elevation. A complete altitudînal switch occurred in summer when 9 8 percent of observed goats were above 7,300 feet (2,225 m) elevation. The alpine cirques used e xten sively by goats in summer are located above 7,000 1 0 0 feet (2,134 m). Anderson (1940), Brandborg (1955), Hoiroyd (19&7),
Kuck (1973a), Rideout (1974), and Chadwick (1974) all reported use of lower elevations during winter than summer In Washington, Idaho,
British Columbia, and Montana. Casebeer et al. (1950), Lentfer (1955), and Vaughan (1975) found goats were at low elevations and on windblown ridgetops during w inter In Montana and Oregon. On 12 March 1975, an aerial survey of the study area provided Indirect evidence that goats use Interfluvial ridgetops above winter ranges. Three sets of tracks
In Mill Canyon and one set in Big Creek Canyon were observed on ridgetops between 7,500 and 9,000 feet (2,286 and 2,743 m) elevation; presumably all were made by mountain goats. Goats in the Swan Range o f Montana occupied the same range year-round (Chadwick 1973); goats
in Colorado showed little seasonal elevation preference (Hlbbs et al.
1969) .
Annual snow patterns influenced elevational use during winter in the Bitterroot Mountains. During the deep snow winters of 1974 and 1 9 7 5 , goats utilized mean elevations of 5,760 feet (1,756 m) and 5,700 feet (1,737 m), respectively, compared to 5,850 feet
( 1 , 7 8 3 m) during the snow-free winter of 1973- From November through
April, the mean elevation of sightings fluctuated with snow depths
(Fig. 14). Goats In the Sapphire Mountains likew ise sought lower elevations during the severe winter of 1971“72 than during the following winter (Rideout 1974). Observations of mountain goats during fall (mid-October to December)1973 and 1974 found goats approximately 700 feet (213 m) higher during the latter period. Fig. 14. Monthly mean elevation of goat sightings from 1973 to 1975.
1973
1974
1975 8000 ft
7500
7000
-2000 6500
6000
5500-
5000- -1500
MAM J A S N
M o n t h 102
Deep accumulations of snow, which blanketed the study area in October
and November 1973» forced goats from tra n s itio n a l to lower w inter ranges much earlier than during the mild fall of 1974.
The mean elevation of summer sightings decreased from 8,010 feet
(2,441 m) in July to 7,810 feet (2,380 m) in October (Fig. 14). During
July, mountain goats foraged along high ridges and ledges. By August, when cirque basins became snow-free, most sightings were in cirques.
Exposure. From the time mountain goats reached transitional
ranges in late October and November until they migrated from them
during June, all sightings were on E, SE, S, SW, and W exposures.
Sixty-three percent of all sightings were on south exposures, 23
percent on SE exposures, 6 percent on E exposures, 6 percent on SW
exposures, 1 percent on W exposures, and 1 percent indifferent.
South exposures shed snow more re ad ily than others due to favorable
sun angle and prevailing westerly winds in the Bitterroot Mountains.
Kuck (1973a) found over 90 percent of mountain goats in the Lemhi
Range on southern exposures (SE, S, SW) from November through May.
Goats used S and W exposures over 80 percent of the time in winter
and spring in the Spanish Peaks (Peck 1972), Chadwick (1973) and
Brandborg (1955) also found southern aspects favored in winter.
On my study area, goats used SE and E exposures more than SW and W, largely because of winter range geomorphology. West aspects of outcrops, cliffs, and fins were much steeper (often times sheer c liffs ), supported less forage, and received full force of strong 103 winds, in contrast to E aspects. Consequently, SE and E exposures offered more available forage and less environmental stress at a time when energy budgets were strained.
From January through April, when snow depths were greatest on winter ranges, goats frequented S exposures 56 percent of the time in 1 9 7 3 compared to 73 and 71 percent of the time in 1974 and 1975.
Annual percent use of S exposures appeared to be a function of snow depth (Table 2). Percent use of aspects was similar on winter ranges for both feeding and bedding.
As w in te r snowpack began receding in la te May and June, use of
S exposures declined and sightings on SE and E exposures increased
(Table 23). This shift was related to the appearance and accessibility of new plant growth on all exposures and thermoregulatory demands evoked by rising daytime temperatures. Easterly exposures were shaded during the warm afternoon and evening hours.
From July through mid-October, N, NE, and E exposures were exploited by goats 67 percent of the time (Table 23). Mountain goats selected these exposures 76 percent of the time for feeding. Exposures chosen for feeding were closely related to available moisture for plant growth. Lush sedge-forb mats, requiring summer-long moisture, predominated on N, ME, and E exposures in cirque basins. These herbaceous mats were favorite feeding areas of goats in summer. Melt ing snowfields persisted into August and September near the headwalls of north and east-facing cirques, providing a continuous water source.
Thermoregulation became an increasingly important biological demand 104
Table 23. Monthly percent use of exposures by mountain goats on transitional and winter (November to June 1973-1975) and summer ranges (July to mid-October 1974). Trace (T) amounts are less than 0.5 percent.
Exposure No. of Month Groups NE N E NW SE W S SW 1
Nov. 26 27 69 4
Dec. 32 6 25 69
Jan. 57 16 8 0 4
Feb. 51 4 33 59 4
Mar. 100 4 15 1 73 7
Apr. 225 5 20 2 67 5 T
May 194 9 26 2 53 9 2
June 32 16 44 31 6 3
Total 717
Averages 6 23 1 63 6 1
July 10 30 20 10 10 20 10
Aug. 41 22 17 37 17 5 2
Sept. 3 67 33 11
O ct. 9 11 22 11 11 22 11
Tota 1 63
Averages 19 19 29 14 8 5 3 3 105
during mid-summer. Goats travelling across sunny exposures in summer were sometimes observed panting. Mountain goats conducted 7 6 percent of all activities on N, NE, and E exposures during August and another
17 percent on relatively cool SE exposures. When daytime temperatures
exceeded 6 0 degrees F. (15*5 C.) in August, 97 percent of all sightings occurred on those cool exposures.
Peck ( 1 9 7 2 ) felt that occurrence of lush vegetation on north
slopes in the Spanish Peaks accounted for 50 percent use of that
exposure by goats in summer. Rideout's (1974) observations concurred.
Kuck ( 1 9 7 3 a) in Idaho and Chadwick (1974) in G lacier National Park
found little preference for exposure by goats in summer.
Slope. Mountain goats in the Bitterroot Mountains frequented
steeper slopes on winter ranges than on summer and transitional ranges
(Fig. 1 5 ) . From November to January, the mean slope used monthly by goats rose from 41 to 45 to 49 degrees. From January through June,
the average slope utilized equalled 47 degrees in 1 9 7 3 » 49 degrees in
1 9 7 4 , and 48 degrees in 1975. Monthly variation was minimal from year
to year. Goats actively sought steep portions of transitional and winter
ranges. South-facing canyon walls of four representative drainages within the study area average 23 to 27 degrees in steepness (Table 1).
Yet goats were consistently observed on slopes averaging 40 to 55 degrees during fall, winter, and spring. Steep slopes and cliffs
shed snow more readily than gentle slopes, thus exposing forage plants and facilitating travel. Steep slopes also provided secure bedsites and were equally preferred for feeding and bedding (Fig. 16). Fîg. 15- Monthly mean slope used by groups observed from January 1973 to June 1975. Degrees from Horizontal
5
3 s ^ 0 3 T
0
z
o Fîg. 16. Monthly distribution of feeding/bedding groups on slopes of tran sitio n al and w inter ranges from January 1973 to June 1975.
r I Feeding groups
^ / / Bedding groups No.of Slope In Degrees Percent Month Groups 130 31-40 41-50 51-60 61-70 >70 of Total
53 Nov. 15/2 33 50
100
58
Dec. 12/8 38 33 38 50 8 12 12 4 ; 100
47 J a n . 30/17 27 29 29 50H
- 100
45 50 Feb. 22/17 50 18 19 ------1004
M ar. 47/35 36 43 50 17 15 4 3 - 100
51 42 Apr. 74/130 28 50 20 4 3 4 4 21 jp v n - 100
37 50 M a y 58/104 30 14 13 8 2 1 - 100
53 June 8/19 38 38 50 21 25 5 11 J 2 3 3 . I 1 m ean s 47.5 EZ3 m ean = 46.8 108
On summer ranges, goats foraged and bedded along steep, snowfree
ridges In July, but preferred gentle slopes In cirque basins from August
to mid-October. The mean slope of summer sightings was 3 8 degrees.
Casebeer et al. (1950) reported 6 5 percent of goats observed along the
northern Continental Divide of Montana on steep slopes or cliffs during
summer. In the r e la tiv e ly unglaclated Sapphire Range, Rideout (1974)
recorded over 40 percent use of steep slopes and cliffs from June
through November. Mountain goats in the Lemhi Range exhibited a
pattern similar to that observed In the Bitterroot Mountains. Kuck
(1973a) found that goats used mean slopes near 6 0 degrees in winter and
spring while ridgetops of 25 degrees or less were preferred In summer
and f a l l .
In summer, goats fed on slopes averaging 34 degrees In cirque
basins, but bedded adjacent to headwalls and lateral ridges on slopes
averaging 42 degrees (Fig. 17). Chadwick (1974) found slopes of 40
degrees or more chosen 70 percent of the time for bedding and 6 5
percent of the time for feeding In Glacier National Park.
Vegetative associations. Appendix A provides a key to vegetative
associations. Understory types are described in Chapter III and
rep res en ta tiv e species o f each appear In Appendix B. Table 24 summarizes monthly use of vegetative associations from July 1974 through June
1 9 7 5 .
Due to elevational differences, vegetative associations on winter and summer ranges overlap very little . From November to June, goats used the bunchgrass type 62 percent of the time followed by Fîg. 1 7 . Monthly d istrib u tio n of feeding/bedding groups on slopes of summer ranges from July to mid-October 1974.
1 I Feeding groups
K / / I Beddi ng groups No.of Slope In Degrees Percent Month Groups n -2 0 2 1 -3 0 31-40 41-50 51-60 61-70 of Total
75 75
50 50 July 4 /4 [7^ 25 25 25 25
A 100
75 61
AugrOct. 22/15 50
22 23 23 15 15 15 25 11 8
mean = 33.85 mean = 42,ll Table 24. Monthly percent use of vegetative associations® on transitional and winter ranges from November 1974 to June 1975. Trace (T) amounts are less than 0.5 percent.
Vegetative Associations Beargrass- Deciduous Scattered Senecio- No. of Bare rock^ Snowfield^ Bunchgrass herb shrub herb sedge Month Groups 01 02 03 04 03 01 02 03 04 07 01 03 07 01 0Ï 01 02 03 04 01 03 04
Nov. 17 6 41 6 6 12 6 12 6 6
Dec. 11 9 55 27 9
Jan. 22 5 18 18 41 5 5 9
Feb. 37 11 5 24 41 5 8 5
Mar. 64 5 2 6 3 27 33 5 9 2 8 2
Apr. 148 2 2 16 10 10 32 2 1 17 1 5 2
May 96 7 3 8 8 10 24 1 1 4 5 3 10 13 1
June 22 14 5 5 5 27 14 5 14 9 5
Means 52 4 T 1 3 T 8 7 18 29 T 2 T T 1 10 1 8 4 1 1 T
Compos i te Unders to ry Means 9 T 62 3 1 23 2 Total 417
Associations receiving no use are omitted. ^ ‘Each written understory type is subtended by the numbers of associated overstory types (see Appendix A). 2 Pertinent only to May and June. 111
23 percent în scattered herb. Plant composition was similar in both understory types, but percent cover and total biomass averaged more for the bunchgrass type. The bunchgrass type covered much of winter ranges and lower elevational transitional ranges on ledges, parkland and forested colluvial slopes, and small diameter talus. Scattered herb occurred on ledges, talus, and broken rock terrain types. Use of v eg etative types was d is trib u te d most evenly in November, May, and
June when snow depths were lea s t. Bunchgrass and scattered herb received 90-96 percent of all use from December through April.
Vegetative types without overstory were increasingly selected from December through April (O to 36 percent) then dropped abruptly in
May and June (Table 24). My observations disclosed that sites chosen by goats from February through April were steep, wind-swept cliffs capable of supporting only sparse tree growth. Monthly percent use of overstory probably reflects altitudinal selection by goats rather than actual preference for canopy species. Observations of goats in
Douglas-fir and subalpine fir overstory predominated in November,
December, and June, w hile use of ponderosa pine and ponderosa pine/Douglas-fir overstory culminated in winter and early spring. The vegetative associations I employed merely evinced the presence or absence of overstory. Terrain types, discussed in the next section, better indicate stand density for comparison with habitat systems employed by other workers.
Feeding and bedding groups occurred in nearly equal frequencies in understory types with the exception of bare rock and scattered herb
(Table 25)- Table 25* Monthly percent use of understory types by feeding and bedding groups from November 197^ through 10 June 1975-
Understory Types (Percent of total feeding/percent of total bedding.)
No. of Bea rgrass Deciduous Scattered Senecio- Month Groups Bare rock Snowfield® Bunchgrass herb shrub herb sedge
Nov. 11/2^ 64/ 18/50 9/50 9/
Dec, 3/4 100/75 /25
Jan. 12/3 83/67 8/ 8/33
Feb. 17/9 82/100 6/ 12/
Mar. 32/25 3/4 66/80 6/ 25/16
Apr. 63/76 5/4 56/76 2/3 /I 38/16
May 29/55 7/25 34/45 /2 14/ 41/25 3/2
June 4/14 /29 n 50/43 25/14 25/7
Means 21/24 3/12 /I 59/65 3/2 2/1 28/19 3/1
Total 171/189
Pertinent only in May and June, to ^Number feeding/number bedding. 113
During summer, 54 percent of sightings, including 73 percent of feeding groups, were observed in the heath-herb mat understory type (Tables 26 and 27). Heath-herb mat, moist herbaceous mat, and senecio-sedge types prevailed in upper cirque basins. A lush growth of sedges, grasses, ephemeral, and perennial forbs rendered those types preferred haunts of feeding mountain goats. The heath-herb types also occurred on m eso-xeric benches and ridges between cirques, accounting fo r its dual popularity for bedding and feeding. Scattered herb ranked second in total use and first for bedding. This type grew on xeric to hydric ledges and talus. Subalpine fir and/or alpine larch were the associated overstory species in 60 percent of all summer sightings.
Twenty-seven percent lacked overstory.
Terrain types. The scheme devised to record habitat preference related to terrain features is described in Chapter III. Table 28 summarizes monthly use of terrain types from July 1974 through June
1975.
From November through June, 70 percent of all goat sightings occurred on cliffs. Kuck (1973a) found 64 to 92 percent of goats using the mahogany (Cercocarpus 1edifolius) - rock habitat type from November through May. Peck (1972) noted 59 and 70 percent use of ledge type in fall and winter. Vaughan (1975) observed sporadic use of cliff-rock habitat in winter and 60 percent use in spring in non-native goat range. Geist (1971:271) related the disproportionately high winter preference of sheer cliffs in the Cassiar Mountains by mountain goats Table 26. Monthly percent use of vegetative associations^ on summer ranges from July to mid-October 1974 . Trace amounts are less than 0.5 percent.
Vegetative Associations Beargrass" Scattered Heath-herb Senecio- Moist No. of Bare rock^ Snowfield herb herb mat sedge herb mat Month Groups 01 01 03 07 oS 01 05 07 09 01 05 07 08 09 01 05 07 09 01
July 10 10 10 10 10 10 10 10 20 10
Aug. 41 5 5 2 2 7 5 10 20 10 17 2 5 2 2 5
Sept. 3 33 33 33
Oct. 9 22 22 11 11 11 22
Means 16 6 3 2 2 2 2 2 10 5 10 16 8 16 5 6 2 2 2 3
Compos i te Understory Means 6 3 5 17 54 11 3
Total 63
^Associ at ions receiving no use are om itted.
Each written understory type is subtended by the numbers of associated overstory types (see Appendix A). Table 2?. Monthly percent use of understory types by feeding and bedding groups from July to mid-October 1974.
Understory Types (Percent of total feeding/percent of total bedding.) No. of Beargrass- Scattered Heath-herb Senecio- Moist Month Groups Bare rock Snowfield herb herb mat sedge herb mat
July 4 /3 * /6 7 75/33 2 5 /
Aug. 18/13 /1 5 / 8 / 8 6/31 72/31 11/8 11/
Sept. 2 /1 0 100/
Oct. 2 /2 /5 0 5 0 / 50/50
Means 7 /5 /1 7 / 6 / 6 4 /3 3 7 3/28 15/11 8 /
Total 26/18
’Number feeding/number bedding.
vn Table 28. Monthly percent use of terrain types^ on summer ranges (July to October 1974) and on transitional and winter ranges (November 1974 to June 1975).
Terrain Types 1C liff w/o C liff w/ Glacially Parkland Forested No. of 1promtnent prominent Slide Broken eroded colluvial colluvial Month Groups ledges ledges rock Couloir rock bedrock slope slope slope
July 10 30 10 20 10 30 Aug. 41 2 24 10 51 10 2 Sept. 3 67 33 Oct. 9 11 22 33 33
Means 3 24 14 2 3 41 11 2
Total 63
Nov. 17 47 12 6 29 6 Dec. 11 45 9 9 36 Jan. ' 22 5 55 5 5 23 9 Feb. 37 11 54 3 5 16 11 Mar. 64 19 53 5 2 14 8 Apr. 148 23 55 4 1 5 7 5 May 96 24 43 11 3 6 3 9 June 22 18 50 9 14 5 5
Means 19 51 6 2 5 10 7
Total 417 ON
Types receiving no use are omitted 117
(52 percent of observations) in comparison to Stone's sheep
(Ovis dalli stonei) ( 2 8 percent of observations) to the "general adaptive syndrome o f goats as sp ecialized rock clim bers."
Goats frequented parkland and forested colluvial slopes in fall and e a rly w in te r when snow was f lu f f y and often not as deep beneath tree canopy as on exposed te rra in . Most parkland c o llu v ia l slopes used by goats were essentially very broad c liff ledges. Chadwick (1973) noted little use of timbered areas except during movements between c liff complexes. The highest monthly use of timber (15*9 percent) in the Lemhi Range occurred in June when goats migrated through a forested transitional zone between winter and summer ranges (Kuck 1973a).
Feeding and bedding groups displayed a pattern comparable to over-all distribution within terrain types. Cliffs of transitional and winter ranges accounted for 70 percent of feeding and 71 percent of bedding activities (Table 29). Chadwick (1973) reported 95 percent of winter bedsites located on cliffs while only about 50 percent of feed ing took place there. Herbaceous forage remained available on c liff ledges in the Bitterroots throughout winter and spring months due to wind action and snowslides. Cliffs with broad, prominent ledges were more popular feeding places during fall and early winter than late winter and spring. Cliffs without prominent ledges received no use until February, but served as important snow-free feeding sites through spring. Snow collected to depths of 2 to 4 feet (0.6 to 1.2 m) on most parkland and forested colluvial slopes in winter and remained into late spring during 1975. Mountain goats avoided areas of chest deep Table 29* Monthly percent use of terrain types^ by feeding and bedding groups from July 1974 to June 1975*
Terrain Types (Percent of total feeding/percent of total bedding.) C liff w/o C liff w/ Glacially Parkland Forested No. of promi nent promi nent Slide Broken eroded colluvial colluvial Month Groups ledges ledges rock Couioi r rock bedrock slope slope slope
July 4/3^ 25/67 25/ 25/ /33 25/ Aug. 18/13 /8 17/46 /15 72/23 6/8 6/ Sept. 2/0 50/ 50/ Oct. 2/2 /50 50/ /50 50/
Means /II 19/44 4/17 4/ 4/ 58/22 8/6 4/ Total 26/18
Nov. 11/2 64/50 9/ 18/50 9/ Dec. 3/4 33/50 67/50 Jan. 12/3 67/33 /33 8/ 17/33 8/ Feb. 17/9 12/ 65/44 /II 6/33 18/11 Mar. 32/25 22/8 47/68 6/ 3/ 13/16 9/8 Apr. 63/76 33/16 42/64 5/4 2/ 5/4 9/5 2/7 May 29/55 28/18 31/49 10/13 7/2 7/7 7/2 10/9 June 4/14 25/14 50/50 /14 25/7 /7 n
Means 23/14 47/57 5/7 4/1 4/5 11/9 7/7 Total 171/189
^Types receiving no use are omitted.
CXD Number feeding/number bedding. 119 snow unless it supported their weight. As a result, these terrain types were seldom visited from April through June. Foss (1962) and
Vaughan (1975) observed goats in timber during inclement weather.
Mountain goats in the Wallowa Mountains became dependent on open timber habitat in March when food supplies on adjacent winter range were depleted (Vaughan 1975). Mountain goats in the B itte rro o t Range retreated to the lee side of cliffs and fins or sought out caves during winter storms. There were at least five caves on the Fred Burr winter range and several others were located on winter ranges and summer ranges in other drainages. Carpets of pellets, shed hair, and tracks evidenced the importance of caves and protective overhangs as shelter for mountain goats. I occasionally observed goats feeding on shrubs and conifers in parkland and forested terrain during winter and spring. As snowbound slide rock and couloirs became accessible in spring, goat utilization of these terrain types rose. Percent use of cliffs with and without prominent ledges remained high in May and
June as they were among the first places to "green-up."
Escape terrain pervades winter ranges, and therefore was not a primary factor determining the location of bedding areas. In general, goats chose gently sloping ledges and outcrops fo r bedding. The most significant feature or bedsites was the view they commanded. As
Chadwick (1973) reported, bedsites at the bases of c liff walls were popular. I found repeated bedding on the brink of outcrops and ledges
(cliffs with and without prominent ledges), along the crest of fins
(broken rock terrain type), and on unforested boulder fields 1 2 0
(slide rock). All of those areas provided a view in front and to both sides and precipitous cliffs or an open slope behind. Couloirs were avoided, and a high point, preferably a large boulder, was chosen for bedding in forested terrain.
On summer ranges, glacially eroded bedrock slopes, prevalent in upper cirque basins, and cliffs with prominent ledges constituted
6 5 percent of all sightings. Slide rock and parkland colluvial slopes received 14 and 11 percent use, respectively (Table 28).
Food is an unlimited resource during summer. However mountain goats tended to concentrate feeding on terrain supporting the most lush vegetative cover. As snowfields receded in late July, goats retreated to cirque basins from exposed colluvial slopes and ledges.
From August to mid-October, 68 percent of feeding groups were on glacially eroded bedrock slopes (Table 29). Lengthy observations of individual groups during summer revealed that even more time, than the 68 percent figure indicates, was spent in this terrain type.
Glacially eroded bedrock slopes sustain extensive sedge-forb meadows irrigated by snowmelt. Deep snow persisted into June 1974, and I found shaded sections of cirques choked w ith as much as 20 fe et
(6.1 m) of snow in mid-July (Table 2). This delayed plant phenology.
During a normal year, goats may utilize glacially eroded bedrock slopes more in ten siv ely in July,
After feeding bouts, goats generally retired to c liff ledges or slide rock terrain at the headwalls or lateral ridges of cirques to bed. Twenty-two percent bedded on glacially eroded bedrock slopes. 121
Mountain goats in Glacier National Park preferred ledge terrain
for both bedding and feeding in summer, but talus slopes became
increasingly important during late summer for feeding (Chadwick 1974).
Peck ( 1 9 7 2 ) correlated high summer use of ledge and slide rock habitat
types to available moisture for plant growth. Saunders (1955) and
Foss (1 9 6 2 ) also recorded high use of slide rock. Casebeer et al.
( 1 9 5 0 ) related summer use of alpine openings and ledges to forage
abundance, Hjeljord (1971), Vaughan (1975), and Kuck (1973a) noted
high use of ridgetops in early summer, but attributed a shift to
meadows and slide rock to desicatlon of forage on ridges. Only in a
largely forested goat range in the Sapphire Mountains was significant
use of forest reported during summer or fall (Rideout 1974). Most of
Rideout's data points were derived from radio-telemetry locations and
may portray a more accurate utilization of forested terrain than
observational data obtained by other investigators.
Patterns of habitat use and distribution on the Fred Burr winter
range. In general, preferred feeding habitat was also preferred bedding
habitat on winter ranges. Snow depths influenced the terrain chosen
for both activities. During the mild fall and early winter of 1974-75,
parkland colluvial slopes and cliffs with prominent ledges yielded
abundant forage and accounted for 85 and 8 9 percent of feeding and
bedding sightings, respectively. In deep snow, energy expenditures are
high during tra v e l and feeding because movements are cumbersome and goats must paw fo r herbaceous forage. Geist (1971:266-268) f e l t that pawing
frequencies of Stone's sheep and mountain goats reflected the relative 122 effort being expended. He observed that both pawing frequency and number of scratches per bout increased with snow depth. Goats sought lower elevations and steeper slopes in winter and early spring. They maximized food intake by avoiding terrain types covered by deep snow, such as couloirs, slide rock, and most colluvial slopes, and utilized relatively snow-free c liff ledges. Cliff ledges also provided optimum bedsites, as discussed previously, thus goats further conserved energy reserves by bedding where they fed. Vaughan (1975) felt that inadequate winter range forced mountain goats to bed at low elevations
In timbered areas and feed on wind-swept ridgetops in the Wallowa
Mountains. He hypothesized that the herd's low reproductive success partially resulted from the adverse effect traversing twice daily between these areas had on gravid females.
While synchronizing daily activities on snow-free portions of cliffs or "key areas" appears to create a favorable balance between energy intake and output, such habitat utilization may in actuality be less fortuitous. Concentrated use on "key areas" of winter range locally depleted food supplies in Fred Burr Canyon during 1975
(see Food Habits). Brandborg (1955) also reported forage depletion on winter concentration areas.
Petocz (1973) reported that severe winter conditions encouraged goats to aggregate, thus reducing the number of single animals and increasing the incidence of mixed groups. He regarded high frequencies of agonistic behavior patterns, observed in winter, as a manifestation of intraspecific competition related to snow depth. I did not record 123 and q u an tify aggressive In teractions and thus cannot compare, from a behavioral standpoint, the degree of intraspecific competition on winter ranges. However, yeai—to-year distribution of hierarchial groups on winter range indicates that mountain goats in Fred Burr
Canyon responded to environmental conditions in a different manner
than those Petocz studied.
During the mild winter of 1973, an estimated herd of 36 goats was distributed across 3-1 miles (5 km) of winter range (Table 30 and Fig. 18). Snow restricted neither travel nor food availability
Table 30. Distribution-related data for mountain goats on the Fred Burr winter range from January to 27 May 1973“75- Nearest- neighbor (N-N) distances, in yards (m ), were measured from topographic maps and not adjusted for elevational change.
Year 1973 1974 1975
Herd Size 36(29) 32 27 Mean Gp. Size 2.18 1.45 1.47 Av. No. Gps. on W inter Range^ 16.4 22.0 18.4 Linear Area of Winter Range Used 3« I m l(5 km) 4 .2 (6 .8 ) 4 .2 (6 .8 ) Mean D is t. to N-N of AM Gps. 379(347) 450(411) 565(517) Mean Dist. to Nearest AF Gp. from AM Gps. 679(621) 1381 (1263) 1184(1083) a Herd sizefmean group size; the herd estimate of 36 goats for 1973 is used to calculate average number of groups. and goats exploited a wide range of elevations, exposures, and habitats wintei—long. Forty-seven percent of groups were single animals. Deep snow restricted travel and food availability during winter 1974. Fîg. 18. Linear distribution of goat sightings across the Fred Burr winter range from January through May 1973"1975. Fig. 6 shows the axis from which distances were measured.
AF groups (groups containing one or more AFs but no AMs)
AM groups (groups containing one or more AMs but no AFs)
/ / / Mixed groups (groups containing at least one AF and one AM) I mean = 1365 8 8 1973 Q mean = 1329 6 6 mean = 1783 4- h4 2- 2 n ■ A - k D - i ^ I ■ J L
8 H mean = 1370 8 lA 1974 a 6 6 0 mean = -749 0 4 •4 k mean = 3850 0 2 2 □ □ nn h f e
18 18 0 16 16 Z g mean = 2098 144 1975 14 mean = 1184 12 12 10 mean= 1010 10 8 8 6 6 4 4 2 2 n II
Linear Distance in Yards (Meters) 125
Groups containing AFs, particularly those with Ks, monopolized "key areas" on cliffs. Subdominants, particularly AMs, avoided areas frequented by AFs. When they encountered each other, AFs often acted aggressively and repelled AMs. The amount of winter range used increased to 4.2 miles (6.8 km). While AFs remained winter-long on the eastern 3 miles (4.8 km) of winter range, 8 3 percent of AM sightings were on the western 1 mile (1.6 km) where snow was much deeper (Fig. 18). Consequently, the mean distance from AM groups
(groups containing one or more AMs but no AFs) to their nearest- neighbors and to the nearest AF group (groups containing one or more
AFs but no AMs) rose from that of the previous year. This happened despite the fact that mean group size declined, 71 percent of all groups were singles, and the average number of groups on the winter range increased (Table 30). Winter 1975 was another with deep snow.
Prolonged cloudy weather in April and May retarded snowmelt. A herd o f 2 7 goats occupied 4.2 miles (6.8 km) of winter range. The pattern of distribution was comparable to 1973, offset by a clump of AF sightings on the eastern mile of winter range, and a clump of AM sightings on the western portion (Fig. 18). The distinct east-west segregation of AFs and AMs of the previous winter disappeared.
Nevertheless, mean distance from AM groups to their nearest-neighbors increased over the previous 2 years. The mean distance from AM groups to AF groups was only somewhat less than in 1974. Group size remained small and 6 9 percent of all groups were singles. These data prompt several theories: 126
1) Snow conditions influence group size on the Fred Burr winter range. Mean group size was large (2.19) during winter 1973 possibly because low intraspecific competition for feeding areas resulted in low intraspecific aggression and greater group stability. Group sizes averaged smaller and the proportion of single goat sightings was 55 percent higher during the 2 ensuing winters.
2) Snow conditions influence the size of winter range occupied by the Fred Burr herd. Although herd size was probably larger during winter 1973 than the following winters, 0.25 less linear range was used. Shallow snow conditions reduced competition for snow-free feeding areas and promoted extensive use of the eastern 3 miles
(4.8 km) of winter range.
3) The existence, location, and significance of "key areas" depend upon snow conditions during a given year. During winter 1973, extensive use of winter range occurred. Of 77 sightings in Fred
Burr Canyon from January through May, no two were at the same location.
During the following 2 winters of deep snow, goats practiced intensive use of winter range. "Key areas" were recognized as sites which goats repeatedly used.
4) Annual snow conditions a ffec te d the incidence of mixed groups (AM-AF) very l i t t l e . Percentages o f mixed groups of a ll sightings during the winters of 1973, 1974, and 1 9 7 5 were 4.8, 2.2, and 4.8 percent, respectively. Mixed groups were unstable during all
3 years.
5) During winters of deep snow, the distribution of socially subdominant classes was more variable than that of dominant classes. 127
My observations concur with those of Geist (I9 6 A), Chadwick (1973)»
and others that outside the rut, AFs are socially dominant to other
classes and that AMs are subordinate to all others. Chadwick (1973)
also regarded the inability of mature males to interact successfully
in fema 1e-subadult groups as encouraging a "...largely solitary
existence and extensive travelling by older males." In Fred Burr
Canyon, AFs successfully exploited "key areas" of winter range.
AMs eschewed oth er goats on w in te r range and avoided "key areas"
when occupied by other goats. However, the distributional pattern of
AMs was inconsistent between winters. During winter 1974, AF and AM
groups were segregated east-west on winter range, but in 1 9 7 5 , lin e a r
segregation was less significant. Instead, AMs used suboptimal
habitat on the eastern 2.5 miles (4 km) of winter range (Fig. 18).
Lower herd density and reduced likelihood of confrontations with
other groups may be responsible fo r the changed d is trib u tio n o f AMs
during the latter winter. Chadwick (1973), Rideout (1974), and
DeBock ( 1 9 7 0 ) observed AMs occupying winter areas peri feral to AFs
and subadults. Kuck (pers. comm.) found that "key areas" within the mahogany-rock habitat type continued to support nearly constant
numbers of goats each winter as the population in the Lemhi Range
declined. He felt goats moved into these areas from marginal habitat.
Predicting habitat selection. Habitat selection by mountain goats in the Bitterroot Mountains is dependent upon a complex weave of environmental variables ultimately related to gross geomorphology and climatologica1 patterns. Goats appear to favor particular 128 vegetative associations during snow-free months, but forage accessibility dictates habitat selection when snow blankets the ground.
On winter ranges, either one or both of the two most frequently used understory types, bunchgrass and scattered herb, occur on all seven terrain types. Yet two of those terrain types, cliffs with prominent ledges and cliffs without prominent ledges, received over 70 percent of all use on winter ranges. Grassy, wind-swept ridges, reported by
Casebeer et a l. (1950), Lentfer (1955)» Hibbs et a l. (1969), Chadwick
(1973), and Vaughan (1975) as important winter feeding areas, are non-existent in the study area. In the Bitterroot Mountains, c liff ledges support abundant forage, provide secure bedsites, and shed snow more readily than other terrain types, thereby facilitating feeding and travel. Most parkland colluvial slopes utilized by goats on winter ranges were essentially very broad ledges on cliffs. These received significant use in early winter when blown free of fluffy snow. Thus, while snow restricts exploitation of other terrain types, goat distribution on winter ranges is predictable from the location of favorable c liff terrain.
Habitat selection during summer is less predictable on a miscroscale than in winter, because biological requirements of mountain goats are satisfied in a variety of habitats distributed over vast areas. On a gross scale, upper basins and surrounding ridges of alpine cirques receive most use. Casebeer et al. (1950), Peck (1972), Kuck
(1973a), and Vaughan (1975) rela ted summer h a b itat use to location of lush forage. Cirque basins in the study area achieved primary 129 importance as they became verdant following snow recession; this varies with annual weather patterns. Habitat distribution of feeding groups seemed related to vegetative associations (88% in heath-herb mat and sencio-sedge types) while bedding was not. Two terrain types, glacially eroded bedrock slopes and cliffs with prominent ledges, accounted for 77 and 66 percent of feeding and bedding sightings, respectively. Ultimately, vegetative associations are determined by a combination of physical factors, of which elevation, direction and steepness of slope, and terrain type are most important. Therefore, fam iliarity with the topographic distribution of vegetative associations, enables fair prediction of summer habitat selection of mountain goats from terrain types.
Migrations and Winter Range Fidelity
Seasonal migrations from winter to summer ranges covered 10 miles (16 km) or less. Migrations were vertical as well as horizontal
(see Seasonal Distribution). Winter ranges lay 6-10 miles (9*7”16 km) from summer habitat along the Bitterroot Divide. Movements to summer ranges along interfluvial ridges required shorter migrations unless goats crossed one or more trunk canyons. During summer, goat sign was infrequently encountered in canyon bottoms, indicating that goats spent little time there while migrating or otherwise. Ground observations of movements, and tracks discovered in snow and earth revealed that goats dispersed in several directions from winter ranges
(Fig. 19). This multi-directional dispersion,promoted extensive rather than intensive distribution on summer ranges. Fig. 1 9 . The pattern of spring migration from winter ranges to summer ranges pursued by mountain goats in the Bitterroots (shown for Big Creek Canyon). The 1974 migration route, summer home range, and summer high use area of AF, Nan (Fred Burr Canyon).
Migration route
Summer home range boundary
— . — Summer high use area boundary
8 June 1 9 7 4 relocation of Nan on Fred Burr winter range
First relocation on summer range 12 July 1 9 7 4
Second relocation on summer range 8 August 1 9 7 4
First relocation on Fred Burr transitional range following fall migration 17 October 1974
F irs t relocation back on w in ter range 29 November 1974 . I
4 Heavenly' / ,lk ily v in s SI Mary ' / . - — - — _ / t ,4 Ranger stormy P k ^ g f ) ^ kumf M wrnAl g f * ^ r T ORTH a a i À I ] ' ' in 3i?
\ Ml}
\ s . I 'X 'l _ i I M A fff StjTixJ louth htrk V I
W Ï79 »H H Sky .> Pilot 1
I P a r ^ h u t r
^%?%iTiERAobf% : r^'L_&:
l»i 0 Totem 1 I "'"k:T(yX'-. I, U3»f (W
I M rJ /K frj
“ \l &9Hr C' ■ f d U BfrrmWborriL^ | \ WILQfLOWfR
| \ ; ^ Ü u tcti ,
/ 4 /Jv *M |II /^J*r Printz ^ / Pi _L/,/«n ■ ■" ' iv-f*— BL|OOG£fr «row ^ I . { . H .' ‘ • lli •• •< :■ t f ' ■ • :.) T - ' V ' " - : l - ' - ’X '■*,
f î ^ ÿ c ; - r ..
•’ ;| Jlaniilton*’ Downing " 1 ii •■■ ' > . > -r , 131
Goats and th e ir sign were common along both the Montana and Idaho sides of the Bitterroot Divide. Brandborg (1955) reasoned that some goats which summered on the Selway River slopes in Idaho migrated to the lower Bitterroot Canyons for the winter. Suitable summer habitat both east and west of the Bitterroot Divide is continuous. Some goats, born and spending winters in Montana, probably migrate 10 miles
(16 km) or more across the Bitterroot Divide during summer. All or part of the months from July to October could be spent in Idaho, implying that each fall Idaho hunters may shoot goats produced in
Montana before they return to their Bitterroot winter ranges.
M igrations between separate seasonal ranges also occur in
Washington (Anderson 1940), Idaho (Kuck 1973a, Brandborg 1955), Alaska
(Klein 1953, Hjeljord 1971), British Columbia (Holroyd 19^7, DeBock
1 9 7 0 ) , and Montana (Casebeer et a l. 1950, Peck 1972, Chadwick 1974).
Seasonal migrations covered only 1-3 miles (1.6 km-4.8 km) in the
Lemhi Range as goats summered on ridgetops adjacent to lower w inter ranges. Where adequate summer and w in te r hab itat are fa rth e r removed, migrations cover greater distances.
Nan, a 3-year-old AF, captured and radio-instrumented on the
Fred Burr winter range on 14 April 1974, provided information on migration (Fig. 19)- On 8 June 1974, she was radio-located on winter range. Aerial telemetry fixes on 12 July and 8 August found her on the timbered n o rth-facin g wall of Fred Burr Canyon. Nine a e ria l or ground relocations in August and October centered around the Castle
Crag mountain complex, 5 airline miles (8 km) southwest of her 8 June 132 position. On 17 November, she showed up on transitional range in western Fred Burr Canyon. Tracks of an AF and 2 Ys, believed to be Nan and her Y companions from October, were found on 13 November. They descended the north-facing canyon wall and crossed Fred Burr Creek directly between Nan's 12 July and 17 November 1974 positions. She had apparently retraced her spring migration route. When next observed on 29 November 1974, she was back on Fred Burr w in ter range and remained there into June 1975- Other goats, individually recognizable by horn morphology, also exhibited fidelity to the Fred Burr winter range.
AF Alpha, who sported long, widely divergent horns, and Captain Hook, an AM possessing thickset horns which curved abruptly over his skull, both returned to Fred Burr in 1975 after residing there the previous winter. Nubs, originally observed as a Y during winter 1973, returned to Fred Burr as a 2-year-old and 3-year-old. Nubs had two broken horns crowned w ith round knobs. I t remains unknown how many goats occupying the Fred Burr winter range in 1973 returned in subsequent years; earnest efforts to identify individual animals began in 1974. AF Beta, who was distinguished from other AFs on the Fred Burr winter range in
1975, possibly wintered there the previous year. However, her horns were insufficiently unique to be certain it was the same animal. Only one goat, an AF with a forward-curved left horn, recognized in 1974, was not seen in 1975. On two censuses during January 1976, this AF,
Nan, Nubs, Alpha, and Captain Hook were all reobserved on the Fred
Burr winter range once again. Too few censuses were conducted each year to substantiate fidelity to winter ranges in other drainages. 133
Brandborg (1955) discussed the tendency of goats to return to the same winter ranges each year, including a broken-horned AF observed during 3 consecutive years. In the Lemhi Range, marked AFs
returned to the same w in te r ranges each year. However, AMs traveled between winter ranges during the rut and wintered on whichever range they happened to occupy at the close o f the rut (Kuck pers. comm.).
Without several identifiable AMs, it was impossible to ascertain winter range fidelity of this class in the Bitterroots. Following his
capture, a transmitter signal was never received from the only AM which I captured and radio-instrumented. That AM was never seen or heard from again. Captain Hook, the only individually recognizable
AM, wintered at least 3 consecutive years (1974-76) in Fred Burr Canyon.
Perennial fidelity to winter ranges by AFs versus haphazard or
inconsistent fidelity by AMs would help to explain the traditional exploitation of "key areas" by AFs while AMs used less optimal range and exhibited inconsistent distribution from yeai—to-year in Fred
Burr Canyon (see Patterns of habitat use and distribution on the Fred
Burr winter range.). Going one step further, Ks born to AFs from the
Fred Burr herd, for example, would return to Fred Burr for their first winter. A learned response then develops which draws them back to
Fred Burr each succeeding fall. The pattern may endure life-long for females, while many sexually mature males, because of their searching for receptive mates, would be less inclined to return to matriarchal ranges each fa ll. 134
Brandborg (1955) and Anderson (1940) considered the timing of
fall migrations correlated with environmental conditions on summer
ranges. Brandborg stated that 2 or 3 days following accumulations of
snow at higher elevations, goats appeared on winter ranges along the
Salmon River. Migrations were delayed until November during mild
falls. Heavy snowfall across the study area on 31 October and 1
November 1973» forced goats onto w in te r ranges in early November.
Fall 1974 was exceptionally warm and dry. Little snow fell until
late December, yet mountain goats appeared on transitional and winter
ranges during la te October and November, p rio r to the ru t. Although
deep snow, which reduces food availability, probably triggers migra
tions from summer ranges during most years, fall migrations apparently
precede the rut regardless of weather conditions. An innate response
to photoperiod or physiological changes precursive to the rut
probably induces migrations in mild years.
Spring migrations took place in June. In 1974 and 1975» animals
of all classes were observed on the Fred Burr winter range during
early June, following a late spring each year. Subadults and AMs
seemed to depart somewhat earlier in 1973- All AFs were believed to
kid on winter ranges, thus delaying their departures until mid- to
la te June.
Seasonal Movements
Seasonal home ranges. Seasonal home ranges were delineated for six individually recognizable mountain goats of the Fred Burr herd.
The 1975 w intei—spring home ranges were established for four AFs 135
(Nan, who was radio-înstrumented, and Alpha, Beta, and Nubs who were
recognized by th e ir horns) and one AM, Captain Hook, and one Y, Sigma, with distinctive horns (Figs. 20 through 24). In addition, 1974 w in te r-s p rin g home ranges were mapped fo r Nan and Nubs. A minimum of eight relocations (only one per day), all obtained during ground
censuses, defined each seasonal home range. Fewer relocations for
Alpha and Captain Hook in 1974, and Nubs in 1973, were plotted on maps of their respective seasonal home ranges.
Mountain goats moved onto w in te r ranges in the study area during
late fall. However, not until the rut ended did most individuals
settle down to their winter-sprÎng home ranges. Thus, locations from
January through June were used to map wintei—spring home ranges.
However, during late May, AFs moved to kidding grounds, which, for
some, were not within their wintei—spring home ranges during previous months. Thus, wintei—spring home ranges for AFs and also for Y Sigma - who followed Nan to kidding grounds in 1975 ” were also calculated using only locations from January through 23 May (Table 31). A summer
home range was delineated for Nan from six ground relocations and five telemetry fixes.
Table 31 shows sizes of seasonal home ranges. Areas are not corrected for relief but providea relative comparison of size.
Wintei—spring home ranges of AFs were largest followed by those of a
Y, AM, and 2F. I observed Captain Hook, the AM, only four times prior to 26 May during 1975- AMs on the eastern portion o f w in ter ranges generally occupied higher, less visible terrain than AFs. Consequently, Fig. 20. Winter-spring home range of Y Sigma during 1975» All relocations from January to June included.
Boundary 1 m ile
7000 FEET
1 KILOMETER
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL Fig. 21. Wi nter-spr I ng home range of AF Beta for 1975
------Boundary (
I
4772\y^ = =-==^ = 4600
6800 SCALE 1.24CXX) 0 1 m ile
7000 FEET
1 KILOMETER
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL Fig. 22. Winter-spring home range of AF Alpha for 1975 and sequential relocations of her during 1974. All relocations from January to June included.
------Boundary
1 - 5 1 9 7 4 relocations L
6800 1:24000 1 mile
3000 4000; 7000 FEET 1 k ilo m e te r
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL Fig. 23- Winter-spring home ranges o f AF, Nan, fo r 197^ and 1 9 7 5 . Ail relocations from January to June included
1 9 7 4 boundary
1 9 7 5 boundary 6600
KILOMETER
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL Fîg. 24. W inter-spring home ranges o f AF, Nubs, for 197^ and 1 9 7 5 (left), and of AM, Captain Hook, for 1975 (right) All relocations from January to June included. Also shown are sequential relocations of Nubs during 1973 (1 - 3 ) and one relocation for Captain Hook during 1 9 7 4 (4).
1 9 7 4 boundary
1 9 7 5 boundary
1 " 3 1 9 7 3 relocations of Nubs
4 1 9 7 4 relocation of Captain Hook / y Fred Burr Res
—5-400 4600
SCALE 1.240ÔÛ 0 1 WLE
7000 FEET
1 KILOMETER
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL Table 31* Seasonal home ranges and high use areas for six recognizable goats of the Fred Burr Canyon herd.
Seasonal Home Ranges High Use Areas % of Relocations No. of Dates of S1 ze Relocations from Jan-23 May Size Goat Sex Age Year Relocations Relocations a/ha No. In Each Ranges a/ha
Sigma FY 1975 17 1/11-6/7 109/44 11 1/11-5/23 82/33 1 8 73 3.8/1.5 Captain Hook M Ad. 1975 8 3/2-6/5 55/22 1 6® 75 7.6/ 3.1
Beta F Ad. 1975 16 1/18-4/30 126/51 2 12 (8,4) 75 12.1(6.7,5-4)/ 4.9(2.7,2.2)
Alpha F Ad. 1975 19 1/6-5/30 134/54 17 1/ 6- 5/16 120/49 2 13 (7,6) 76 14.9 (5.6,9 .3)/ 6.0(2.3,3.8) Nan F 4 14 1/ 19 - 6/7 178/72 yrs. 1975 9 1/ 19 - 5/23 83/34 1 7 78 7.2/ 2.9 3 10 4/14-6/8 162/66 yrs. 1974 9 4/ 14- 5/23 97/39 2 7 (4,3) 78 5.9(0.7,5.2)/ 2.4(0.3,2.1) Nubs F 3 yrs. 1975 15 1/ 6- 5/13 90/36 1 11 73 11.5/ 4.7 2 10 1/ 19 - 6/1 54/22 yrs. 1974 8 1/ 19- 5/20 44/18 1 6 75 17.2/ 7.0 Avg for AFs 1974-75 14.3 Jan-June 158/64 Avg for AFs 1974-75 13.2 Jan-23 May 103/42 5*’ 10 76 10.3/ 4.2 Nan F 4 yrs. 1974 11 7/ 12- 10/17 1456/589 8 73 580/235
'Four relocations obtained between 26 May and 5 June, 1 per AF(for those AFs having 2 high use areas, the combined areas are averaged under Size a/ha). 142
they were less frequently seen. Due to the configuration of the Fred
Burr winter range, seasonal home ranges were linear in shape.
Exceptions were the 1974 and 1975 ranges o f Nubs, who apparently wintered in the same 0.5 mile (0.8 km) long section of the canyon for
3 consecutive years. Winter-spring home ranges of Alpha, Beta, and Nubs
covered 2 or more linear miles (3.2 km). Other goats also traversed a
substantial length of winter ranges. Nevertheless, the measured areas of winter-spring home ranges were 178 acres (72 ha) or less since winter
ranges were steep and narrow from north to south.
Nubs was first observed as a Y in 1973 on the Fred Burr winter
range. Her return to and residency on the same cliffy area during the
following 2 years implies seasonal home range fidelity. The 1975 winter-spring range of Alpha circumscribed all five observations of her
the previous year, but only 40 percent of relocations of Nan during
1 9 7 4 fell within her winter-spring home range of 1975. The reason for
this discrepancy is unclear. Regarding elk in Yellowstone National
Park, Craighead et al. (1973) stated that . . calves probably learn
th e ir mothers' seasonal movements, thus, each new generation tends to be 'tied' to a specific land area providing continuity and stability of seasonal ranges." This seems applicable in the case of Nubs and possibly Alpha. Each may have wintered as a K on the same seasonal
range to which she traditionally returned each year. Other individuals, such as Nan, displayed f id e l it y to the Fred Burr w inter range but not necessarily to a discrete winter-spring home range. A larger sample of marked goats is needed to c la r if y seasonal home range f id e l it y by sex and/or age class. 143
Nan's summer (July to mid-October) home range was over eight times larger than her 1974 and 1975 winter-spring home ranges.
Telemetry fixes on 12 July and 8 August 1974 located her at the northern edge o f her summer home range (Fig. 19). Nine subsequent ground and aerial relocations of Nan centered around Castle Crag in alpine cirques.
Other recognizable members of the Fred Burr herd were not seen on summer
ranges. Rideout (1974) calculated summer-fall (16 May to 15 November) home ranges of goats in the Sapphire Mountains. He found a mean size o f 1 9 . 8 km^ or 1,980 ha (7.6 mi^, 4,890 a) for five AF ranges - 3.38
times larger than Nan's. However, Rideout derived his home ranges from an average of 67 telemetry fixes per animal. Rideout found summer-fall 2 2 home range sizes averaged 41.2 km (10,178 a) for Ys, 17-8 km (4,347 a) for AMs, and 15.9 km^ (3,927 a) for 2-year-olds.
High use areas. Although winter-spring home ranges averaged over
100 acres (40 ha) in size and generally overlapped, most relocations were clustered on one or two much smaller portions of home ranges I called "high use areas." Those areas were steep, southern exposures scattered the length of the winter range (Fig. 25). I previously described such locations as "key areas" of habitat. Seventy-five percent or more o f my observations of AFs and Y Sigma (who spent March to June w ith Nan) clustered on one or two "high use areas" measuring
3 . 8 - 1 7 . 2 acres (1.5“7-0 ha) in size (Table 31). From January to early
May, I repeatedly observed mountain goats on these and comparable high use areas on the Bitterroot winter ranges. The actual percentage of time individual goats spent on high use areas probably was somewhat less Fig. 2 5 . High use areas for six mountain goats of the Fred Burr herd for 1975. Y Sigma's high use area coincides with the southern one half of Nan's.
N - Nubs A - Alpha B - Beta H - Captain Hook NAN - Nan 6900 SCALE 1.24 OÔÛ 0 1 mile
7000 FEET
I Kilometer
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL 145
than the percentages of locations recorded there. Those cliffy areas were mo re v is ib le from vantage points in canyon bottoms than were other
terrain types. Occasional censuses, primarily during inclement weather, which yielded counts of only four or five goats bear witness to the use
of more obscure portions of winter ranges.
A.given high use area was primarily used by one or two goats, but
others, while traveling across their home ranges, also used the same
areas. However, groups larger than four goats, or several small groups were seldom seen together on high use areas or elsewhere; goats tended
to distribute themselves evenly across winter ranges.
Nub's high use area remained constant from 1974 to 1975 (Fig. 26).
Two of three observations of her during 1973 were on or adjacent to
that high use area. Three of the four 1974 observations of Nan, which
coincided with her 1975 winter-spring home range, fell within her 1975
high use area. Traditional attachment to a high use area may transcend attachment to a seasonal home range. Therefore, home range boundaries may fluctuate from year-to-year in relation to an animal's high use a re a (s ). Compared to AMs, w in te r high use areas used by AFs would probably remain more constant from year-to-year due to their social status. Deep snow during severe winters or pressures from conspecifics might force socially subdominant AMs from their high use areas.
A high use area, encompassing 73 percent o f relocations w ith in her 1 9 7 4 summer home range, was delineated for Nan (Fig. 19). It exceeded her 1974 and 1975 w in ter high use areas in size by 9 8 and
8 0 times, respectively. This reflects the greater mobility of goats Fig. 26. High use areas for Nubs (N) and Nan (NAN) during 197^ A
f>000
Fred Burr Res -
<,7Ti
00~-—
SCALE 1.240Ô0 0 1 mE 1000 0 1000 2000 3000 4000 5000 6000 7000 FEET s r s z B 1 KILOMETER
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL 1 4 7 and wider distribution of suitable habitat on summer than winter ranges in the Bitterroot Mountains.
Daily movements. Movements of goats on winter ranges were minimal. Snow choked couloirs obstructed winter travel and goats frequently remained for several days on a 5-20 acre (2-8 ha) section of c liff. During mid-February 1975» Sigma remained on the same 0-5 acre
(0.2 ha) cliffy area for at least 4 consecutive days. Brandborg (1955),
Hibbs et a l. (19&9), and Chadwick (1973) reported that goats often remained in confined areas for several days or weeks at a time.
Brandborg (1955) noted a group of 10 goats which spent 3 months (February to May) on a winter range of less than 200 acres (81 ha) along the
Salmon River.
Even when snow began receding in A p r il, goats generally remained sedentary. From 29 March to 11 A p ril 1975» I censused the Fred Burr winter range five times. On each census. Nubs was on the same 1.8 acre
( 0 . 7 ha) portion of her high use area. On seven censuses of Fred Burr
Canyon between 17 and 30 April 1975» I observed Alpha using a 5*6 acre
( 2 . 3 ha) portion of her high use area. In each of these examples, the intensive use focused on cliffs with or without prominent ledges and/or parkland colluvial slopes. Prior to May, high use areas of all AFs and some subadults and AMs typically coincided with such optimum habitat.
Daily movements exceeding 400 yards ( 3 6 6 m) were rare on winter ranges prior to May, but thereafter became common. One notable exception was a 2.2 airline mile (3 5 km) distance recorded between locations of
Beta on 18 and 19 January 1975- At points along the 4 mile (6.4 km) 148
length of Fred Burr and other winter ranges in the study area, vertical walls and fins often created barriers with only one or two traversable
routes east and west within the elevations frequented by mountain goats.
Goats obviously were familiar with those routes, yet I found repeated gains and losses of elevation and considerable time and energy were
necessary to travel long distances across winter ranges. In the eastern
portions of Fred Burr, M ill, and Blodgett canyons, gently-sloping,
forested ridgelines crest the south-facing canyon walls. Tracks
discovered from the air and on the ground indicated that mountain goats
traveled those rîdgetops when moving from east to west on winter ranges.
Droppings, shed h a ir, and heavy browsing of shrubs revealed that a s trip of ridgetop, adjacent to the south-facing cliffs in Fred Burr Canyon,
received use by mountain goats as well as deer and elk.
On summer ranges in the Bitterroot Mountains, mountain goats
tra v e le d fre e ly between cirque basins, but sometimes lingered in the same cirque for several days. Observations of Nan indicated that she traveled a circular route around Castle Crag. She was seen at least once in each o f the fiv e cirques surrounding that peak during August and October 1974. Hibbs e t a l. (19&9) reported a s im ila r pattern o f summer movements in Colorado. Chadwick (1973) found rates and distances traveled while feeding increased during summer as goats became selective grazers and snow did not impair feeding. The same trend p re v ailed in the B itte rro o ts . Goats maintained a steady pace while
feeding and sometimes hurried across bedrock to the next pocket of vegetation. Both snow and topography depressed rates and distances of travel while goats fed during winter and spring. 1 4 9
Food Habits and Food A v a ila b ility
Rumen analyses. Rumen samples from nine mountain goats provided information on seasonal food habits. Hunters killed six goats on summer ranges in District 240 between 15 September and 19 October 1974, and two on transitional ranges in Fred Burr Canyon on 5 October and
22 November 1974. The ninth animal was a w in t e r - k ill (No. 5, Table 19) believed to have died during March or A pril on the Fred Burr w in ter range. Results of analyses were expressed as percentages of the total volume of samples (Table 32), Percentages of species composition for each sample collected on summer ranges were averaged for the six rumen samples. The same procedure applied to the two samples from transitional range.
Grasses, sedges, and rushes comprised over 70 percent of rumen contents from summer and winter ranges and 62 percent from the transi tional range. Bluebunch wheatgrass (Agropyron spicatum) constituted
42.9 percent of the winter range sample. Casebeer et al. (1950) reported that bluebunch wheatgrass made up 48 percent of the winter diet of goats in the Rattlesnake drainage, north of Missoula, and 52 percent in the Red Butte area of Montana. He stated that bluebunch wheatgrass was a highly preferred species in both places. Forbs composed 26.1 and 34.7 percent, respectively, of summer and transitional range rumen samples. St. John's-wort (Hypericum formosum) was the single most common forb in rumens from summer ranges; it constituted
27 percent of one sample and occurred in four others. Beargrass
(Xerophyllum tenax) leaves made up most of the forb class in the 150
Table 32. Mountain goat food habits as determined by analysis of nine rumen samples.
Percent Volume S umme r Trans i t îonal W inter P1 ants Range Range Range (n=6) (n=2) (n=l )
Grasses, sedges, rushes 71.5 61.8 73.7 Un i dent ifie d 53.5 57.7 25.3 Ag ropyron sp icatum 42.9 Elymus g 1aucus 4.0 Carex sp. 15.5 0.1 Carex geyerÎ 5.5 Carex phaeocephala 0.4 Luzula sp. 1.6 Luzula parviflora 0.5 Juncus parryi T Juncus rega1i i T
Forbs 26.1 34.7 Unident i fi ed 10.3 0.7 Achi1 lea millefoliurn 2.0 Antennari a sp. T Antennaria umbrinella 0.7 ArabÎs lyal1ii Arab Î s microphy11 a T Arn i ca sp. 0 . 1 Er igeron caesp i tosa 0 . 1 E r i geron s imp1 ex T Er Î ogonum umbe1 latum T 1 .0 Heuchera g ros su la riifo li a T Hyper i cum formosum 8.0 0.3 Pachi stima myrsintes 2.0 Penstemon e l l i p t i eus 1.4 Penstemon f 1avescens 1.8 Polemonium pul cher i um 0.1 Po1ygonum phyto iaccaefolium 0.1 Potent ilia g 1andulosa 1 .9 Potenti11 a sp. 0.1 Ranunculus sp. T Senec io t r i angularis 1.3 Xerophy11um tenax 0 .7 27.9 Woods ia scopu1ina 0.1 151
Table 32. Continued
Percent Volume Summer Trans î tional W inter Range Range Range P1 ants (n=6) (n-2) (n-1 )
Sh rubs 2.3 3.3 T Un i dent ifie d 0. 1 0.7 T Acer g 1abrum 0. 1 Amelanch i er a l ni f o li a 2.2 Ledum g 1andulosum 0.3 Phy11odoce empetri formis I Ri bes sp. 0 .3 0 .4 Rosa sp. T Rubus i daeus T S aliX sp. T SpIrea dens i f o li a 1.0 Vaccinium membranaceum 0. 1 Vacci n i um scopari um 0 .2
Coni fers 0. 1 0.3 12.3 Ab i es 1 as iocarpa T P i nus a 1bI cauli s T P i nus ponderosa 2.6 Pseudotsuga menzi es i i 0 .3 9.7
Insect larvae T
Mountain goat hair 14.0 152 transitional range samples. Rideout (1974) reported goats in Glacier
National Park and the Sapphire Mountains consumed leaves of beargrass during June. Casebeer et al. (1950) found that goats in the Red Butte area consumed 85 percent of the available beargrass on winter range.
This species was uncommon on winter ranges in the Bitterroot Mountains.
Deciduous browse was minimal in all rumen samples. Little use of conifers occurred on summer and transitional ranges but needles and stem tips from Douglas-fîr and ponderosa pine composed 12.3 percent of the winter sample. I observed frequent browsing of these conifers on w in te r ranges during a ll 3 w in te rs. Goats most often consumed leaders from large dbh Douglas-firs and some of those trees growing on or adjacent to "key areas" were high-lined. Occasionally, goats consumed entire branches, up to 18 inches (46 cm) long, of Douglas-fir and ponderosa pine, which were blown to the ground. Casebeer et a l. (1950) stated that foliage and twigs of fallen evergreen trees were preferred by goats despite the presence of standing trees. Saunders (1955),
Brandborg (1955), Geist (1971) and Chadwick (1973) observed considerable use of conifers in winter.
Guard hair and underfur of mountain goats constituted 14 percent of the winter range rumen sample. Goat hair has not previously been reported in rumen contents. Goats may ingest some hair while shedding as they occasionally nibble at molting sites. Irritations caused by insects and probably ticks also elicted nibbling and licking of pelage during spring and summer. Dr. B. W. O'Gara (pers. comm.) felt that elk hair, sometimes found in rumens of that species during spring. 153
was Ingested while grooming or relieving irritation from ticks.
I suspect goats incidentally ingest only small quantities of hair
during comfort activities. Three separate incidents indicated that
mountain goats purposely consume hair either from themselves or other
goats. An AF, observed on 16 July 1974 in Big Creek Canyon, chewed
an 8 inch (20 cm) square chunk o f h a ir from her unshed l e f t buttock
and swallowed it. On 6 April 1975» a K chewed and ingested hair from
the flank and buttocks of a smaller, bedded K. When the bedded K
rose, the larger K butted him in the rump. After the two jostled
head to rump for several seconds, the larger K again bit and ate hair
from the smaller K, this time from its dorsal ridge. Following an
exchange of butts, the small K fled along the ledge. The large K moved to the s m alle r's bedsite , pawed, and bedded there. The small K
returned 1.5 minutes later and bedded also, but at a spot providing a
poorer view. On 5 June 1975» 1 watched an AF eat hair from a 2F.
Both were bedded, then the AF rose, walked over to the 2F, and pulled
and swallowed hair from her molting left shoulder for 18 minutes. The
2F appeared uneasy at first but remained bedded. The AF rebedded at
her former bedsite.
In the latter two incidents, an apparently dominant animal
consumed hair from another goat without requite. This suggests that
pilophagy may hold some behavioral significance - perhaps as a
ritualistic display of social rank. In all three cases, not only was
hair intentionally eaten but considerable amounts were consumed. Hair
is primarily composed of schleroprotein. Since this is a highly 1 5 4
indigestible compound, it is unlikely that mountain goats could
reclaim significant amounts to satisfy physiological needs (B. W. O'Gara
pers. comm.). There are no other reports of pilophagy in mountain
goats, and its exact function in the Bitterroots remains undetermined.
Casebeer et al. (1950) reported that a rumen sample from a goat
shot on 1 7 October 1934 in Sweeney Creek of the Bitterroot Range
contained 63 percent sedge (Carex sp.), 13*7 percent wheatgrass
(Ag ropy ron sp. ) , and 2-6 percent each o f evergreen ceanothus, creeping
hoilygrape (Berberis repens), rose (Rosa sp.), and Idaho fescue (Festuca
idahoensIs). He also listed percent composition of rumen contents from
two wintei—killed goats found in Chaffin Canyon of the Bitterroots. One
contained 50 percent each grasses and mountain mahogany; the other
contained 8 0 percent mountain mahogany, 10 percent creeping hollygrape,
and 10 percent grasses. I did not find mountain mahogany on winter
ranges in the study area.
Anderson (1940), Casebeer et a l. (1950), Saunders (1955), Hibbs
et a l. ( I 9 &9 ), Brandborg (1955), and Chadwick (1973) all found grasses
and sedges comprised the bulk of winter diets of mountain goats.
Brandborg (1955), Peck (1972), and Kuck (1973b) reported heavy use of browse in winter, particularly mountain mahogany. This species accounted
fo r 42, 7 1 , and 54 percent, respectively, of the winter diet in areas
investigated during those studies. Kuck (1973b) also found 54 percent
use of mountain mahogany during spring (March-May).
Winter range investigations. Observations of feeding mountain goats and reconnaissance of w in te r ranges from January to June 1973-1975, 155 produced the following unquantified evaluation of winter food habits.
Bluebunch wheatgrass, other grasses (Koeleria cristata, Bromus marg i natus, and Poa spp.), and elk sedge (Carex geyeri) comprised the bulk of the winter diet. These species were locally eaten to within
1 inch (2 , 5 cm) of the ground on snow-free ledges during winters 1974 and 1 9 7 5 . Forbs were a relatively unimportant forage class in winter.
Evergreen forbs received more use than cured species. Forbs eaten by goats, in descending order of estimated consumption, include: creeping h ollygrape, aspidot is (Aspidotis densa) , penstemons (Penstemon s p p .), alumroot (Heuchera cylindrica), gland cinquefoil (Potent il la glandulosa), yarrow (Achillea millefolium), stonecrop (Sedum stenopetalum), Douglas knotweed (Polygonum douglas i i ) , cudweed sagewort (Artemes ia 1udoviciana) , chickweed (Ceras t i um arvense), sulphur buckwheat (Eriogonum umbel latum), pussytoes (Antennari a spp.), dwarf mountain fleabane (Er i geron caesp i tosus) , and stickseed (Hackella cinerea). As ephemeral forbs and new growth on perennials appeared in May and June, a greater diversity and volume of forbs were consumed by goats. Chadwick (1973) listed 4 species of forbs taken by goats from feeding sites during April, 27 species in May, and 54 in June.
Results o f forage biomass measurements on the Fred Burr w in te r range are presented in Tables 33 and 34. These measurements included only herbaceous species, exclusive of lichens; mosses and selagînella
(Selag i nel1 a wal1 ace i and densa) were simply recorded as present or absent from each sample plot. The sampling period (14 November to
10 December 1974) coincided with the arrival of goats on winter range. Table 33* Productivity of important herbaceous forage plants of mountain goats measured on 137 ranked-set plots during late fa ll 1974 on Fred Burr winter range.
Green Weight (g) Oven-■Dry Weight (g) Max. Ibs/a Ibs/a Species Frequency Plot Total Mean (kg/ha) Total Mean (kg/ha)
Agropyron spicatum 0.78 162 2,788 20.4 204 ( 228 ) 1,930 14.1 141 (158) Bromus marginatus 0.42 56 733 5.4 54 ( 60) 384 2.8 28 ( 31) Koeleria cristata 0.53 50 554 4.0 40 ( 45) 322 2.3 23 ( 26) Poa spp. 0.20 11 65 0.5 5 ( 6) 42 0.3 3 ( 3) Other grasses 0.11 61 121 0.9 9 ( 10) 63 0.5 5 ( 6) Carex geyeri 0.50 208 1,847 13.5 135 (151) 975 7.1 71 ( 80) Carex lasiocarpa 0.06 77 170 1.2 12 ( 13) 101 0.7 7 ( 8) Antennaria spp. 0.05 18 69 0.5 5 ( 6) 52 0.4 4 ( 4) Arenaria conges ta 0.23 17 34 0.2 2 ( 2) 26 0.2 2 ( 2) Aspidotis densa 0.14 126 402 2.9 29 ( 32) 162 1.2 12 ( 13) Heuchera cylindrica 0.04 16 39 0.3 3 ( 3) 28 0.2 2 ( 2) Penstemon spp. 0.03 5 11 0.1 1 ( 1) 8 0.1 1 ( 1) Polygonum douglas i i 0.29 19 103 0.8 8 ( 9) 82 0.6 6 ( 7) Berberis repens 0.15 24 198 1.9 19 ( 21) 94 0.7 7 ( 8)
TOTAL 7,134 52.6 526 (589) 4,269 31.2 312 (349)
vn ON Table 34. Productivity of additional herbaceous forage, not listed in Table 33, measured on 137 ranked-set plots during late fa ll 1974 on Fred Burr winter range.
Occurrence by Class® Mean Green Green Weight Total wt (g)/I37 Ibs/a Species Frequency Occurrence Trace 1 2 3 4 5 Sample Plots (kg/ha)
Achi1 lea millefolium .39 53 5 25 16 5 2 2.7 27 30) Artemesla 1udovici ana .09 12 - 2 3 5 2 - 1.4 14 16) Epilobium spp. .09 13 5 8 - - - 0.2 2 2) Eriogonum umbel latum .23 31 1 12 8 5 4 1 3.0 30 6) Leptotaenia m ultifida .26 36 5 16 10 4 - 1 1.9 19 21) Potent ilia glandulosa .18 24 1 11 8 4 - - 1.2 12 13) Sedum stenopetalum .36 49 11 21 11 6 - - 1.9 19 21) S1lene douglasii .05 7 3 3 1 - - - 0.1 I 1) Solidago missouriensis .09 13 1 4 1 4 3 - 1.5 15 17) Other evergreen forbs .07 9 3 5 1 - - - 0.2 2 2) Other non-evergreen forbs .44 60 9 30 9 11 1 - 2.9 29 32) Mosses .55 76 ------Selaginella spp. .53 72 ------
Average^ .20 28 4.0 12.5 6.2 4.0 1. 1 0.2
Average Green Weight 1 bs/a 0.1 3.0 4.0 5.8 3.3 0.9 17.1 171 (kg/ha) (T) (3.4)(4.5)(6.5)(3.7)(I.O) (19.2) (192)
^Classes: Trace<0.5g; 1= l-5g; 2 = 6-lOg; 3 = ll-25g; 4 = 26-50g; 5 = 51-75g.
^Exclusive of mosses and Selaginella spp. 158
All grasses, two sedges, and nine forbs contributed 526 pounds/acre
( 5 8 9 kg/ha) to the total herbaceous biomass. The remaining forb species added another 171 pounds/acre (192 kg/ha) for a total of 697 pounds/acre
( 7 8 1 kg/ha). Bluebunch wheatgrass and elk sedge provided 48.6 percent of herbaceous biomass. Sulphur buckwheat, aspidotis, and yarrow were the most plentiful forbs. Cliffs with prominent ledges and parkland colluvial slopes, on which 6 O-8 O percent of all goat sightings occurred in the study area from November 1974 to A pril 1975 (Table 28 ), characterized the te rr a in of the sample area (Fig. 6 ). Conceding the limitations of sampling forage productivity in mountainous terrain,
6 9 7 pounds/acre (781 kg/ha) probably is a representative measurement of production on these two te rr a in types in Fred Burr Canyon. However, this figure certainly overestimates herbaceous biomass throughout winter range since other terrain types were less productive. Chadwick (1973) measured herbaceous productivity on primary winter range in Little
Creek drainage of the Swan Range. That range was located on a windswept ridgetop and supported 377 pounds/acre (422 kg/ha) of forage (air-dry weight) during fall.
I frequently observed goats nibbling follose (Umb Î 1i cari a spp.) and fruticose (Cladonia spp.) lichens from rock during winter and spring. Selaginella and mosses were also stripped from rock. Goats seemed to prefer lichens and mosses when moistened by rain or melt w ater. They spent considerable time removing lichens from the underside of rock ledges where moisture was retained by the plants. Chadwick (1973) found 1 3 . 8 percent use of lichens, mosses, and ferns in the Swan Range, 159 and Brandborg (1955) recorded goats spending 24 percent of their
feeding time eating follose lichens.
Browse probably contributed 20 to 30 percent to the dietary
intake of mountain goats in Fred Burr Canyon during winter and early spring. Browse became particularly popular during periods of deep or crusted snow. Although the rumen contents collected on winter range
indicated conifers as favorite browse plants, my observations revealed
they were less important than deciduous and evergreen shrubs. At least
22 species of tall shrubs grow on the Fred Burr winter range; only eight of those received significant use by mountain goats. During
May 1975» I classified leader utilization of some 5,400 individual plants of those eight species (Table 35) on five “key areas" of the Fred Burr winter range (Fig. 27). Since several mule deer (probably less than six) were the only other large herbivore which occupied the winter
range, differential shrub use was interpreted as species preference by mountain goats. Two species o f curran t, Ribes cereum and vi scosIss imum, were classified together as RIbes spp., and comprised 47.1 percent of all shrubs classified. Serviceberry (Amelanchier alnifolia) was the most heavily used species throughout five sample areas with 6 9 percent of plants heavily hedged, followed by mountain maple (Acer glabrum) , evergreen ceanothus, and chokecherry (Prunus v irg in ia n a ). Some marked differences prevailed from east (sample area A) to west (sample area E) on the winter range. 1) More plants, 36 percent, of all eight species fell into the heavily used class on eastern sample areas (A, B, and C) compared w ith western areas (18.3 percent). The prop ortionately greater lass ification of eight shrub species from five "key areas" on the Fred Burr winter range according to past use.
Amelanchi er Prunus Ceanothus Acer Ribes Sal iX Holodi sous Ph i 1adelphus zation a ln ifo lia vi rginiana velutinus glabrum spp. spp. discolor lewisii Total Mean ss No. % No. % No. % No. % No. % No. % No. % No. % No. %
48 6 28 19 31 7 4 12 1145 50 1 14 35 57 356 56 1654 37.4 um 140 19 50 35 90 19 9 27 553 24 12 24 15 24 136 21 1005 22.7 544 72 58 40 269 57 19 58 532 23 28 55 12 19 131 21 1593 36.0 dent 23 3 9 6 69 15 1 3 54 2 4 8 - - 10 2 170 3.8 AL 755 17.1 145 3.3 459 10.4 33 0.7 2284 51.7 51 1.2 62 1.4 633 14.3 4422 81.7*
26 32 25 29 90 46 5 29 151 57 88 55 76 66 39 58 500 50.4 um 18 22 29 34 49 25 7 41 73 27 38 24 28 24 17 25 259 26.) 37 45 27 32 38 19 5 29 32 12 26 16 8 7 8 12 181 18.3 dent 1 1 4 5 20 10 - - 11 4 9 6 4 3 3 5 52 5.2 AL 82 8.2 85 8.6 197 19.9 17 1.7 267 26.9 161 16.2 116 11.7 67 6.8 992 18 .3^
74 9 53 23 121 18 9 18 1296 51 95 45 111 62 395 56 2154 39.8 um 158 19 79 34 139 21 16 32 626 24 50 24 43 24 153 22 1264 23.3 581 69 85 37 307 47 24 48 564 22 54 25 20 11 139 20 1774 32.8 dent 24 3 13 6 89 14 1 2 65 3 13 6 k 2 13 2 222 4.1 AL 837 15.5 230 4.2 656 12.1 50 0.9 2551 47.1 212 3.9 178 3.3 700 12.9 5414 100.0
'ortancef 10.7 1.6 5.7 0. 4 101.4 0. 9 0.4 2.6
all plants classified from sample areas A,B, and C.
all plants classified from sample areas D and E. ON o wily browsed X percent abundance/100. Fig. 2 7 . Locations of five "key areas" on the Fred Burr winter range (A - E) on which numbers of eight browse species were classified according to past use by mountain goats «600
V
I mile
7000 Ftn
1 kilometer
CONTOUR INTERVAL 40 FEET DATUM IS MEAN SEA LEVEL 162 number of goats observed, during censuses, on the eastern 2 miles
(3-2 km) of winter range probably accounts for this disparity.
2) Serviceberry, currants, and mock orange (Phi1ade1phus lew isii) were
relatively twice as abundant on the drier and lower eastern sample areas, as on the western areas.
Although less abundant than serviceberry or currants, evergreen ceanothus plants provide abundant winter forage since they remain green. Overwinter leader use of 185 evergreen ceanothus plants, tagged the previous fall and examined during May 1975, provided information on annual consumption of this plant by mountain goats. Of 7,520 recorded leaders, 6-6 percent were browsed and 1.7 percent were w in te r -k ille d .
The tagged shrubs grew on a variety of terrain types and exposures at elevations commonly frequented by goats on that portion of the Fred Burr winter range (Fig. 6). Many plants were s till snow covered when checked on 14 May. Table 35 illu s tr a te s that this species was hedged fa r more on the eastern browse sampling areas. Deep snow reduces the availability o f th is browse species on western portions o f w inter ranges in the
B itte rro o t canyons more d r a s tic a lly than the other seven shrubs because of: 1) its prostrate growth form; and 2) its scarcity on steep, windswept m icrosites.
The importance of each plan t species to mountain goats depends upon availability (or quantity), palatabi1ity, and nutritive value. For shrubs, multiplying the percentage of heavily hedged plants by the relative abundance of a species furnishes a number by which species importance can be ranked on the criteria of availability and palatabi1ity. 1 6 3
Table 35 illustrates that serviceberry, currants, and evergreen ceanothus were most important on winter range. Isdahl (1976) analyzed crude protein content of 15 plant species growing on the Fred Burr winter range. Sullivan (1962) states that high crude protein content is generally indicative of high plant nutritional quality. Dietz (1965) regarded protein as essential for body maintenance, growth, reproduction, lactation, and effective digestion and metabolism of carbohydrates and fats in the rumen. Cowan (1970) stated that high protein forages were usually succulent and palatable and their non-protein (carbohydrates) constituents were highly digestible. The more protein, the healthier is the rumen microbial population and greater its capacity to digest more fibrous foods. Dietz (1965) and Cook and Harris (1950) observed that with advancing maturity: 1) protein and mineral content of plants decreased; and 2) crude fat, fiber, and nitrogen-free extract increased.
Therefore, adequate protein levels became particularly important on goat winter ranges where the final stages of plant phonological maturity were reached.
The National Academy of Sciences-National Research Council
(Anon. 1957) recommended 7 to 11 percent protein in the diet of domestic sheep. Dietz (1965) gave 6 to 7 percent protein as the minimal level for winter maintenance in deer. Isdahl's (1976) analyses showed an overall protein level of 7.4 percent in current annual growth of winter forage during March (Table 36). Four of the five species exhibiting the highest protein levels remained green in winter. Protein levels exceeded
7 percent in only three o f nine browse species. Bluebunch wheatgrass. 1 6 4
Table 3 6 . Protein content of winter forage plants in Fred Burr Canyon, Montana, Rattlesnake drainage, Montana, and the Anshola watershed, British Columbia.
Col 1ect i on Percent Study Spec i es Date Protein
Isdahl (1 9 7 6 ) Aspidotis densa March 1975 12.2 1 1 M Berberis repens 1 0 . 3 1 1 Prunus v irg in ia n a 11 10.0 11 1 1 4 Mosses 9 . 6 11 1 1 Ceanothus velutinus 9 . 2 1 1 II 2 Lichens 8 . 3 1 1 Ribes spp. 11 8.1 1 1 11 S a lix spp. 6 . 7 1 1 11 Carex geyeri 6 . 3 1 1 Acer glabrum 11 6.1 1 1 Amelanchier alnifolia 11 6.0 1 1 Pseudotsuga menziesii 11 6.0 1 1 11 Philadelphus lewisii 5 . 6 1 1 11 Holodiscus discolor 4 . 3 1 1 11 Agropyron spicatum 2 . 5
1 1 Average^ 8 . 3 Average^ 7*4
Knoche Berberis repens March 1 9 6 8 9 . 3 t ( Prunus v irg in ia n a February 1 9 6 8 8.2 11 11 Ceanothus velutinus 8 . 9 11 11 Amelanchier alnifolia 5 . 8 11 Pseudotsuga menziesii November I 9 6 8 6.4
11 Average 7-7
Demarch i Agrypopyron spicatum March 1 9 6 8 2.8 from Isdahl (1976)
^Average percent protein of the same five species analyzed by Knoche ( 1968 ) bAverage percent protein for all species. 165 the only cured plant sampled, ranked last in protein content. Knoche
( 1 9 6 8 ) studied range ecology of the highly productive Rattlesnake mule deer herd north of Missoula, Montana, and found crude protein
levels in range plants lowest during winter (January to March). For
five plant species analyzed in both studies, isdahl (1976) reported an
average protein percentage of 8 . 3 in Fred Burr Canyon compared to
7 . 7 in the Rattlesnake drainage (Table 36). On the basis of crude fat and p ro tein content, Demarchi ( I 9 6 8 ) concluded that bluebunch wheatgrass was the most nutritious grass in the fall to spring diet of the Anshola
bighorn sheep herd. Crude fat provides 2.25 times more energy than carbohydrates and proteins (Dietz 1965). During winter, Knoche (1968)
recorded the highest content of crude fat and protein in evergreen ceanothus. Crude fat levels in forage plants in the Bitterroot
Mountains are unknown.
Isdahl (1 9 7 6 ) concluded the following from her study: 1) No significant differences in protein percentages existed between the
high, moderate, and low shrub classes used by goats. This supports
D ie tz' ( 1 9 6 8 ) conclusion that heavy browsing of shrubs by big game animals probably does not affect their nutritive content. Perennial browsing of plants on "key areas" of goat winter range did not reduce their nutritional value, although it appeared to alter growth form and productivity. 2) One-year-old leader growth of eight shrub species and one conifer averaged 5-4 percent protein compared to 6.5 percent
for current annual growth. This implies that old growth provides
less protein per unit weight than current growth does. Mountain goats 166 occasionally browsed fa r back into past years' growth on shrubs and
Douglas-fir. On 4 April 1975» an AF approached a 7 foot (2 m) serviceberry bush which was stripped of reachable leaders. She mouthed a main stem, 1 inch (2 .5 cm) dbh, b itin g and tw istin g u n til it finally broke. Then she commenced to eat all the lateral branches and most of the 4 foot (1.2 m) length of main stem. Such browsing techniques, while yielding large amounts of food, fill the rumen with relatively poor quality vegetation.
Feeding techniques. Ground surveys of winter ranges revealed that locations of prime feeding areas depended largely on snow depths
In particular, browse as well as herbaceous plants growing near the edges or on windward sides of ledges received heaviest use. Goats expended less energy to obtain food from such snow-free sites.
When foraging on fibrous grasses or forbs, goats gathered mouthfuls of leaves and culms or stems, then tugged th e ir heads to one side to sever the material. Goats severed shrub and conifer leaders positioned across incisiform teeth with a quick jerk of the head. Browsing often required repeated tugging if leaders did not cross incisiform teeth. Goats also scraped lichens and mosses from rocks w ith in ciso rs, although they sometimes removed them w ith th e ir tongues. Many adult goats, killed by hunters, were missing one or more front teeth and others were often loose. A 12-yeai—old female had only one in cisifo rm tooth; and an old AM had none. P a rtia l or complete loss of incisi forms may reduce feeding efficiency by consuming more time and energy during grazing and browsing and 167
Impairing procurement of such high protein plants as lichens and mosses.
Reproduct ion
Mat i ng. AMs were observed 34 times on transitional and winter ranges in Fred Burr Canyon between S November and 19 December of 1973 and 1974 . Of the 34 observations, 22 involved AFs, and during 20 of the 22, AMs actively courted females. Lone males traveled extensively during November and December, presumably in search of receptive females. One AM apparently did not participate in the rut in 1974.
This individual, distinguished by the absence of swollen occipital glands, was observed from 27 November to 3 December on tra n s itio n a l range west o f a ll other goats. On 8 December, 1 encountered a set o f AM tracks (fro n t hoof measurements were 2.75 x 2.5 inches - 7*0 x
6 .4 cm) which descended the south-facing canyon wall from the v ic in ity where the AM lacking visible occipital glands was repeatedly seen.
I followed the tracks across Fred Burr Creek and 8 OO feet (244 m) up the no rth -facin g canyon w all through 2 fe et (O . 6 m) o f snow. They continued ups lope through coniferous forest from there. It is unlikely that this large male was searching for AFs since he did not seek their company on the Fred Burr winter range.
Between 9 November and 19 December, 46 percent of the sexually mature females (AFs and 2Fs) observed in 1973 and 86 percent in 1974 were attended by AMs. Fig. 11 shows that the proportion of observed mixed (AM-AF) groups was highest during November, December, and
January. Courtship activity culminated about 1 December in Fred Burr 168
Canyon. On that date in 197^» three copulations were performed between an AM and AF Alpha. The second copulation ended after 7 seconds when the AM's bulk flattened Alpha, leaving her forequarters dangling precariously over a sheer drop. A backward hornswipe prompted the AM to dismount and she regained the ledge. This pair and Alpha's kid of the previous spring remained together the following
2 days and the AM continued courting her. Chadwick (1973) also
reported that rutting males remained with the same female or group for periods up to 3 days. On 1 December 1973, 3 AMs, one quite small and
the other two large, followed an apparently estrous AF. Repeated agonistic interactions between the males clearly established their
respective hierarchical status. The dominant male mounted the AF on
four occasions during 55 minutes of observation. Wind-driven snow hampered observation and it was unclear whether copulation took place.
Geist (1964), Holroyd (1987), and Chadwick (1973) reported the last
2 weeks of November as the peak of the rut in B ritis h Columbia and
Montana. DeBock (1970) regarded 1 December as the peak date of the
rut in Kootenay National Park, and Brandborg (1955) recorded a mating on 8 December.
Rutting pits, described by Geist (1964), were numerous on broad c liff ledges and colluvial slopes frequented by AMs during the rut in
Fred Burr Canyon. Thirteen ru ttin g p its , averaging 30 x 36 inches
( 7 6 X 91 cm) in s iz e , were located on 2 December 1973 along a 500 yard
(457 m) section of winter range above Fred Burr Reservoir. Geist (1964) and Chadwick (1973) gave average measurements of 12 x 18 inches 169
(30 X 64 cm) and 30 x 44 inches (76 x 112 cm), respectively, for
rutting pits. All instances of rutting pit digging were performed by
AMs or 2Ms. However, on 1 December 1974, AF Alpha entered a
rutting pit, dug by her attendant AM, and pawed soil over her flanks
and belly. Geist (1964) regarded rutting pit digging and other
ritualistic behavior reversals by AFs as "unusual."
Ki dding. During la te May, AFs sought rugged portions o f w inter
range on which to bear their young. During three kidding periods
( 1 9 7 3 - 1 9 7 5 ), a ll observations o f neonates in Fred Burr Canyon, p rio r
to 10 June, were on a 1.1 mile (1.8 km) long area located centrally
on the winter range. Offspring were first seen on 28 May during all
3 years and most were probably born within a 10 day period. During
the last week of May 1975, on a 6-day back-pack trip across the Fred
Burr winter range, I recorded three new kids with six AFs. A
subsequent 6-day survey, beginning 4 June 1975, yielded three Ks with
seven d iffe r e n t AFs. Considering 1 December and 1 June as the
respective average dates of mating and parturition, the gestation
period for goats in the Bitterroot Mountains is 182 days. This agrees with DeBock's (1970) calculation of 18 3 days in Kootenay National Park
and Seton's (1953) record of 178 days for captive goats in the Bronx
Zoo.
Studies in Montana (Casebeer et al. 1950, Brandborg 1955,
Chadwick 1973 and 1974, and Rideout 1974), Washington (Anderson 1940),
Idaho (Brandborg 1955, Kuck 1973a) and British Columbia (Holroyd 1967)
indicated that twinning was uncommon in native goat populations. 1 7 0
Twins comprised approximately 33 percent of offspring in introduced populations in Montana (Lentfer 1955) and Colorado (Hibbs et al. I 9 6 9 ).
Lentfer (1955) recorded three sets of triplets during 1 year in a
rapidly expanding population; there was no evidence of twinning in the
Bitterroot study area.
Chadwick (1973) noted a post-partum period of isolation lasting
8 to 18 days fo r nannies and young in the Swan Range o f Montana.
Post-partum activities of an AF in Fred Burr Canyon were quite d iffe r e n t. From 1510 to 1640 on 28 May 1975» an AF fed in te rm itte n tly as she traversed a 0 . 2 5 mile (0.4 km) portion of the kidding grounds.
She bedded at 1629 for 11 minutes then rose and disappeared behind a small outcrop. At 1700, I reached a vantage point and observed her suckling an infant in a broad, sparsely timbered couloir. Both were standing and she licked the amniotic fluids from her wobbly offspring as it nursed for 3 minutes. At 1703, the nanny began feeding slowly down the couloir, the K following close behind. Periodic nosing and grooming of her offspring interrupted the nanny's feeding during the next hour. At I 8 IO, she ascended an outcrop about 35 yards
( 3 2 m) below the birthsite. With some difficulty, the K joined her.
Both bedded w ith the K tucked against its mother's u p h ill side.
The K slept and intermittently nursed until dark. At 717 the next morning, the AF and K were feeding with another AF and a Y in the couloir near the birthsite. They continued traveling upslope across siiderock and disappeared around a c liff wall about 735. The nanny and K were relocated at 841 bedded on a boulder in the shade of the 171 wall approximately 700 feet (213 m) of elevation above their bedsite of the previous evening. Both rose at 855, traveled west across the sliderock, and disappeared from view about 915. In all, their morning's travel covered about 400 yards (3^6 m). This and other observations, during late May and early June 1974 and 1975, indicated that neonates were highly precocious and capable of following their mothers through rugged te rra in soon a fte r b irth .
Appraisal of reproductive success. The number of Ks observed on the Fred Burr winter range during successive winters declined from
9 in 1973 to 7 in 1974 and 4 in 1975. Numbers o f AFs remained constant. Only three of seven AFs observed during spring 1975 produced Ks; two other AFs were not seen.
Several factors influence reproductive success in ruminant populations: 1) heredity, 2) nutrition, and 3) other environmental factors (Miller et al. 1942). Since heredity has little effect on year-to-year fluctuations in reproduction, only the latter two factors seem worth considering. Many investigations of wild and domestic
North American ruminants have correlated poor productivity and/or survival of young with dietary nutritional deficiencies. Simil'ar studies of mountain goats are lacking.
In the following review, the natality process for goats in the study area is discussed relative to studies of other ruminant species.
Swenson (1973) listed four stages of the natality process:
1) ovulation to fertilization;
2) fertilization to implantation; 172
3) implantation to parturition; and
4) postpartum survival.
Losses during any stage suppress reproductive success. Julander et a l. ( 1 9 6 1 ) found higher ovulation and fetal rates among mule deer does summering on range o f high n u tritio n a l q u a lity than those on poor range. Ransom (I 9 6 7 ) related fall nutrition to ovulation rates of white-tailed deer in Manitoba. Quality of summer and transitional ranges in the Bitterroots was not investigated. However, preferred herbaceous forage was abundant throughout the study area during summer. Forage also abounded on tra n s itio n a l ranges during f a l l .
High-elevation forage is nutritionally superior, particularly in protein content, to low-elevation forage (Johnston et al. 1968,
Hebert 1973» and Stelfox 1975). Quality or availability of summer-fall forage during 1973 and 1974 probably did not reduce ovulation or fetal rates of mountain goats. The possibility that some AFs were not serviced also seems remote since goats are polygamous and AM:AF ratios ranged from 0.50:1 to 0.67:1 in Fred Burr Canyon during the study.
Studies of domestic sheep (Moustgaard 1959» Thompson and
Thompson 1948), white-tailed deer (Cheatum and Severinghaus 1950,
Verme 1 9 6 2 and 1963» Murphy and Coates 1966, Ransom I 9 6 7 )» elk
(Thorne 1970» and bighorn sheep (Hebert 1973) demonstrated that a high plane of nutrition is necessary during pregnancy if gravid females are to bring large, viable offspring to term. Verme (I 9 6 3 ) showed that at about 1 3 3 days' gestation, inadequate nutrition begins to retard fetal development. He found that undernourished white-tailed 173
deer does produced sm aller fawns w ith poor chances of s u rv iv a l.
Thorne (1971) studied eight undernourished, captive cow elk which
lost 10 percent or more of their body weight prior to parturition. Of
these, three either aborted or resorbed fetuses; offspring of four
survived less than 1 month; at 4 weeks the fifth calf weighed only
40 percent as much as calves born to cows not experiencing
pre-parturition weight loss. Thorne (1971) also found survival to 1 month of age for large calves far exceeded survival of small ones.
Verme (1962) noted some fetal deaths and stillbirths among white
tailed does on a low to moderate dietary plane, although **. . . the major cause of death was postnatal nutritive failure." More than a
th ird o f the fawns born to those does died w ith in 48 hours a fte r b i r t h .
D ietz ( 1 9 6 5 ) regarded protein as essential for reproduction and lactation. Murphy and Coates (I 9 6 6 ) related high postnatal
losses among white-tailed deer to percent protein in the diet.
Postpartum fawn mortality resulted from starvation due to delayed milk production. The authors felt lactation placed an even greater stress on does than did pregnancy. Verme (1962) also emphasized the importance of proper milk production and ability of offspring to suckle for fawn survival. On the Fred Burr winter range, crude protein content of
15 food plants used by mountain goats averaged 7*4 percent during late
March when vegetation was dormant (Isdahl 1976). This level was
reported adequate for deer and domestic sheep and, in the absence of specific studies, seems reasonably applicable to mountain goats. 174
Protein, phosphorous, and carotene levels rise in forage with the
commencement o f growth in spring (Cook and Harris 1950, Knoche 1968),
and total digestibility and palatabîlîty is higher for green
vegetation (Cook and Harris 1950). During 1974 and 1975» plant
phenology was delayed approximately 1 to 2 weeks and 4 weeks,
respectively, in the Bitterroot Mountains. Consequently, gravid
females had to subsist on dormant forage during late pregnancy.
Stelfox (1975) found that bighorn ewes lost 18 to 22 percent of their
body weights during severe winters in which 38 and 3 2 percent of winter
ranges were unavailable due to chest-deep snow, and observed that
bighorns, like mountain goats, avoided such snow. He postulated that
following severe winters when ewes were in poor condition, the
rapidity of spring "green-up" largely determined reproductive success.
Reproductive success was probably low in Fred Burr Canyon during 1974 and 1975 because of: high energy expenditures for feeding and travel; overuse, by AFs, of some "key areas'' which led to consumption of poor quality forage during late gestation; and delayed appearance of green forage in spring. All three were directly related to deep and persistent snow cover on the winter range. Whether the losses were
in-utero or postpartum is conjecture. Evidence of abortions or neonatal death were not discovered nor were they likely to be found on rugged goat winter ranges. Vaughan (1975) regarded alternate year production by females as responsible for the tenuous status of the Wallowa goat population. Although this mechanism was apparently not operating during 1972 and 1973 in Fred Burr Canyon, i t may have a ffected 175 p ro d u c tiv ity in 1974 and 1975* The AF, radio-equipped in A pril 1974, was accompanied by a K that winter and spring. A K was not observed with her the following summer, fa ll, or winter. During sequential prolonged winters, a year's recovery may be necessary to restore a
female's energy reserves for successful reproduction.
If reproductive success in Fred Burr Canyon and throughout the
B itte rro o t Range depends upon annual c lim a tic conditions, then marked
fluctuations in the annual increment and population size are a
recurrent natural phenomenon. CHAPTER V
MANAGEMENT RECOMMENDATIONS
Hunter Harvest
Casebeer et al. (1950) reported a decline of the goat population in the Bitterroot Mountains from an estimated 1,000 animals in 1 9 2 5 to about 315 in 1947. The population in what is now Hunting
District 240 was conservatively estimated at 265. They stated that the goat population . . suffered a heavy natural loss regardless of the hunting pressure. The added hunting pressure aided in diminishing the base herd fo r the a rea ." The hunting season was subsequently closed from 1948 to 1954 to allow a recovery of the population. Hunter harvest during the 1925 to 1947 period averaged 2 3 goats annually for the Bitterroot Unit (Districts 240 and 250). Since 1954, hunter harvests averaged 37 goats annually in District 240, Natural mortality from 1 9 7 3 to 1 9 7 5 in Fred Burr Canyon was at least equal to hunter kill
For a species with low reproductive and high natural mortality rates, such as the mountain goat, hunting must be carefully regulated to insure that no more than a harvestable surplus is taken by hunters.
Hunters tend to kill adult animals, the reproductive segment of the population. Natural mortality is greatest among Ks and subadults.
Consequently, the two tend to be additive in effect. It appears that the goat population cannot sustain the present rate of harvest.
Following 2 severe winters which produced high natural losses and
176 177 depressed reproductive success, a recovery period is necessary. I
recommend a reduction in the number of permits for District 240 until census data in d icate an upward trend in population numbers.
Census i ng
The status of the goat population in District 240 should be closely monitored in the fu tu re . Annual censuses of each canyon during winter and spring offer the best method for collecting needed biological data. Successful management of goat populations entails maintaining viable numbers of animals in constituent herds. During summer in the Bitterroots, goats from various herds disperse and
intermingle across continuous summer ranges. Summer censuses provide no indication of the status of individual herds, although they do provide estimates of gross productivity of viable offspring and population numbers. During winter, goats aggregate on respective herd winter ranges and are more easily counted. Wintei—spring censuses
reveal net productivity, a better measure of the annual rate of increase than gross productivity, and herd numbers following hunting mortalities.
Trends in wintei—spring censuses can show specific herds which may be suffering from exceptionally high mortality or low reproduction and require relief from hunting pressure.
Without question, aerial surveys are more economical, time-saving, and suited to censusing vast and inaccessible regions. Such surveys provide information on herd or population numbers and distributional data. Aerial surveys have consequently proved successful management tools in Colorado (Hibbs et a l. 1969), Oregon (Vaughan 1975), Alaska 1 7 8
(K lein 1953), and parts of Idaho and Montana (Kuck 1973a and Lentfer
1 9 5 5 ). However, the accuracy of aerial censuses for establishing herd trends in the B itte rro o t Mountains in Montana remains to be v e rifie d .
Aerial trend counts fluctuated considerably since 19^8 for District
2h0 and individual drainages (Fig. 10 and Table 16). The technique neither provides reasons for such fluctuations, nor any assurance that the fluctuations are real. Two or more surveys, conducted over the same area within a few days or weeks of each other, might reduce error. Surveys should be conducted in late April or May. Goats are most visible from the air soon after most snow disappears from lower south-facing canyon walls and are frequenting "green-up" areas on warm, snow-free s ite s . Censuses should be conducted during morning or late afternoon while goats are active.
Ground censuses proved the most accurate method of censusing mountain goats in the Bitterroot Mountains. Mean ground censuses yielded about twice as many goats on winter ranges as did aerial censuses. Ground censusing w ith a v a ria b le power spotting scope enabled classification of each goat thus providing data on population structure, annual survivorship by class, reproductive potential of herds (number o f AFs plus 2 F s ), and a method (cohort-comp1 et ion) o f improving population estimates with repeated censusing. Data on h a b ita t s e le c tio n , behavior, food h abits, d a ily movements, and w in te r range fidelity of recognizable animals were also readily obtained during ground censuses. One drainage was censused per day. 1 7 9
Time and manpower preclude annual censusing o f each herd in
D is t r ic t 240. Therefore, several ground censuses during w in ter or spring of each of five or six representative drainages would furnish a wealth of information on those herds. This information could reasonably be extrapolated to the entire population. Another possibility is to test the accuracy of aerial trend counts by comparing them with simultaneous ground censuses of known-size herds during successive years. A correction factor could then be applied to calculate herd and population trends in D is tr ic t 240. Spot ground checks in each drainage would provide a sample of herd composition and productivity for extrapolation to the entire herd with the correction factor.
Land Development
Wise management of mountain goats involves protection of habitat as well as careful regulation of hunting. In some locations, protection of goat habitat from conflicts with man is assured due to inclusion in wilderness or primitive areas. In the Bitterroot Mountains, this is only partially the case. All of the Fred Burr and Blodgett winter ranges, and part of winter ranges in other canyons, lie outside the Selway-Bitterroot Wilderness on U.S.F.S. land. Carrying capacities of winter ranges limit the size of each herd and thus the total Bitterroot population. In the past, an unroaded buffer zone existed adjacent to goat h a b ita t in a ll the B itte rro o t canyons u n til
of harvestable timber stands on the foothills and Bitterroot
Valley floor prompted logging the east flank of the Bitterroot Range.
C urrently cut-over acreage and roads e x is t above goat range in Sweeney, 180
Sweathouse, and Bear canyons on the S te ven sville Ranger D is tr ic t.
During the next 20 years, roadless area on the Bitterroot North
Planning Unit will decline 26 percent as a result of logging.
According to the Bitterroot North Plan (Anon. 1974c), rîdgetops adjacent to goat winter ranges in Bass, Bear, Fred Burr, M ill, and
Blodgett canyons w ill be logged and roaded. Logging per se is not the problem; providing access to critical portions of goat winter range is.
The General Management Guidance section (page 44) of the
Bitterroot North Plan recognizes the incompatibility of mountain goat habitat and roads and states roads will not be built ". . . on or
immediately adjacent to . . ." goat habitat. But ". . . immediately adjacent to . . w hile undefined, implies that roads may be constructed to the edge of known habitat. To maintain current numbers of mountain goats in each canyon, I feel it is necessary to exclude
roads from a buffer zone established next to known goat winter ranges.
Current plans call for timber harvesting, by conventional systems, on Sections 17 and 18 of eastern Fred Burr Canyon during
1978 (Figs. 4, 5, and 7). The south-facing cliffs and a contiguous strip of ridgetop in Sections 17 and 18 provide habitat for goats from
November (including part of the hunting season) through early June and should be protected from road access. Four to nine goats use this area each winter. More important than absolute numbers, nannies and
Ks are the primary occupants of this portion of the winter range.
Successful reproduction and survival of kids, which experience the highest natural mortality rate of any age group, is essential to herd 181 maintenance. Cliffs in Sections 17 and 18 are preferred areas of the winter range because of steep slopes, excellent ledge development, and their location at the eastern end of the canyon. These factors produce shallow w in te r snow depths (compared w ith western portions o f the winter range), good escape terrain, and high forage production.
Since AFs are s o c ia lly dominant in the herd, they are able to occupy preferred or "key areas" on w in te r range. Such a system promotes
K survival because food is re a d ily found and eaten, travel expends l i t t l e energy, and escape from predators is enhanced when snow depths are minimal and animals maintain energy reserves for these activities.
The herd b e n e fits , also, since AFs spending w in te r in optimum h a b ita t are less apt to abort fetuses or produce weak offspring.
After mining and logging provided access to goat habitat along the Salmon River in Idaho (Brandborg 1955)» portions of the Swan Range in Montana (Chadwick 1973), and across parts of Alberta (William K.
Hall, pers. comm.), goat populations either declined or disappeared.
I f road construction in Fred Burr and other canyons provides humans - whether i t be m o torcyclists, snowmobl1e r s , photographers, hunters, or others - easy access to the goat cliffs, the following may ensue:
1) In the short run, hunters will kill one or two more goats
in Fred Burr Canyon each year. The goats killed will
probably be females. In addition, human harassment may
cause goats to temporarily flee to, and crowd, western
portions of winter range. Data presented in Chapter I I
show that the Bitterroot Valley is experiencing a 1 8 2
population "boom". Residents and tourists alike are taking
to the mountains in ever increasing numbers for recreation.
Due to their location, accessibility, and scenic appeal, the
Bitterroot Mountains are already a popular retreat for many
recreationists. Reports from local residents indicate goats
currently receive some harassment on winter ranges from dogs,
snowmobiles, and people chasing them or shooting small
caliber firearms at them. Whether intentional or not, humans
place an additional stress on a wilderness species such as the
mountain goat. Such added stress is particularly inadvisable
under winter-spring conditions.
2) In the long run, goats (mainly AFs) may change th e ir
distributional patterns on winter ranges. Over a period of
years, or decades, they may learn to avoid areas frequented
by humans and thus use eastern portions of winter ranges
less, thereby reducing carrying capacities of winter ranges.
Or, if goats do not change their distributional patterns,
while hunters (or poachers) hunt accessible c liff areas from
above, the mountain goat population will decline.
During the past 20 years, hunter success in District 240 averaged 51 percent, or 37 goats killed annually. The population probably declined somewhat. The in a c c e s s ib ility o f many goats to hunters, who are not physically conditioned for a strenuous hunt or have only limited time to hunt, averts 100 percent hunter success.
This, I feel, is a desirable situation, as goat hunting remains a 183
rugged challenge testing the hunter's physical endurance and back country skills. Thirty-seven hunters are rewarded with a trophy animal for their efforts while the remainder receive the chance to bag a goat and can enjoy a tru ly wilderness experience. Building roads adjacent to goat range will not change the behavior of true sportsmen who appreciate the challenge of the hunt; such sportsmen will continue to seek the goat on foot or horseback in the Wilderness Area. But among the ks percent of permit holders who are normally unsuccessful are a few who will take advantage of logging roads via foot, motorcycle, snowmobile, or automobile and "get their goat" the easy way. Hunting success w ill subsequently rise at the expense of the more accessible herds.
The solution is not to drastically reduce permit quotas, allowing fewer sportsmen the opportunity to hunt, but to maintain the challenge of the hunt for as many as possible. Since the political boundaries of the Selway-Bitterroot Wilderness do not coincide with the ecological needs of mountain goats, steps must be taken to protect each herd. My recommendations are th at:
1) proposed timber sales on ridgetops adjacent to goat range be harvested by advanced logging systems (helicopter or baloon) if at all poss ib le ;
2) if conventional systems must be used, a b u ffer zone 0.5 m ile
(0 .8 km) or more in breadth remain unroaded adjacent to goat range and roads constructed beyond that zone be closed and seeded follow ing logging activities. CHAPTER VI
SUMMARY
Ecology of mountain goats in a seven-drainage portion of the
Bitterroot Mountains, Montana, was investigated between January 1973 and June 1975. Six individual goat herds occupied restricted, traditional, winter ranges in each of the drainages from November to mid-June each year. Four miles (6.4 km) of precipitous, cliffy terrain on lower south-facing canyon w alls constituted w in ter h a b ita t. During
June, goats migrated 5 to 10 miles (8 to 16 km) to summer ranges at elevations over 7,000 feet (2,134 m).
Seventy-five percent of the population, estimated at 153 goats in 1975, consisted of animals 2 years of age and older. Productivity declined throughout the study. Kidiadult female ratios of 40:100 in
1 9 7 4 and 42:100 in 1975 followed 2 consecutive severe, prolonged winters. Low natality rates were attributed to in-utero or neonatal losses precipitated by winter stress and delayed spring "green-up".
A 1 8 2 day gestation period followed the 1 December rutting peak. Twice as many goats were counted on ground censuses as aerial surveys.
Intensive study of the Fred Burr herd showed a 25 percent decline in numbers from 1973 to 1975. Natural m o rta lity and hunter harvest both produced significant losses. Natural losses were greatest among kids; hunters killed mostly adults of both sexes.
Three goats were immobilized and marked, two with radio transmitter collars. Other animals, distinguished by horn morphology, also
184 185
provided data on movements, and w in te r range ecology and f i d e l i t y .
Movements on winter ranges were minimal. Adult females occupied
winter-spring home ranges averaging 158 acres (64 ha) in size. Home
ranges o f other age classes were somewhat less. Goats spent the
majority of time in high use areas measuring 17.2 acres (7 ha) or less
in size. Those of socially dominant adult females were situated on
relatively snow-free c liff ledges, while subordinates were on less
optimal h a b ita t. Goats returned each year to th e ir respective herd
winter ranges and possibly to individual high use areas. Snow cover
was an important influence on habitat selection and distribution on
winter ranges. Small, dynamic groups (averaging 1.5 animals) during
winter and spring reduced intraspecific competition and distributed
forage utilization. Thermoregulatory demands and location of lush
forage influenced habitat selection on summer ranges. An adult
female occupied a summer home range 1,456 acres (589 ha) in size.
This reflects the greater mobility of goats and broad distribution
of their biological requirements on summer ranges.
Grasses and sedges comprised the bulk of goat diets during all
seasons and constituted almost 50 percent o f herbaceous forage biomass
on the Fred Burr w in ter range. Shrubs were also important food in winter. Goats spent more time feeding during summer, fa ll, and winter than during spring. Delayed appearance of high quality forage
during spring 1974 and 1975 placed emphasis on energy conservation.
Goats bedded during 54 percent of daylig h t hours in spring and
movements were short until late May. Morning and late afternoon-evening 186 feeding peaks were separated by a midday bedding period throughout the year.
In view of high mortality and low reproductive rates, I recommend a reduction in hunting permits until annual censuses indicate an upward trend in p ro d u c tivity and population numbers. The impacts of increasing recreational use and logging of the Bitterroot Mountains were discussed. I recommended leaving land adjacent to goat winter
ranges roadless to prevent overharvesting accessible herds and to
reduce harassment. REFERENCES CITED
Alden, W. C. 1953- Physiography and glacial geology of western Montana and adjacent areas. U.S. Geol. Survey, Wash., D.C. Prof. Paper 231. 200 pp.
Anderson, N. A. 1940. Mountain goat study. Wa. Dept, of Game, Olympia. Biol. Bull. 2. 21 pp.
Anonymous. 1957. Nutrient requirements of domestic animals: No. V, Nutrient requirements of sheep. Natl. Acad, of Sci., Natl. Res. Council Pub. 504, Wash. D.C. 33 pp.
______. 1 9 5 8 . History of land and water use on irrigated areas. Ravalli County, Montana. Mt. State Engineer, Part 1: State Engineer's Office, Helena, Mt. 8l pp.
. 1 9 6 3 . Big game surveys and investigations - Bitterroot Unit re-check. Job Comp. Rpt., Proj. W- 7 8 -R- 8 , Mt. Fish and Game D ept., Region 2, Missoula. 58 pp.
1 9 6 7 . Big game surveys and investigations - Bitterroot Unit re-check. Job Comp. Rpt., Proj. W-72-R-12, Mt. Fish and Game D ep t., Region 2, Missoula. 48 pp.
1971a. Big game survey and inventory, Bitterroot Unit. Job Prog. Rpt., Proj. W-130-R-2, Mt. Fish and Game Dept., Region 2, Missoula. 68 pp.
1 9 7 1 b. Montana genesis. S teven sville H is to ric a l Society. Mountain Press Publ. Co., Missoula, Mt. 289 pp.
1973a. Big game survey and inventory - Bitterroot Unit. Hob Prog. Rpt., Proj. W-130-R-4, Mt. Fish and Game Dept., Region 2, Missoula. 7 8 pp.
1 9 7 3 b. Bitterroot resource and conservation project. US DA, Soil Cons. S e r v ., Bozeman, Mt. 137 pp.
1973c. 1 9 7 0 Census of population, characteristics of populat ion, Montana. U.S. Dept, of Comm., Bur. of the Census, Wash., D.C. Vol. 1, Chap. A :28-32.
1974a. A plan for Ravalli County - preliminary draft. Rava11i Co. Planning Board, Hamilton, Mt. 170 pp.
1 8 7 1 8 8
1974b. Current population reports, federal - state cooperative program for population estimates. U.S. Dept, of Comm., Bur. of the Census, Wash., D.C. Series P-26(53)*
. 1974c, Environmental statement multiple use plan - Bitterroot North Planning Unit. USES, Region 1, Bitterroot Nat. F o r., S te v e n sv ille Ranger D is t., Mt. 117 pp.
. 1974d. Big game survey and inventory. Job Prog. Rpt., P ro j. W -I3 O-R-5 . Mt. Fish and Game Dept., Region 2, Missoula. 1 2 1 p p .
. 1 9 7 5 . Montana land development, the Montana subdivision inventory project. Environmental Information Center, Helena, Mt. 20 pp.
Arno, S. F. 1970. Ecology of alpine larch (Larix lyal1i Pari.) in the Pacific Northwest. Ph.D. Thesis, Univ. of Mt. , Missoula. 264 pp.
Beaty, C. B. 1962. Asymmetry of stream patterns and topography in the Bitterroot Range, Montana. J. Geol. 70(3):347"354.
Brandborg, S. M. 1955. Life history and management of the mountain goat in Idaho. Id, Dept, of Fish and Game, Boise. Bull. 2. 142 pp.
Casebeer, R. L ., M. J, Rognrud, and S. Brandborg. 1950. The Rocky Mountain goat in Montana. Mt. Fish and Game Comm., Helena. Bui 1. 5 . 1 0 7 pp.
Chadwick, D. H. 1973. Mountain goat ecology - logging relationships in Bunker Creek drainage of western Montana. Job Final Rpt., P ro j. W -I2 0 -R- 3 , 4, Mt. Dept. Fish and Game, Helena. 262 pp.
. 1 9 7 4 . Population characteristics and habitat relation ships of Rocky Mountain goats in Glacier National Park. Ann. R p t., West G la c ie r, Mt. 37 PP.
Cheatum, E. L., and C. W. Servinghaus. 1950. Variations in fertility of white-tailed deer related to range conditions. Trans. N. Am. Wildl. Conf., Wash., D.C. 15:170-190.
Clark, G. M., C. M. Clifford, L. V. Fadness, and E. K. Jones. 1970. Contributions to the ecology of Colorado Tick Fever virus, J. Med. Ent. 7(2): 18 9 -197.
Cole, G. F. 1 9 5 8 . Range survey guide. Mt. Dept. Fish and Game, Helena. Fed. Aid P ro j. W-37~R. 21 pp. 189
Cowan, 1. McT. 1944. Report of wildlife studies in Jasper, Banff, and Yoho National Parks in 1944 and parasites, diseases, and injuries of game animals in the Rocky Mountain National Parks, 1 9 4 2 - 1 9 4 4 . Wildl. Serv., Dept, of Mines and Res., Ottawa, Can. 8 3 pp.
______. 1 9 5 0 . Some vital statistics of big game on overstocked mountain range. Trans. N. Am. Wildl. Conf., Wash., D.C. 15: 5 8 1 - 5 8 8 .
Cowan, R. L., J. S. Jordan, J. L. Grimes, and J. D. Gill. 1970. Comparative nutritive values of forage species. Pages 48-56 Range and w ildlife habitat evaluation - a research symposium. USDA Misc. Pub. 1147- 220 pp.
Craighead, J. J., F. C. Craighead, Jr., R. L. Ruff, and B. W. O'Gara. 1973. Home ranges and activity patterns of nonmigratory elk of the Madison drainage as determined by biotelemetry. Wildl. Mono. No. 3 3 . 5 0 pp.
, M. G. Hornocker, M. W. Shoesmith, and R. I. Ellis. 1969- A marking technique for elk. J. Wildl. Mgt. 33(4):906-909-
Daubenmire, R. and J. Daubenmire. I 9 6 8 . Forest vegetation of eastern Washington and northern Idaho. Wash. Agri. Exp. Stn., Pullman. Tech. Bull. 6 0 . 104 pp.
DeBock, E. A. 1970. On the behavior o f the mountain goat (Oreamnos americanus) in Kootenay National Park. M.S. Thesis, Univ. of A lb e rta , Edmonton. 173 pp.
D ie tz , D. R. 1965- Deer n u tr itio n and research in range management. Trans. N. Am. Wildl, Conf., Wash., D.C. 30:274-285.
Edwards, R. Y. 1956. Snow depths and ungulate abundance in the mountains o f western Canada. J. W ild l. Mgt. 2 0 (2 ): 159"168.
Foss, A. J. 1 9 6 2 . A study of the Rocky Mountain goat in Montana. M.S. Thesis, Mt. State Univ., Bozeman. 26 pp.
G e is t, V. 1 9 6 4 . On the rutting behavior of the mountain goat. J. Mamm. 45(4):551"568.
. 1 9 7 1 . Mountain sheep - a study in behavior and evolution. Univ. Chicago Press, Chicago. 3 8 3 pp.
Gregson, J. D. 1956. The Ixodoidea of Canada. Can. Dept. A gri. Sci. Serv., Ent. Div,, Ottawa, Can. Pub. No. 930. 92 pp. 190
Guiguet, C. 1951. An account of wolverine attacking mountain goat. Can. Field Nat. 65:187.
Halls, L. K. and T. R. Dell. 1966. Trial of ranked-set sampling for forage yields. For. Sci. 12(l):22-26.
Hanson, W. 0. 1950. The mountain goat in South Dakota. Ph.D. Thesis, Univ. of Mi., Ann Arbor. 92 pp.
Hebert, D. M, 1973. Altitudinal migration as a factor in the nutrition of bighorn sheep. Ph.D. Thesis, Univ. of B.C., Vancouver. 356 pp.
Hibbs, L. D., F, A. Glover, and D. L. Gilbert. 1969. The mountain goat in Colorado. Trans. N. Am. Wildl. Conf., Wash., D.C. 34: 409-418.
Hitchcock, C. L. and A. Cronquist. 1973. Flora of the Pacific Northwest. Univ. of Wa. Press, Seattle. 730 pp.
Hjeljord, 0. G. 1971. Feeding ecology and habitat preference of the mountain goat in Alaska. M.S. Thesis, Univ. of Ak., Fairbanks. 126 pp.
Holroyd, J. C. 1967. Observations of Rocky Mountain goats on Mount Wardle, Kootenay National Park, British Columbia. Can. Field Nat. 81(1):1-22.
Hornocker, M, 1970. An analysis of mountain lion predation upon mule deer and elk in the Idaho Primitive Area. Wildl. Mono. No. 21. 57 pp.
Isdahl, C. J. 1 9 7 6 . Crude protein analysis of nineteen plants used by Rocky Mountain goats in winter. Sr. Thesis, Univ. of M t., Missoula. 19 pp.
Jellison, W. L. and G. M. Kohls. 1938. Tick-host anemia: a secondary anemia induced by Dermacentor andersoni Stiles. J. Paras it. 2 4 (2 ): 1 4 3 - 1 5 4 .
Johnson, M. C. 1972. Wood products in Montana. Mt. Bus. Qtrly., Missoula. 10(2):30.
Johnston, A,, L. M. Bezeau, and S. Smoliak. I 9 6 8 . Chemical composition and in vitro digestibility of alpine tundra plants. J. Wildl. Mgt. 32(4):773-777.
Julander, 0., W. L. Robinette, and D. A. Jones. I 9 6 I. Relation of summer range condition to mule deer herd productivity. J. Wildl. Mgt. 2 5 ( 1 ): 5 4 - 6 0 . 191
Kerr, G. R. and J. C. Holmes. 19^6. Parasites of mountain goats in West Central A lberta. J. W ild l. Mgt. 30 ( ^ ) : 786-790.
Klein, D. R. 1953. A reconnaissance study of the mountain goat in Alaska. M.S. Thesis, Univ. of Ak., Fairbanks. 121 pp.
Koch, E. 1941. Big game in Montana from early h is to ric a l records. J. Wildl. Mgt. 5(4): 357-370.
Knoche, K. G. 1968. The ecology of the Rattlesnake, Montana mule deer range. M.S. Thesis, Univ. of Mt., Missoula. 152 pp.
Kuck, L. 1973a. Rocky Mountain goat ecology. Prog. Rpt., P-R Proj. W-144-R-3. Id. Fish and Game Dept., Boise. 72 pp.
______. 1 9 7 3 b. Rocky Mountain goat ecology. Prog. Rpt., P-R Proj. W-144-R-4. Id. Fish and Game Dept., Boise. 6 3 pp.
Lackschewitz, K. H. 1970. Alpine and timberline flora in the B itte rro o t Mountains, Montana. Proc. Mt. Acad. S c i., Missoula. 30:1-30.
Langton, C. M. 1935. Geology of the northeastern part of the Idaho batholith and adjacent region in Montana. J. Geol. 43(l):27“60.
Lentfer, J. W. 1955. A two-year study of the Rocky Mountain goat in the Crazy Mountains, Montana. J. Wildl, Mgt. 19(4):4l7-429-
Lindgren, W. 1904. A geological reconnaissance across the Bitterroot Range and Clearwater Mountains in Montana and Idaho. U.S. Geol. Survey, Wash., D.C. Prof. Paper 27- 22 pp.
McMurtrey, R. G., R. L. Konîzeski, F. S term itz, and H. A. Swenson. 1 9 5 9 . Preliminary report on the geology and water resources of the Bitterroot Valley, Montana. Mt. Bur. Mines and Geol., Butte. B u ll. 9 . 4 7 pp.
, ______, M. V. Johnson, J. H. Bartel Is , and H. A. Swenson. 1 9 7 2 . Geology and water resources of the Bitterroot Valley, southwestern Montana. Geol. Survey, Wash., D.C. Water-Supply Paper I 8 8 9 . 8 0 pp. -
Miller, R. F., G. H. Hart, and H. H. Cole. 1942. Fertility in sheep as affected by nutrition during the breeding season and pregnancy Ca. Agr. Exp. S tn ., Berkeley. B u ll. 6 7 2 . pp. 3-31.
Moustgaard, J. 1959. Nutrition and reproduction in domestic animals. Chapter i n H. H. Cole and P. T. Cupps, eds., Reproduction in domestic animals. Academic Press, New York. 451 pp. 192
Murphy, D. A. and J. A. Coates. 1966. Effects of dietary protein on deer. Trans. N. Am. Wildl. Conf., Wash. D.C. 31:129-139"
Peck, S. V. 1 9 7 2 . The ecology of the Rocky Mountain goat in the Spanish Peaks area of southwestern Montana. M.S. Thesis, Mt. State U n iv ., Bozeman. 54 pp.
Petocz, R. G. 1 9 7 3 . The effect of snow cover on the social behavior of bighorn rams and mountain goats. Can. J. Zool. 51 (9 ):987-993"
Pfister, R., S. Arno, R. Presby, and B. Koval chick. 1972. Preliminary forest habitat types of western Montana. USDA For. Serv., Interm tn. For. and Range Exp. S tn ., and Region 1, Missoula, Mt. 75 pp.
Ransom, A. B. 1967. Reproductive biology of white-tailed deer in Manitoba. J. Wildl. Mgt. 31 ( 1): 114-123.
Ream, R ., B. B e a ll, and L. Marcum. 1971. Sapphire Range e lk ecology study - elk, logging and people. 1st Ann. Rpt. School of For. Univ. o f M t., Missoula. 28 pp.
Rideout, C. B. 1974. A radio telemetry study of the ecology and behavior of the Rocky Mountain goat in western Montana. Ph.D. Thesis, Univ. of Ks., Lawrence. 146 pp.
Ritzman, E. G ., and F. G. Benedict. 1931. The heat production of sheep under varying conditions. N.H. Agri. Exp. Stn.,Durham. Tech. Bull. 3 4 . 3 2 pp.
Ross, C. P. 1 9 5 0 . The eastern fro n t o f the B itte rro o t Range, Montana. U.S. Geol. Survey, Wash., D.C. Bull. 974-E: 135~174.
Saunders, J. K., Jr. 1955. Food habits and range use of the Rocky Mountain goat in the Crazy Mountains, Montana. J. Wildl. Mgt. 19(4):429-437.
Seton, E. T. 1953. Lives of game animals. Vol. 3, Part 2. Charles T. Brandford Co., Boston. pp. 469-515.
Shahinen, U. M. 1957. Mines and mineral deposits Missoula and Ravalli counties, Montana. Mt. Bur. Mines and Geol., Butte. B u ll. 8. 6 3 pp.
Stelfox, J. G. 1 9 7 5 . Range ecology of Rocky Mountain bighorn sheep in Canadian national parks. Ph.D. Thesis, Univ. of M t., Missoula. 202 pp. 193
Sullivan, J. T. 1962. Evaluation of forage crops by chemical analysis a critique. Agron. J. 54(6):511-515.
Swenson, L. K. 1973. A lite r a tu r e review on the n a ta lity concept in wild North American ruminant populations. Co. Game, Fish and Parks D ept., Div. o f W ild l., Denver. Spec. Rpt. 30* 10 pp.
Thompson, A. M ., and W. Thompson. 1948. Lambing in re la tio n to the diet of the pregnant ewe. Brit. J. Nutrition 2(4):290-305.
Thorne, T. 1971. Nutritional requirements of elk for reproduction. Proc. Western Assoc. State Game and Fish Commissioners, Snowmass- at-Aspen, Co. 51:403-414.
Vaughan, M. R. 1975. Aspects of mountain goat ecology, Wallowa, Oregon. M.S. Thesis, Or. State Univ., Corvallis. 113 pp.
Verme, L. J. 1962. Mortality of white-tailed deer fawns in relation to nutrition. Proc. First Natl. White-Tailed Deer Sym., Athens, Ga. pp. 1 5 - 2 8 .
1 9 6 3 . Effect of nutrition on growth of white-tailed deer fawns. Proc. N. Am. WÎ1d1. Conf., Wash., D.C. 28:431-443* APPENDIX A
HAB1 TAT TYPES
Key to Overstory Types
Abb re v î at î on Spec i es
01 - None No overstory
02 - PP P Î nus ponderosa
03 - OF Pseudotsuga menziesii
04 - PP/DF P i nus ponderosa/Pseudotsuga menzieii
05 - AF/AL Ab Î es 1 asiocarpa/Larix l y a l l i î
06 — LP P i nus contorta
07 - AF Ab Î es 1 as i ocarpa
08 - AL Lar i X l y a l 1i i
09 - WBP P i nus albicauli s
10 - Krumholtz Ab i es 1 as iocarpa
P i cea engelmann i i
P 1 nus a lb i cauli s
Habitat Combinations
Understory Type Associated Overstory Types
01 - Water 01®
02 - Bare rock A11 types may occur
03 - Snow field A11 types may occur
04 - T undra 10
194 1 95
Understory Type Associated Overstory Types
05 - Bunchgrass 02-04, 07
06 - Grouse whortleberry-woodbrush 05» 07-09
07 - Beargrass-herb 03, 05, 07-09
08 - Deciduous shrub 02-04, 06
09 - Erlcaceous shrub 03, 06, 07
10^ - Scattered herb 02-04
10^ - Scattered herb 05, 07-09
11 - Heath-herb mat 05, 07-09
12 - Senecio-sedge 03, 05, 07-09
13 “ Moist herbaceous mat 05, 07, 08
14 - Creek bottom 03, 06, 07
^Any of the 14 understory types may lack overstory.
^Winter range.
^Summer range. APPENDIX B
LIST OF UNDERSTORY PLANT SPECIES
Occurrence in Species Understory Types
Selag i n e l1aceae Se Iag Î n e lla densa AH wa11 ace : 05, 08, 09, 10 , 14
Poly pod i aceae Asp Î d o tÎ s densa 05, 08, 09, icf, 12 Athyriurn f i 1ix-femina 14 Chei1anthes graci11ima 05, 10®, 12 Cryptogramma crispa 04-08, 10-12 Polyst i chum 1onch i t is 05, 09, 11-14 Woods ia scopu1i na 05, 0 8 , 10®
Cupressaceae Juniperus communis 04-08, 10, 11 scopulorum 05, 0 8
Taxaceae Taxus b r e v ifo lia 14
Gram i neae Agropyron spicatum 05 07, 0 8 , lo f, 12, 14 Agros t i s scabra 05 07, 0 8 , 10-12, 14 A. variabilis 04 0 6 , lOb, 11-13 Bromus marg i natus 05 0 8 , los, 1 2 , 14 2' tectorum 05 0 8 , 103. 14 Ca1amag ros t i s canadens i s 05 10, 14 C^. purpurascens 04 0 6 , lOb 11 C_. rubescens 05 14 Danthoni a i ntermed ia 07 10' , 1 1 Deschamps i a atropurpu rea 04 07, lob-13 2" caesp i tosa 05 0 6 -08, 10-13 2* danthanoi des 05 0 8 Elymus g 1aucus 05 12-14 Festuca Idahoens is 05 0 8 , 10^ 2* ovi na var. brevi folia 04 06, lob, 11 Koeleria cristata 05 07, 0 8 , 10^ 0ryzopsis exÎgua 05 0 6 , 10, 11 Ph1eum pratense 14 Poa bulbosa 05
196 197
Occurrence în Spec î es Understory Types
P canby î 05, 08, 10^ P gracil lima 04, 05-08, 10, 11 P ï nter îor 04, 07, 11-13 2 ______nevadens î s 05, 08 £.* sandberg î i 05-08, 10, 11
Cyperaceae Carex geyerî 05 08-10^, 12, 14 C, 1 as îocarpa 05 10*, 12 C. mertens i î 07 10^-13 £• n i g r i cans 04 06, 07, 0 9 - 1 3 C. payson i s 12 13 C. phaeocepha1 a 04 06, 07, 11 C. sci rpQîdea var. stenoc 1 aena 07 09, 10^ 1 1 LuzuT a g 1abrata 06 10&, 11 13 parrî flora 06 07, 10^ 11 spîcata 04 06, 11
Juncaceae Juneus drummondi i 04, 06, 07, 1 0 » - 1 2 J . me rtens î anus 07, 10-13 J. p a rry i 04, 06, 11 J. regai 1î î 12, 14
L i 1î aceae A llium cernuum 0 5 , 0 8 , îo r. 14 Brodiaea douglasîi 0 5 , 0 8 , 1 0 ^ Calochortus elegans n , 13 Clintonia unifiera 09, 14 Dîsporum hookeri 14 Erythronium grandîflorum 05, 07, 09-14 Frîtillaria pudîca 0 5 , 08, 1 0 ““ Sm ilacina racemosa 09, 14 S. s te l 1 ata 05, 14 Streptopus amplexifolîus 09, 14 T ri 1î um ovatum 07, 09, 14 Veratrum vîride 07, 09, 1 0 », 12-14 Xerophyllum tenax 05-07, 09-14 Zigadenus venenosus 0 5 , 0 8 , loa. 14 Z. elegans 1 1 , 1 2
Orchîdaceae Calypso bulbosa 09, 14 Goodyera obi o n g îfo lia 05, 09, ICf, 1 2 , 14 Habenarîa dilatata 05,' 09, 14 1 9 8
Occurrence în Spec î es
Sa 1î caceae Sa1îX sp. 04- 06, 08-12, 1
Betu1aceae Al nus s i nuata 05, 07- 10^, 12,
Polygonaceae Erîogonum flavum 07, 09, 1 1 pyroiaefolî um 04, 06 umbel 1atum 05, 08, 10^ Oxyria d î gyna 07, 11, 13 Polygonum b i s to rto i des 12, 13 P^. doug 1 as î î 05, 08, 10^ £.* phytolaccaefol î um 05, 07, 09-13
Portulacaceae C1ayton i a lanceolata 05, 07, 09-13 Lewî s î a red i vi va 05, 10^ Mont i a cord î f o lî a 12, 13
Caryophyl1aceae Arenr î a cap î 1la r î s 04, 07 A* congesta 05, 07, 08, 10, obtus i 1oba 04, 06 Cerast i um a rvense 05, 08, 103, 12 S î 1ene doug1 as i î 05, 0 8
Ranuncülaceae Actaea rubra 09, 14 Aquilegia f 1avescens 09, 12 C1ema t î s columbi ana 14 Delphinium n u ttal1i anum 05, 08, lO f, 11 Ranunculus escholtz î î 07, 09, 11-13 A* g 1aberrîmus 05, 08, 103, 14 Tha1î et rum occ îd en ta1e 07, 09, 14
Berber î daceae B erberî s repens 05, 0 8 , 10^, 14
Crue î ferae Arabîs hoboel1iî v a r . col 1t ns î î 05, 08, 10^ A. l y a l 1î i 04, 06, 07 A. m i crophy11 a 05, 07 A. n u tta 11Iî 07,, 11 , 13 Draba apï eu 1 ata var. davîesîae 04, 11 2- payson i î v a r . trele as i i 04 Smelowskia ca1cyna 04, 10^ , 11 199
Occurrence în Spec î es Understory Types
Crassu1aceae Sedum 1anceolatum 04, 0 6 , lob , 11 2" stenopetalum 05. 0 8 . 103
Saxi fragaceae Heuchera cy1î nd rî ca 05. 07, 1 03 , 1 2 , 14 H. g rossulari i foli a 09, 10&, 1 1 , 13 Saxifraga arguta 07, 09, 13 occ î denta1ï s 07. 09, lob , 11 2" rhomboi dea 05, 103, 12 toim i e i 04, lOb Suksdorf i a ranuncu1î fo lî a 05. 10
Grossularîaceae R î bes cereum 05, 07-103, 14 1acustre 09, 1 2 , 14 i * V iscos i ssImum 05, 0 8 , 103
Hydrangeaceae Phi 1adelphus 1ewî s t î 05, 0 8 , 103 , 12
Rosaceae Amelanchîer alnîfolîa 05, 07-103, 1 2 , 14 Fragarîa vesca 05, 08-1Q3 Z." vî rgînîana 05, 1 2 , 14 Geum ross i l var. turbî natum 04, 07, 0 8 , 103 Holodîscus discolor 05, 07, 08. 1 0 ^ Ives i a go rdon i î 04, 07, 10° Luetkea pect i nata 07, 1 2 , 13 Petrophyturn caespi tosum 05, 1 0 , 11 Physocarpus malvaceus 0 8 , 14 Potent ilia d i vers i fo li a 04, lob- 13 P^. gl andulosa 05, 0 8 . 10- 12 Prunus emarg i nata 0 8 , 14 Z-* virgîniana 05. 0 8 , 103 , 12 Rosa gymnocarpa 07, 09, 14 nutkana 07, 09 woods i i 05. 0 8 , 14 Rubus îdaeus 05, 0 6 - 1 0 , 14 R^. parri f lorus 05, 07, 09, 1 2 , 14 Sîbbaldia procumbens 04, 07, lob Sorbus scopuli na 0 8 , 09, 14 Sp i rea betuli fo li a 05, 0 8 , 09, 14 S. d e n s iflo ra 07, ,09, 12
Leguminosae As t ragalus sp. 05 Lup i nus polyphy11 us 05, 0 8 , 09, 14 200
Occurrence în Spec? es Understory Types
Geran îaceae E rod Ium c î rcu tar î um 05, 10^
Cel ast raceae Pachîstîma myrs intes 07, 09, 14
Aceraceae Acer g 1abrum 05, 07-103, 12, 14
Rhamnaceae Ceanothus velutînus 05, 07, 08, 14
Hyperîcaceae HyperÎ cum formosum 07, 09, 10^-13
Violaceae V io la adunca 0 9, 10°-13 o rb ic u la ta 05, 103, 12, 14
Elaegnaceae Shepherd i a canadens î s 09, 14
Onag raceae EpolobIum a1p îuum 04, 06, 10^, 11 angust i f o iÎ um 05, 08 mlnutum 0 5 , 0 8 , 103 —• pan!culatum 0 5 , 08 Gayophyturn hum!1e 05
Umbel 1i ferae Heracieum 1anatum 14 LÎ gust ÎCÎ um canby i 12, 13 Lomet Î um d issectum v a r. mult Î f i dum 05, 08 L. triternatum 11
Cornaceae Cornus canadensis 09, 14 stolon Î fera 05, 08, 14
Ericaceae Arctostaphy1 os uva-urs i 05, 07-09, 14 Cass iope mertens i ana 07, 11 C^. tetragona 04 Chîmaphî1 a umbel la ta 09,. 14 Ka1m i a poll f o lia 13 Ledum g 1andulosum 07, 09, 13 Menziesia ferrug inea 07, 09, 12-14 201
Occurrence în Spec i es Understory Types
Phy1lodoce empetrî formi s 06, 07, 10^-13 P_. glandul î flo ra 04, 06, 07, 11 Pyroi a secunda 09, 14 Rhododend ron a 1b î f 1orum 07, 09 Vacc î n î um membranaceum 06, 07, 09, 11 m y rtîllu s 07, 11 jy. scopar i um 05, 07, 09, 12-14
Primulaceae Dodecatheon jeffrey i 09, 12-14 D. pauciflorum 05, 07, 09-14
Gent î anaceae Gent i an calycosa 10' 12, 13
Apocynaceae Apocynum androsaemî fo lî um 07
Polemonî aceae L i nanthus septentrionalîs 05, 08 Phlox d i ffusa 10&, 11 P^. pul y i nata 04. lob 11 Polemon î um pulcherr î um lOD-13 P. vîscosum 04, lOb
Hydrophy11aceae Phacelîa hastata 05, 11 P. l y a l l i î 04, 07, lob
Borag î naceae Eritrichîum nanum var. elongatum 04 Hackelîa c^nerea 05, 08, 103 Mertensîa ciliata 09, 12
Scrophular î aceae Castîlleja mînîata 05. 08” 10, 14 C. rhexîfolia 0 6 , 11 Chtonophîla tweedy! 04, lob Mimu 1 us 1ewis ï i 11- 13 Pedicularis bracteosa 07, 13 P. contorta 04, 07, lOb, 11 P. groenlandica 12, 13 Penstemon alb ertin u s 05, 07, 11 P. d î phy11 us 05, 1 0^ P, ellîptieus 0 6 , 07, lob, 11 202
Occurrence în Spec i es Understory Types
£.* f 1 avescens 07, lob, 11 P^. procerus 05, 12 Synth r i s p î nnat i f î da 04 Veron i ca eusî cki î 13
Rub î aceae Gaii um trî florum 09, 14
Capr î fo li aceae L î nnaea borea1i s 14 Lonicera utahensîs 09, 14 Sambucus 05, 14 Symphorîcarpos a 1 bus 0 8 , 14
Valerî anaceae Valeriana sîtchensîs 07, 12
Campanulaceae Campanula p a rry î var. îdahoensîs 07, lob , 11, 13 C. rotund î fol i a 05
Compos î tae Ach ille a mi 1lefolîum 05, 07, 0 8 , 10, 11 Anapha1î s margar î taceae 05, 07, 08, 12, 14 Antenna rla alpîna 04, 06, 1 ob 1anata 04, 06, 07, lob. 11 _A. mIcrophy 1 1 a 05, 08 —• TQsea 05, 10, 11 _A. umbri nel 1 a 05, 1 0^ Arn i ca cord î f o li a va r . cord i fo 11 a 09, 14 _A. la tî f o lia va r . g rac il is 04, 07, 11 A* J_* v a r . 1 at î fol î a 05, 07, 09, 14 Artemes î a 1udovi ci ana 05, 0 8 , 103 As ter conspicuous 05, 08, loa A* ^olîaceus 06, 07. lob. 1 1 A. occ i de n ta lî s 11 , 13 Balsamorh i za sag i tta ta 05, 08 Centaurea maculosa 14 Crep i s at rabarba 05, 08 Er i ge ron acris 11 , 12 caesp î tosus 05, 0 8 , 10^ compos i tus 04, 06, lob El' Pereg r i nus 07, 11- 13 s implex 04,, lOb . 11 Gnapha1i um pa1ustre 05 Hierac îum a lb i f 1orum 07, 09, 10, 12 ü* cynoglossoides 05, 08. loa 203
Occurrence în Spec î es Understory Types
j4. g raci \ e 04, 07, lob, n Senecio canus 05 —• i ntegerrïmus 05, 07 2' triangularîs 07. 09, ICr-14 Solî dago missourîensîs 05, 08 S. multïvad i ata 1 ot>, n , 13
^Winter range.
^Summer range.
Scientific names after Hitchcock and Cronquist 1973.