The Bison of Yellowstone National Park

BISON OF YELLOWSTONE NATIONAL PARK QL 737 .U53 M4 1973

BRIGHAM YOUNG UNIVERSITY

3 1197 22177 9835 THE BISON OF YELLOWSTONE NATIONAL FARK

Margaret Mary Meagher Research Biologist National Park Service

National Park Service Scientific Monograph Series Number One 1973 Richard Nixon President of the United States

Rogers C. B. Morton, Secretary U.S. Department of the Interior

Ronald H. Walker, Director National Park Service

As the Nation's principal conservation agency, the Department of the Interior has basic responsibilities for water, fish, wildlife, mineral, land, park, and recreational resources. Indian and Territorial affairs are other major concerns of America's "Depart- ment of Natural Resources." The Department works to assure the wisest choice in managing all our resources so each will make its full contribution to a better United States-now and in the future.

This publication is one in, a series of research studies devoted to special topics which have been explored in connection with the various areas in the National Park System. It is printed at the Government Printing Office and may be purchased from the Superintendent of Documents, Government Printing Office, Washington, D.C. 20402. Price $2.25. Stock No. 2405-00524

Library of Congress Catalog Card Number: 73-600221 Acknowledgmen ts

THIS RESEARCH WAS UNDERTAKEN with the Sponsorship of the National Park Service and the Museum of Verte- brate Zoology, University of California, Berkeley. The research report, accepted as a doctoral dissertation in 1970 by the University of California, is presented here with minor modifications.

The project, conducted over a span of 7 years while I was employed as a Park Naturalist by the National Park Service at Yellowstone National Park, would not have been possible without the assistance of many people. Among the National Park Service personnel who contributed, particular appre- ciation is due John Good, former Chief Park Naturalist, for encouragement and assistance in arranging work requirements to allow time for the study. Park Rangers Peter Thompson, Dale Nuss, and Gordon Boyd assisted with some of the field work. Biologist Glen Cole contributed ideas and suggestions. Aubrey Haines provided information on historical sources. Dave Stradley, Gallatin Flying Service, made possible the quality of the aerial observation work. Kenneth Greer, Su- pervisor of the Montana State Fish and Game Department Laboratory, provided food habits analysis assistance. W. E. Booth, Montana State University, verified plant identifica- tions. John Ricks, Livingston, Montana, facilitated autopsy work. Keith Hoofnagle did the maps and graphs. Financial support was provided by the National Park Service and the Union Foundation Wildlife Fund, administered by the University of California. The Yellowstone Li- brary and Museum Association contributed to the reproduction of dissertation copies. To these people and organizations, and the many other individuals who provided information, encouragement, and assistance—my thanks. juiy 1972 Margaret Mary Meagher [Digitized by the Internet Archive

in 2014

https://archive.org/details/bisonofyellowstoOOmeag Summary

Objectives OF this study were to provide basic data on the life history, habits, and ecology of bison in Yellow- stone National Park. The original population of bison in historic times consisted of mountain bison, Bison bison athabascae. In spite of poaching to near-extermination by about 1901, a remnant of the subspecies survived and increased. Interbreeding with a population of plains bison, B. b. bison, introduced in 1902, began by the 1920s. The present bison population consists of hybrid descendants of the two subspecies. The present wintering distribution within the park approximates that of the historic population, occurring in the three subunits of Lamar, Pelican, and Mary Mountain, none of which are geographically isolated from the others. The present summering population approximates the historic distribution only in the Upper Lamar-Mirror Plateau and Hayden Valley areas. A large west-side and a large northern summering population are lacking. Present (1968) numbers are half or less than those of probable historic numbers. Examination of 71 females killed for population reduction purposes indicated that sexual maturity was not reached by most until 4 years of age, later than recorded some years ago. The observed pregnancy rate of 52% for females 2.5 years and older was also less than formerly recorded in Yellowstone. Brucellosis was not a factor which affected reproduction. Records and observations suggested that both calving season (in May on the winter ranges) and the breeding season (in late July to early August on the summer ranges) were shorter than formerly. The observed changes may reflect the shift from a semiranched population to a wild one. Records from live-trapping operations in 1964-66 provided sex and age structure information. The records suggested that female survival was favored during the calf year, but that male survival was favored the next 3 years of life, after which differential survival could not be distinguished from the records. Adult bulls outnumbered adult cows, but this could be attributed to earlier reductions. Age classes of the wintering population in the Mary Mountain area in 1964-65 were: calves, 16%; yearlings, 11%; 2.5-year-olds, 6%; 3.5-year-olds, 5%; and adults, 62%. These may change somewhat after a period with no reductions. Observed spring calf percentages of mixed herd numbers for 3 of 5 years were 19-20%. Percentages of total population were approximately 11%. These percentages may also change if reductions are not made. Significant mortality of calves at birth or just before or after was suggested by limited data. Thereafter, little mortality occurred during the first year. Nearly half the calves which survived into their first winter died before 2.5 years of age. Recruitment into the population occurred with survival to 3 years of age. Population trends suggested that increases in the population were often very slow. Reductions by man apparently were not the sole factor which caused population decreases nor retarded increases. Parasites, diseases, predation, and emigration were not important. Environmental factors culminating in usual and more-than-usual winter mortality appeared important. Herd groups followed definite patterns of seasonal movement. Spring migrations to summer ranges, occurring by the second week of June, appeared to be influenced by weather patterns and temperatures rather than snow melt or vegetation changes. Temporary fall movements occurred in conjunction with fall storms at higher elevations; final movements to winter ranges occurred by mid- November. Bull movements were somewhat more irregular. Movements and distribution on summer range areas appeared more influenced by the presence of biting flies than by possible factors of breeding activity and vegetation changes. A species of Symphoromyia of the Rhagionidae was implicated. Mixing and interchange between population subunits resulted in designation of three herds according to their use of winter range areas. These three subunits formed two breeding populations in summer. Little contact occurred between members of these two populations at any time. The limited neckband information on marked adult cows suggested that they have an affinity for a given winter range regardless of summer movements. Temporary shifts of population segments from one winter range to another

have occurred. Thus, although no population segment is isolated from another, the three exist as fairly separate en- tities in terms of winter range. This may explain the lack of population emigration to and reestablishment on unoccu- pied ranges either within or outside the park since historic times. Analysis of 22 rumen samples showed that sedge was the most important forage item. Sedge, rush, and grasses provided 96% of the diet volume throughout the year. Forage availability did not appear to be a population-limiting factor under most conditions. Population numbers in Pelican over a span of many years suggested that the levels were regulated by environmental influences which resulted in low reproduction and low increment rates. Larger increases in numbers during favorable periods have been offset periodically by heavy mortality during more severe winters. The minimum population level in this area may be governed by the presence of scattered thermal areas used in winter stress periods. A combination of factors such as extensive sedge bottoms together with some sagebrush-grassland uplands, open streams, and thermal areas may allow habitation over time by mixed herd groups of bison in this wintering valley.

Contents

ACKNOWLEDGMENTS SUMMARY

Chapter 1 INTRODUCTION

Methods 1

Chapter 2 THE STUDY AREA Physiography 3 Climate 8 Vegetation 9 History 10

Chapter 3 THE BISON POPULATION The historic population 13 Mountain bison 14 Numbers and distribution through 1902 17 The present population 26 Origins 26 Present composition 27 Numbers and distribution 29

Chapter 4 GENERAL CHARACTERISTICS Physical characteristics 38 Appearance 38 Weight 38 Life Span 46 Behavioral characteristics 46

Grouping characteristics 46 Behavior and specific circumstances 47 Senses and disposition 47 Visitor opportunities to see bison 49 1 1

Chapter 5 POPULATION CHARACTERISTICS Sexual maturity 50 Reproduction rate 5 Fetal sex ratio 56 Number of young at birth 58 Population structure 58 Calf percentages 60 Mortality 62 Calf Mortality 62 Subadult mortality 64 Other mortality 65 Population trends 65

Chapter 6 MORTALITY FACTORS Parasites 69

Internal parasites 69 External parasites 69 Diseases 70 Predation 72 Other causes 73

Chapter 7 HABITS Calving 75 Rut 76 Movements 77 Migratory movements 77 Summer range movements 8 Winter range movements 84 Movements beyond park boundaries 85 Mixing of population segments 85 Food habits 90

Chapter 8 HABITAT RELATIONSHIPS Use of forage areas 96 Use of thermal areas 98 Effects on habitat 103 1

Page

Chapter 9 SUGGESTED MECHANISMS OF POPULATION REGULATION 110 APPENDICES

I Common and scientific names of plants 114 II Summary of bison reports prior to 1903, 116 Yellowstone National Park and vicinity III Reports of wild bison, 1903-19, Yellowstone National Park 136 IV Bison population, 1902-68 144 V Data on fetal sizes compiled from

tabulation of late January 1 94 (Skinner 1941) 148 VI Known bison movements to and beyond Yellowstone National Park boundaries, 1942-67 149 VII Occurrence of grasses and grasslike plants in bison use areas 150

xi Figures

1 Map of Yellowstone National Park showing study area 4

2 Aerial view of a part of the forested plateau 5

3 Springtime view west across lower Lamar Valley 6

4 Upper Lamar drainage, Absaroka Mountains in background 6

5 Bison on the Pelican Valley winter range 7

6 A part of the Hayden Valley winter range 7

7 Lower Geyser Basin, Firehole winter range, early spring 8

8 Summer range on the western part of the Pitchstone Plateau 9

9 Cows and calves, Hayden Valley, sometime before 1894. 15

10 Skulls of Bison bison athabascae and B. b. bison 16

11 Map of bison distribution and movements in historic times 24

12 Bison wintering in Hayden Valley prior to 1894. 25

13 Buffalo Jones and Army Scout Holt with captured bison calf 27

14 Clipped appearance of a mature bull. 39

15 Bison shedding old hair, mid-summer 40

16 Wisps of shed bison hair on a branch of a lodgepole pine 41

17 Newly-born calves in a mixed herd group. 41

18 Calf that has lost its first red-brown pelage. 42

19 Head shape and size of cow compared with bull 42 xii Page

20 Spike-horn bull, approximately 2.5 years old. 43

21 Spike-horn bull, yearling female, cows, and bull. 44

22 Horns of adult cow and spike-horn bull compared 44

23 Old Tex, a record Yellowstone bull 45

24 Bison population trends from population counts, 1936-68 66

25 Trench left in soft snow by traveling bison 73

26 Bull bison foraging in snow approximately 2.5 feet deep 74

27 Feeding site in snow approximately 2 feet deep 74

28 Calves a few days old 76

29 Grassy spot uprooted by bison horning during the rut 77

30 Map of the Lamar-Pelican area 79

31 Map of Hayden Valley-Firehole-Madison Plateau area 80

32 Bison herd groups on Alum Creek, Hayden Valley 81

33 Bison on the strip of sedge meadows along upper Alum Creek 82

34 A herd group on the east boundary near Canoe Lake 83

35 Map showing bison movements across park boundaries 86 36 Neckbanded bison in a group at Pocket Basin on the Firehole. 87

37 Population fluctuations in wintering areas caused by shifts 87

38 Snow-free bison feeding site on warm ground in Firehole 98

xiii 1

Page

39 The same site shown in Figure 38, in early summer 99

40 Warm site along Alum Creek in Hayden Valley 99

41 The same site shown in Figure 40, in summer 100

42 Bison bull wintering among active geysers and hot springs 100

43 Aerial view of the Alum Creek winter feeding area. 101

44 Hot water keeps Firehole River open all winter 101

45 Sedge growth along Firehole River provides winter forage 102

46 Bison in small thermal area west of Astringent Creek 103

47 Trees debarked by rubbing bison, Hayden Valley 104

48 Bison horning effects on a lodgepole pine 105

49 Bull bison at a wallow which is used year after year 106

50 A bison trail, Hayden Valley area 107

51 Pelican Valley population numbers, 1902-68 1 1

xiv Tables

1 Vegetation of the study area

2 Summary, native bison information 1860-1915

3 Composition of fenced herd, 1902-15

4 Presumed age and sex composition, fenced herd, 1903-10

5 Presumed age classes of male bison on the range, 1921

6 Distribution of the present population, 1969

7 Comparative distribution of bulls wintering apart from mixed groups

8 Opportunities to see bison from present park roads

9 Number of cows and calves removed during reductions

10 Comparison of female pregnancy rates, by age classes, 1940-41 and 1964-66

1 1 Summary of reproductive data and fetal sex ratios, 1931-32 through 1964-66

12 Comparison of winter climatic factors in Wood Buffalo and Yellowstone National parks

13 Age classes of bison trapped, reductions of 1964-66

14 Calf percentages of mixed herd numbers in spring

15 Calf percentages of pooled mixed herd numbers throughout the year

16 Comparative summary of movements shown by the present wintering populations

17 Food habits as indicated by rumen sample analysis

18 Presence of factors which may affect suitability of habitat for wintering mixed herd groups

1 Introduction

The bison of Yellowstone na- 1963 to provide basic data on the tional park are unique among life history, habits, and ecology of bison herds in the United States, bison in the park. This study re- being descendants, in part, of the port, based on extensive field work only continuously wild herd in this and supplemented by an intensive country. They are today a hybrid search for historical information, herd, being a mixture of the plains provides a basis for management bison (Bison bison bison Lin- and for evaluation of the impor- naeus), introduced into Yellow- tance of this particular bison pop- stone National Park in 1902, and ulation. As a source of interpretive mountain or wood bison (Bison information for the many people bison athabascae Rhoads), which who visit the park, the report may originally inhabited the Yellow- make the bison less of a myth, but stone and surrounding country. a far more interesting reality. They are a wild population, unre- stricted by either internal or boundary fences, and subject to Methods minimal interference by man. Information on numbers, com- Although members of a species position of groups, distribution, which nearly became extinct, and a and habits was obtained by using species of great historical interest, fixed-wing aircraft and helicopter Yellowstone's bison have not been flights, horse and ski travel, and objects of extensive research. limited vehicle use. No set pattern McHugh (1958) studied behavior of route and interval was estab- of bison in Yellowstone. Rush lished; work was scheduled ac- (1932a), Tunnicliff and Marsh cording to season, general animal (1935), and Locker (1953) pub- location, and distances involved. lished information on parasites Time of day was generally not a and disease. Cahalane (1944) factor. A monocular and a varia- summarized the history of the in- ble-power spotting scope were troduced herd and management used for observation. practices as of that date. Age and sex information was The present study was begun in compiled at herd-reduction opera-

521-650 O - 73 - 2 —

2 Bison of Yellowstone National Park tions at Lamar in the northeast ble. Forty-four individuals (30 of quarter (Crystal trap) and on the them females) were neckbanded, Firehole River nearly 35 miles half at each trap. Seventeen fe- southwest of Lamar (Nez Perce males and two males were young trap) during the winters of 1964- adults and older. Half of the neck- 65 and 1965-66. Reductions have bands were lost during the first been held in the park at intervals year. More males than females lost since 1932, primarily to keep the neckbands. Attempts to neckband bison population at numbers sug- animals through use of field im- gested by range condition reports mobilization techniques were not and surveys (Rush 1932b; Grimm satisfactory. 1939; Kittams 1947-58, 1949; Soil During slaughter operations, Conservation Service 1963, 1964). approximately 47% of the animals For reductions after 1960, animals removed from the park were ex- have usually been driven into the amined for pregnancy, abnormali- two above-mentioned large live ties, and evidence of injury or dis- traps by coordinated herding ef- ease other than brucellosis. Re- forts of two helicopters. Squeeze productive tracts could not be chutes permitted handling of most examined, nor fetal sex ratios de- individuals, after which the bison termined because approximately were released or were trucked to a half of removed animals had bru- local slaughterhouse. Animals cellosis or were suspect. Depart- were selected for slaughter on the ment of Agriculture veterinarians basis of brucellosis infection. Un- advised against examination of infected animals were also taken to reproductive organs, where the fill removal quotas. All animals Brucella organism most often lo- were permanently metal ear- calizes, to avoid contamination of tagged during brucellosis testing, slaughterhouse premises and ex- and marked with temporary back- posure of personnel to the disease. tags, which were visible even from Lower jaws were collected for age an airplane. Most were aged by verification using the techniques Department of Agriculture veteri- of Fuller (1959). narians and weighed. Food-habit information came During both winters, some re- from analysis of 22 rumen samples leased animals were marked with collected from animals shot in the color-coded neckbands for area park at all seasons and in various and individual recognition, and locations. Percent composition of for the year of banding. Animals samples was determined by vol- preferably females, yearlings and ume after separation and identifi- older—were chosen a few at a time cation of materials. The analyses on different trap days to distrib- were supplemented by general ute marked animals among re- field observations of animal feed- leased groups as much as possi- ing behavior. 2 The Study Area

The study area included all unmarked by abrupt changes in

parts of Yellowstone National Park terrain. Most of the study area lies

regularly used by the bison popu- east of the divide, and is drained lation, or frequented by them in by the headwaters of the Madison

the past 20-25 years (Fig. 1). The and Yellowstone rivers. Tributar- occupied bison range covers near- ies of the Snake River drain the ly half of Yellowstone's 3472 southwestern corner.

square miles, extending diagonally Park geology is discussed by across the park from the northeast Hague ( 1 899), whose work was fol- quarter to the southwest quarter. lowed by numerous topical stud-

Some phases of study effort were ies. U.S. Geological Survey person- emphasized in the northeast nel are now completing a compre- quarter. Lands outside the bound- hensive research program which

aries are not used to any extent by will add much to present knowl- the park bison, and hence were edge of the complex geologic his- not part of the study area, but they tory of Yellowstone. Extensive vol- are discussed where pertinent to canism, of which the widely dis-

historical populations. tributed thermal activity is a remnant stage, has shaped many of the physiographic features. Effects of Physiography glaciers, which may have persisted as recently as 8000 years ago, are

Much of the park is plateau-like, evident throughout the park. varying in elevation from about The study area was subdivided 7000 to 8000 feet, and cut by large into nine regions. From northeast

and small stream valleys (Fig. 2). to southwest these are: Lamar, Mountains project above the gen- Upper Lamar, Mirror Plateau, eral level on all sides, but are less Pelican, Hayden Valley, Firehole, extensive in the interior. The Con- Madison Plateau, Pitchstone Pla-

tinental Divide traverses the park teau, and Bechler (Fig. 1). The

from west to southeast, generally Lamar (Fig. 3), at approximately

3 4 Bison of Yellowstone National Park

Fig. 1. Map of Yellowstone National Park showing study area.

6400 feet, includes lower Hellroar- above Soda Butte Creek, together ing and Slough creeks, the main with the ridges and tributaries ris- Lamar River Valley below Soda ing eastward to the Absaroka Butte Creek, the north-facing low- Mountains, at more than 10,000 er slopes of Specimen Ridge, and feet Fig. 4). The Mirror Plateau, the Soda Butte area. The Upper including much of Specimen Lamar refers to the Lamar River Ridge, lies between the Lamar The Study Area 5

Fig. 2. Aerial view of a part of the forested plateau, located centrally.

River to the north and east, the refers to all three major geyser Yellowstone River to the west, and basins along that river, together Pelican Valley to the south. Pelican with Nez Perce, Spruce, Sentinel,

Valley (Fig. 5), at 7800 feet, refers and Fairy creeks (Fig. 7). West of to the main valley from the lowest the Firehole, the Madison Plateau portions of Raven Creek to the rises gradually to the Continental mouth of Pelican Creek and in- Divide and extends to the Bechler cludes Marv Bay on Yellowstone Meadows. The Pitchstone Plateau Lake. Hayden Valley, elevation (Fig. 8) lies southeast of the Madi-

7700 feet, is centrally located in son Plateau. The Bechler Mead- the park (Fig. 6). It extends from ows, at6400feet,arecomparableto the Grand Canyon of the Yellow- the Lamar in elevation. stone south to the Mud Volcano, Soils vary greatly. Generally,

west to Mary Mountain, and in- there are deep silts in the bottoms cludes Beach and Dryad lakes to of the big valleys. Morainal materi- the south and Cygnet Lakes to the als are especially prominent in north. The Firehole, at 7200 feet, Lamar. Lake deposits of clays and 6 Bison of Yellowstone National Park

Fig. 4. The upper Lamar drainage with the edge of the Mirror Plateau to the right, a part of the Absaroka Mountains in the background. The Study Area 7

Fig. 5. Bison on the Pelican Valley winter range.

Fig. 6. A part of the Hayden Valley winter range with Alum Creek in the foreground. 8 Bison of Yellowstone National Park

Fig. 7. The Lower Geyser Basin area of the Firehole winter range in early spring.

sands are found in Pelican and month, averaged 18. 0°F; July, with Hayden valleys. Higher areas a mean of 62.8°F, was the warmest. commonly have shallow, poorly Temperatures at this station aver- developed soils derived from vol- age about 5°F higher than those canic parent material interspersed for most of the park. with alluvial sites. The same summary indicated that average annual precipitation in the study area varied from Climate 13.73 inches at Lamar to 38.26 inches at Bechler. Near Pelican, Throughout the area winters the annual average was 19.00 inch- are long and cold, with short cool es. Most precipitation occurred as summers. The U.S. Department of snow. For most of the park, be- Commerce Weather Bureau tween the 7000- and 8500-foot (1930-59) summary for Yellow- levels, the average snowfall was stone National Park indicated for about 150 inches, with Lamar av- the headquarters' station at eraging 85-95 inches, and Lake, Mammoth, near the north bound- near Pelican, averaging 146 inch- ary, a mean annual temperature of es. For a 50-year period at Lake, a 39.8°F. January, the coldest range in snowfall of 81-270 inches The Study Area 9

is recorded. Actual depth on the highest elevations. Summer began ground at Lake, as recorded by 1 July in the valleys, late July in the snow survey measurements (U.S. mountains. Killing frosts are usual Department of Agriculture— Soil in most locations before the end of

Conservation Service, 1919-67), August, so fall extended from 1 averaged about 19 inches for 1 September to mid-November in all January and about 35 inches by 1 areas. At higher elevations, snow April. Lamar would usually have depth was often considerable by somewhat less; Bechler, somewhat early November. more. Crusting conditions, for which no record is available, varied considerably. Vegetation Seasons of the year vary with location and altitude. Warm sites Vegetation types were not near thermal activity are snow-free mapped for purposes of this earlier and have a longer growing study. Figure 1 indicates the ex- season than surrounding areas. tent of the larger meadows within Winter extended from mid-No- the forested parts of the study vember to mid-April in all areas of area. More detail is apparent in the study. Spring began in mid- Figs. 30 and 31, which show subu- April in Lamar, in mid-May in the nits of the study area. Major spe- higher valleys, and on 1 July at the cies of plants, according to site, are

Fig. 8. Summer range on the western part of the Pitchstone Plateau. 10 Bison of Yellowstone National Park listed in Table 1. General descrip- are scattered throughout the for- tions of park vegetation are est on moist sites along streams provided by Bailey (1930), Bailey and around ponds, and appear as and Bailey (1949), and McDougall small openings in drier locations. and Baggley (1956). Common and Particularly on the Mirror Plateau, scientific names used are listed in boggy side hills with dense sedge Appendix I. These follow Booth growth are numerous. (1950) or Booth and Wright On the upper plateau levels and (1959). mountain slopes, subalpine mead- The large, open valleys of La- ows are found. Above these, at the mar, Pelican, Hayden, and Fire- highest elevations, alpine vegeta- hole have dense sedge growth tion occurs to a limited extent. bordering the streams and extending across the flat bottoms. The slightly higher slopes and levels History support bunchgrasses, forbs, and sagebrush, with scattered marshy Yellowstone National Park was swale areas. Shrubs, except sage- established in 1872, before the brush, are of limited extent gener- surrounding area became the ally in these valleys. In Lamar, wil- states of Idaho, Montana, and low was grubbed out in some Wyoming. Boundary changes, places to increase the area of pas- made twice, added small areas to ture and hay land during early the original rectangle and altered Buffalo Ranch operations. Exten- the east boundary in 1929 to con- sive grassland and sagebrush areas form for most of its length to the on high slopes and ridges are par- drainage divide formed by the ticularly common in the northeast Absaroka Mountains. Most of the quarter, although patches of more land adjacent to the boundary is lush herbaceous vegetation are administered by the U.S. Forest frequent. Service.

Much of the study area is forest- Haines (1963) summarizes the ed, predominantly by lodgepole history of man's occupation of the pine, which varies from dense, Yellowstone Plateau. Prehistoric even-age growth with little under- hunters and gatherers used the story to open stands with consider- area extensively. Members of sev- able sedge and grass. Dense shrub- eral tribes of modern Indians were by undergrowth is usually not ex- primarily summer hunters, al- tensive. Down timber is common. though a few sheep-eaters lived a At higher elevations, Engelmann marginal existence throughout the spruce and alpine fir replace the year. Hostile Indians did not travel lodgepole. Whitebark pine is the park after the Bannock War of found in some locations. Meadows 1878, but hunting parties from The Study Area 1

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5-1 I a 8 > D 12 Bison of Yellowstone National Park reservations were known at the 1887 official regulations permitted park fringes as late as 1893 hunting while traveling in the (Hough 1894). Although few left park. Legal means for enforcing written accounts, trappers, begin- regulations were lacking, although ning with John Colter in 1807, vis- the Army troops stationed in the ited the area many times before park after 1886 did what they the end of the fur trade in 1840. could. Attempts at protection had Miners and explorers followed. limited effect until passage of the The park was not subject to set- Lacey Act in 1894 provided legal tlement, and there were few peo- machinery and jurisdictional au- ple for some years after its estab- thority for dealing with violators. lishment. With the exception of a Outside the park, ineffective laws few early squatters, developments contributed to poaching within the were for administrative use or boundaries. concessioner operation. In con- Not until 1901 did the Superin- junction with these, horses and tendent of the park believe the cattle were grazed in some places, laws of all three surrounding states and wild hay was cut. Disturbance were such that the wild bison left was generally minimal except in in Yellowstone might be effectively the Lamar area. Skinner and Al- protected, but their numbers were corn (1942-51) summarize the so few that survival seemed doubt- Buffalo Ranch-Lamar Ranger Sta- ful. Intensive management of an tion operations of Lamar and introduced herd began in 1902 to Slough Creek valleys from 1907 ensure survival of some bison in through 1951. Seeding and irriga- Yellowstone. For a time the ani- tion practices were part of the hay- mals lived in semidomestication, ing program, as well as construc- and were fed hay and tended al- tion of buildings, fences, and other most like a herd of cattle. Manage- necessities of a ranch. ment policy gradually changed to During the early years of the one of minimal interference by park, wildlife had little protection. man, which continues in spite of The Act establishing Yellowstone the impact of steadily increasing National Park provided only that numbers of tourists. The present wildlife should not be "wantonly (1970) bison population is com- destroyed" nor subject to "capture pletely wild and unfettered by and destruction for the purposes fencing or artificial management. of merchandise or profit." Until 3 The Bison Population

The Historic Population

The genus Bison probably in- Yellowstone National Park (Pattie vaded North America during the and Verbeek 1967). In 1964 a fos- later part of the early Pleistocene. sil cranium (B. b. athabascae) was The bison occupying the continent found embedded in a natural oil in historic times were descendants seep on the Mirror Plateau in the of a second migration of Bison park. from Eurasia, which crossed the The Yellowstone bison of histor- Bering Straits at the start of the ic times were a remnant of a once late Pleistocene according to Skin- much more extensive bison popu- ner and Kaisen (1947). Of the in- lation, known to trappers and In- vading species, only one persisted dians, which inhabited the moun- to give rise to B. occidentalis, the tain ranges and the intermountain ancestor of B. bison, the modern valleys of the Rockies and extend- form. Two subspecies, B. b. bison ed on west into Washington and and B. b. athabascae, are recog- Oregon. Most of these bison were nized by cranial evidence, al- gone by the 1840s (Aubrey Haines though historical accounts suggest 1968 pers. comm.). According to there may have been others (Roe the distribution map of Skinner

1951). The form athabascae is and Kaisen (1947), these were apparently the more primitive of mountain bison. Considerable the two subspecies (Skinner and numbers of bison once lived close Kaisen 1947). to the park. Many skulls have been Just when bison first reached the found in the Red Rock Lakes area,

Yellowstone plateau is not known, approximately 35 miles west of but modern bison inhabited the Yellowstone (Owen Vivion 1968 area before historic times, perhaps pers. comm.) Frank Childs, for- before the most recent period of mer Yellowstone ranger who intermountain glaciation. Bone worked on Red Rocks land acquisi- fragments from bulls, cows, and tion matters during the mid- calves (B. bison) were found near 1980s, heard that 300 bison died the edge of a glacier northeast of there during a bad winter many

13 14 Bison of Yellowstone National Park years earlier (1965 pers. comm.). tions, often at a season when biting Many skulls have also been taken insects may have driven the game from the Mud Lake area of Idaho, from the lower elevations of passes approximately 55 miles southwest to adjacent higher slopes and of Yellowstone (Richard Wilson ridges. Finally, the few early trav- 1968 pers. comm.). Osborne Rus- elers who wrote of their journeys, sell, writing in 1835, mentions the including official government par- large numbers of buffalo (bison) ties, often commented only on seen in both the Red Rock and wildlife which was actually sought Mud Lake areas (Haines 1955). out or shot for food. Doane (1876) comments that "buf- —falo skulls are strewn by thousands " in the Yellowstone valley about Mountain Bison 40 miles north of the park. Ac- counts of wild bison adjacent to The existence of mountain bi- and within the park, dating from son, different in appearance and 1860 through 1902 (Appendix II), behavior from the plains type and leave no doubt that substantial gone from much of their range by numbers of bison inhabited the the 1840s, has generally been little Yellowstone Plateau at all seasons, known. Christman (1971) reviews and long before the killing of the historical evidence for the subspe- northern herd of Great Plains bi- cies, their distribution to the west son in the early 1880s. of the plains type, and reasons for A misconception of some writers their early disappearance. He be- —that Yellowstone's bison of his- lieves the Indians' acquisition of toric times were displaced survi- the horse was the factor underly- vors from the Great Plains slaugh- ing the extermination of mountain ter—probably stems from: (1) the bison from extensive areas of orig- lack of recognition of two subspe- inal range, particularly in Wash- cies of Bison bison; and (2) the ington, Oregon, and Idaho. impression that early explorers Many early references to Yel- found little "game" in the Rocky lowstone bison use the term Mountains. Three factors contrib- "wood" or more commonly ute to the idea that bison were "mountain" bison or buffalo (Fig. sparse in the mountains. Com- 9); some of the characteristics of pared to the abundance of certain the race were recognized by a large mammals on the plains, the number of early travelers and ob- mountains probably seemed al- servers. Historical accounts gener- most uninhabited. Secondly, travel ally agree that, compared with the routes followed river valleys and plains bison, these mountain ani- drainages, crossing small areas of mals were more hardy, fleet, and high summer range at few loca- wary, and had darker, finer, curl- The Bison Population 15

Fig. 9. Cows and calves photographed in a remote part of Hayden Valley sometime before 1894. These bison were frequently called mountain bison by early observers. Photo by John Folsom, a winterkeeper at Canyon.

ier hair. Sex and age differences Blackmore (1872) was informed among animals seen may account that the mountain buffalo con- for discrepancies in description of gregated usually in bands of 5-30, size. The geologist Arnold Hague rarely more. Other observers (1893) provides the following: agree that the bands were small, The Park buffalo may all be classed and the animals quite wary. Super- under the of mountain buffalo head intendent Norris described them and even in this elevated region they as "most keen of scent and difficult live for the greater part of the year in of approach of all mountain ani- the timber. . . .most unusual, save in midwinter, to find them in open val- mals" (Superintendent of the Yel- ley or on the treeless mountain slope. lowstone National Park 1880). They haunt the most inaccessible and Altitudinal migrations were an-

out-of-the-way places, . . . living in other characteristic of mountain open glades and pastures, the oases of bison (Christman 1971). Historical the dense forest, . . . the rapidity of their disappearance on being accounts from Yellowstone also alarmed. It is surprising how few suggest this habit. Superintendent buffalo have been seen in midsum- Norris, in his annual report of mer, even by those most familiar with 1880, describes summer and win- their haunts and habits. They wander ter distributions of bison in the about in small bands. . . . 16 Bison of Yellowstone National Park park, stating clearly: by limited cranial evidence. Skin- ner and Kaisen (1947) show an

. . .summer in the valleys of the overlap in general distribution Crevice, Hellroaring, and Slough Creeks, and the mountain spurs be- between mountain and plains bi- tween them, descending with the in- son along^ the east slopes of the

creasing snows, to winter . . .East Rockies, including Yellowstone,

Fork [Lamar]. . .and as the snows but state that ranges for historic

melt . . .returning to their old times must be based on early ac- haunts. counts plus occasional bones or The historical accounts of dates crania. Seven skulls from Yellow- and locations of bison (Appendix stone's original wild herd were II) collectively also show a repeti- picked up on the ground along the tive pattern of seasonal bison dis- Gardner River and at Mammoth tribution which reflects altitudinal in 1902. All had weathered sur- movements. faces. These were considered as Historical accounts recognizing most likely representing athabas- a mountain buffalo are supported cae. The 1964 skull (Fig." 10) found

Fig. 10. Skulls of Bison bison athabascae (left) and B. b. bison from the Mirror Plateau, Yellowstone National Park. Photo by David Love, U.S. Geological Survey. The Bison Population 17

on the Mirror Plateau was identi- Table 2 also shows the decline of fied by Skinner (1965) as "an ex- the population to an actual count ceptionally long horned, appar- of 23 in 1902. Again—considering ently young Mountain bison = B. habits, behavior, and census diffi- (B.)b. athabascae " No Yellow- culties—the population probably stone skulls which predate the was higher; perhaps 40-50 moun- 1902 introduction have been iden- tain bison survived. The near-ex- tified as plains type. tinction in about 25 years was the result, initially, of sport and table hunting on both sides of the park Numbers and boundary, plus market hunting, particularly in the Lamar, by both Distribution through 1902 the park hotel construction crews and the Cooke City miners. The Numbers and distributions from capture of calves by local ranchers the historical accounts of Appen- interested in starting private herds probably most prevalent in dix II are shown in Table 2. Norris was (Superintendent of the Yellow- Lamar and the west-side wintering stone National Park 1880) estimat- areas. Finally, as bison everywhere extinction, the price ed a total of 600, dividing the verged on population into three herds ac- paid for heads, plus the minor cording to area. By this date, penalties if caught, attracted killed all poaching had certainly begun in- poachers who ages and side the park, along with increas- both sexes in the wintering areas. ing pressure on an ever-shrinking Known losses as listed do not re- mountain bison population out- flect the extent of the kill. Al- side. Numbers in a given area fluc- though the Howell poaching case tuated then as now. After consid- resulted in passage of the Lacey eration of all the listed reports of Act in 1894, the population de- numbers and distribution, the his- clined further as poaching, prima- torical population, ranging in part rily from the west side, continued. losses, beyond the park boundaries, is es- Natural coupled with scat- timated to have been perhaps tering of the few remaining ani- 1000 animals. This seems reasona- mals, left a minimal breeding ble when bison habits and behav- population in the most remote ior and difficulties of making places of the Pelican-Mirror-Up- counts are all considered. Subesti- per Lamar country. mates by area and season are at the The distribution, to the extent bottom of Table 2. They are made known, of the original population to provide a reference point and was similar to the present distribu- must be considered educated tion, but larger numbers used cer- guesses. tain areas more extensively and

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The Bison Population 23 ranged beyond the park bounda- the Madison Plateau in summer. ries part of the time. Figure 1 People, traveling perhaps when shows the probable general distri- the bands were south of the main bution and population movements valley in the forested areas, may of mixed herd groups. The term rarely have seen a group. Hague's "mixed group," as in Fuller (1960), (1893) reference to the borders of is used here also for groups which Elephant Back (south of Hayden usually contain some mature bulls Valley) as summer range suggests as well as cows and young. Four that bison did regularly summer in areas of summer range and five of the area. Perhaps it was the least winter range are indicated. In two important summer range. locations the population probably Large numbers of bison regular- moved across present boundary ly wintered in Lamar, Pelican, and lines in numbers. Hayden valleys (Fig. 12). The Fire-

From northeast to southwest, hole seems to have been less im- the four areas of historic summer portant. Snow conditions common range were: north of Lamar, Up- in the Bechler Meadows make it per Lamar-Mirror Plateau, Hay- unlikely that large numbers habit- den Valley, and Madison-Pitch- ually wintered there, but certainly stone plateaus. Large numbers of small groups must have since bison apparently ranged at least calves were captured there in early three of the four areas. North of spring (Murri 1968). Lamar, the summering herds of Historical reports do not indi- the northern part of the Absaroka cate groups along the Madison and Range split south to the Lamar Gallatin rivers to the northwest, Valley and north beyond the park within the park, but Raynolds to other valleys to winter. On the (1867), while crossing from Hen- west side, the greater part of the ry's Lake to the Madison River, summering herds of the Madison- just west of the park, in 1860 Pitchstone plateaus probably reported bison "among the ." moved southwest beyond the park hills, . . Small groups of bison, toward the east end of the Snake also unreported, may have used River plains (Mud Lake area) as the large grasslands just north of Norris presumed (Superintendent the Madison River (south of Cou- of the Yellowstone National Park gar Creek) as they did in the 1880). Historically, as now, the 1950s. Upper Lamar-Mirror Plateau was Knowledge of travel routes used used extensively. The importance by people during the early days of of Hayden Valley as historic sum- the park, which probably followed mer range is less clear. Some of the main game trails, suggests relative bison which wintered in Hayden game population numbers, loca-

Valley apparently moved west to tions, and movements (Fig. 11). 24 Bison of Yellowstone National Park

Fig. 11. Map of general distribution and movements of bison mixed herd groups in historic times. Fig. 12. Bison wintering in Hayden Valley prior to 1894. Photo probably by John Fol- som, early Canyon winterkeeper.

Hague (1893) mentions the lack of patrols on the Madison Plateau buffalo trails, but he was compar- further support early reports of ing Yellowstone to the plains. size and distribution of a large Definite buffalo trails did exist west-side summering population (DeLacy 1876). Norris' (Superin- which may have extended north tendent of the Yellowstone Na- across the Madison River. tional Park 1880) map shows a trail northeast across the Mirror Pla- Finally, scattered individuals, teau which follows the route of probably bulls, must occasionally, present buffalo trails. The usual then as now, have been found in Pelican-Upper Lamar route (in peripheral areas. Although early part an elk trail) once crossed reports of live bison are lacking, Lovely Pass between Raven and some animals must surely have Mist creeks (Superintendent of the inhabited places in the northwest Yellowstone National Park 1897). quarter of the park outside the Movement of bison across the known or presumed distribution Mary Mountain route between of herd groups. In the southeast, Hayden Valley and the Firehole, Holt (1899) recorded a buffalo in commonly used by people prior to the Thorofare area. A skull from construction of a road along Yel- Two Ocean Pass (Fryxell 1926) lowstone Lake, was implied by ear- just south of the boundary, found lier writers, and stated as fact by before 1925, presumably belonged Hough in 1894. Routes in use by to another such individual. 26 Bison of Yellowstone National Park

The Present Population ently never joined the wild bison. Origins Twenty bulls from the Buffalo Ranch were driven 14 miles up the

As stated previously, the Yellow- Lamar River in 1914; these all re- stone bison of the present derive turned. from two subspecies: plains bison Members of two other small from Montana (Pablo-Allard herd) groups of semidomestic bison, and Texas (Goodnight herd), in- those of the Yellowstone Lake troduced in 1902, and a remnant Boat Co. and some from Henry's of the original wild population of Lake west of the park, never mountain bison. Skinner and Al- mixed with the wild herd corn (1942-51) summarize the in- (Appendix III). troduction, numbers, and subse- In spite of very low numbers quent management practices per- and a pessimistic outlook, the orig- taining to the introduced herd at inal wild herd did persist, and the Buffalo Ranch in Lamar. Pop- gradually increased once protec- ulation numbers are from that tion from poaching was assured. source and other official reports. The critical survival period ex- 7 Skinner also provides a resume of tended from 1902 until about official information concerning the 1920; thereafter, groups of bison wild bison, but does not attempt to which did not frequent the Buffalo evaluate the question of their sur- Ranch were more common. These vival. Information scattered in the probably contained escapees from diaries, reports, and correspond- the introduced herd as well as na- ence of park personnel (Yellow- tive animals. Table 2, from sources stone National Park Archives) pro- listed in Appendix III, shows vides the basis for the following. dates, locations, and numbers for Before 1915, introduced bison the wild herd from 1903-15. Later of plains stock could not have es- official estimates of wild herd caped to form a wild group. The numbers are not used, since there introduced herd was in a small was some possibility of wild and fenced pasture at Mammoth from introduced animals intermingling 1902 until moved to the Buffalo after 1915. The table shows clearly Ranch at Lamar in 1907. From the presence of a remnant wild 1907 until at least 1915, these herd in Pelican Valley in winter, animals were closely day-herded, and on the Mirror Plateau in and apparently put in a fenced summer, as well as a few individu- pasture at night. Although one als elsewhere. There was a steady plains bull from the fenced herd increase, indicated both by calves was turned out in 1903, and one or and by total bison seen. The two stray bulls were mentioned known population more than later in scout reports, these appar- doubled between 1903 and 1912. The Bison Population 27

An actual count was difficult, as Present composition Nowlin (1912) of the Biological Survey found: "I have never seen An estimate of the contribution buffaloes on the range so wary and of the two subspecies to the pre-

difficult to locate as the wild ones sent population gene pool is, at

in the Yellowstone Park." best, rough but is preferable to Official population estimates of having none. Table 3 shows the the time did not allow for more sex and adult-calf composition of animals than were actually seen; the fenced herd from 1902 they were undoubtedly conserva- through 1915. The addition to this tive. By 1912, as Nowlin's classifi- herd of four calves captured by cation of 35 animals shows, the Army scouts (Fig. 13) from the survival of calves (8) and yearlings wild herd for the purpose of add-

(7) was encouraging, and the po- ing a second bloodline is also tential for increase (13 females) shown. From these numbers, Ta- was apparent. By 1915, the popu- ble 4 was compiled to show the age lation may have been nearing 100. classes according to sex. The bulls Known mortality is shown only in 4 years and older were assumed to 1904. While winter loss probably have done the breeding in this occurred during other years, the fenced situation, although young- death of many animals would er bulls may have been physically surely have been observed and capable. Females were assumed to reported by Army patrols or breed as 2-year-olds and to calve at scouts. 3. From these assumptions and the

Fig. 13. Buffalo Jones and Army Scout Holt with a captured bison calf on a sled. Photo from Yellowstone National Park files. 1

28 Bison of Yellowstone National Park

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3 £ CM CO if) lO oo CD O CM CO »f> « o o o o o o O o o ed J3 CD cd cd CD cd cd CD CD CD CD CD CD CD 4»ip The Bison Population 29 tables, the wild strain in the fenced point), castration of bull calves group was estimated at a maxi- averaged slightly over 50% from mum of 10% by 1910. Further di- 1916 through 1931. As a result, lution of the wild strain in the the number of aggressive, domi- fenced herd was assumed until nant plains-type bulls with the in- perhaps 1917. termingled groups would have Sometime between 1915 and been considerably decreased. 1920, intermingling of the intro- Table 5 shows the presumed duced and wild animals began. At numbers of freeranging males in first this was probably gradual. various age classes for both wild Park records do not show the spe- and introduced herds in 1921. An cific year, but after 1915 the close estimated 40% of the bulls older herding practices in use with the than 5 years were of the mountain introduced herd were abandoned, bison strain. Their contribution to and the animals were kept on open the breeding activity may have range all summer. Close account been larger, as discussed above, was kept of most of them for sev- than their numbers indicate. eral more years, but there were The trend toward increased some escapees. After 1921, with mountain bison strain would have construction of a log drift fence continued during the 1920s. On across the Lamar Valley above this basis, a reasonable estimate of Soda Butte Creek, deliberate ef- wild strain in the present bison forts were made to keep the intro- population would seem to be 30- duced herd on the higher summer 40%. ranges, where intermingling with the wild bison must have quickly and distribution increased. Numbers After intermingling of wild and introduced animals began, several Management practices for many factors tended to increase the wild years made little attempt to re-cre- strain in the total population, al- ate a natural, wild bison popula- though the plains type outnum- tion in the park. Efforts concen- bered the wild roughly 3:1 about trated on ensuring bison in num- 1917, and perhaps 4:1 in 1921. bers sufficient to guarantee perpe- The number of males in the intro- tuation. Through 1938, horseback duced herd was reduced by the riders rounded up as many bison yearly segregation of a show herd as possible in late fall and drove of bulls beginning in 1909. Addi- them into the Lamar Valley for tional bulls were removed by live feeding and reductions. To cut shipment and slaughter. To fur- population numbers to desired ther reduce the male surplus levels during these reductions (from a ranch operation view- (and in most later ones), cripples, 30 Bison of Yellowstone National Park

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TABLE 5. Presumed age classes of male bison on the range, 1921.

Tn1"rr*Hiir'fk H hprrl Age classes wiiQ neru 1I1LI UUULA U llvl U

7 1 21

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Total males 1 a year and older 51 198

Total population 125 estimated 526

An equal sex ratio is assumed. aNumber includes 96 steers among the 1-5 year olds. aged animals, and those infected not occur, although a 1946 file with brucellosis or otherwise con- report contains a penciled nota- sidered undesirable were removed tion of some bison in Hayden Val- to improve the herd, in keeping ley in 1930-31. with the ranching viewpoint (W.S. Chapman 1969 pers. comm.). In In 1936, animals were trucked 1939, a hay-baiting operation was to the Firehole and Hayden valleys substituted for the roundup. Hay for release. They were thought to was fed to some extent every win- have formed separate herds, but ter through 1952. Before 1936, as numbers increased, some move- most animals wintered in Lamar, ment between the two valleys be- with some in Pelican. During came obvious, and they were summer, bison concentrated on called the Mary Mountain herd. the Mirror Plateau and Upper Two other herds were distin- Lamar, with scattered bulls and a guished, on the basis of wintering few small groups to the north. In areas, as the Lamar and Pelican. spite of very large populations None of these herds is geographi- wintering in Lamar, natural rees- cally isolated at all seasons of the tablishment of the population west year, but the names are still used beyond the Pelican area into Hay- to designate the wintering popula- den Valley and the Firehole did tions. 32 Bison of Yellowstone National Park

Population counts, estimates, and 1932, before Rush recommended known losses (mainly reductions) a maximum of 1000. Later deci- are listed in Appendix IV by the sions lowered the maximum num- three wintering populations and as ber until frequent reductions had park totals. Aerial counts were cut Lamar herd numbers to a started for the four main winter- count of 143 in 1952. After an aer-

ing valleys (Lamar, Pelican, Hay- ial count for all main wintering den Valley, Firehole) in 1949. valleys totaled 1477 in January These counts were not made every 1954, reductions were made on all year, nor were all main areas population segments. An aerial checked each time. Usually no at- count for the entire park of 397, tempt was made to count scattered made in March 1967, was consid- animals in fringe areas, nor to ered very accurate. Thus, the check the Bechler Meadows before park population of bison for most 1965 (Jim Stradley 1968 pers. of the study period was lower than comm.). When aerial counts were at any time since the early years of not available, winter ground the introduced herd. counts were made. Estimates Winter and summer distribu- based on previous counts, reductions for mixed herd groups and tion figures, and presumed in- separate bulls at population levels creases were made by park person- of the study period are shown in nel when counts were not availa- Table 6. Divisions between major ble. Because of possible popula- areas indicate geographic separation shifts, these may be unrelia- tion but do not imply population ble. Population numbers are for isolation. Bulls were found in all winter seasons, after reductions, areas of herd use and also were but before calving. scattered in places where herd Bison increased steadily after groups were seldom or never seen. 1902 until, with a gradual change Past records indicate that mixed in policy about 1930 from one of herd groups used some of these ranching to one of preservation of areas when population numbers bison in a natural state, the Na- were higher. In effect, places most tional Park Service decided to cut frequented by mixed herd groups the numbers wintering in Lamar. probably represent core areas or The decision was based on the population centers from which gradual elimination of artificial bulls and mixed herd groups management practices and sup- move into less-favored locations as ported by information derived the population increases. from a range-condition and carry- Although Firehole and Hayden ing-capacity study (Rush 1932b). valleys are combined as the Mary Lamar-wintering bison numbered Mountain area, winter distribution over 1000 from 1929 through of total numbers and mixed herd The Bison Population 33 groups favored Hayden Valley, 50 ranged from the Little Firehole according to available counts Meadows to the Pitchstone Pla- since the 1950s. During the reduc- teau. In spite of more reductions, tions of 1964-65 and 1965-66, small mixed herd groups were animals were herded from Hay- seen during the summers of 1965, den Valley to the Nez Perce trap 1966, and 1967. on the Firehole side with helicop- After the early 1900s, animals ters, but a prereduction count in were not again reported wintering December 1964 showed 436 bison in the Bechler Meadows southwest in Hayden Valley, and only 54 on of the Madison Plateau until Feb- the Firehole. Prereduction counts ruary 1955, when three bulls were of 1965-66 also located most ani- seen just outside the park. An oc- mals in Hayden Valley. Groups casional bull may have wintered in released from the trap usually the meadows earlier, since a few remained on the west side the rest animals again began to summer on of the winter, but movements by the Madison Plateau in 1939. Ob- them between the two wintering servations and reports indicate a valleys were known for all seasons. few animals in that area nearly Groups were seen only in the two every winter since the mid-1950s, main valleys and the intervening in spite of considerable decrease in Nez Perce Creek drainage during the Mary Mountain herd, from the study period, but a group of which these animals probably 20-23 was seen at Beach or Dryad came. No mixed herd groups were lakes, 5 miles south of Hayden reported wintering in the Bechler Valley, the winter of 1955-56 (Jim Meadows until 1962-63, but the

Stradley 1968 pers. comm.). area is seldom visited in winter. Periodic plane flights begun in The majority of the wintering March 1965 showed a small group mixed herd groups of the Mary there in 1964-65 and 1965-66. Mountain area summered in Hay- Lamar and Pelican populations den Valley and to the south of it as are isolated from each other dur- far as Beach and Dryad lakes, al- ing most of the winter except for though some animals from the occasional movements of a few same population summered to the hardy bulls. Table 6 shows the val- west of the Firehole. Ranger re- leys as distinct wintering areas. ports indicate that infrequent Groups in Lamar ranged the val- mixed herd use of the Madison ley from Soda Butte west to the Plateau began in 1939, 3 years af- Hellroaring Slopes. In Pelican, ter the bison were released on the group use extended from the Firehole. By the early 1950s, use Mushpots-Mudkettles of Pelican had become common, but appar- Creek downstream to Vermilion ently almost ceased after the 1955 Hot Springs and included the low- reduction. But in 1963 as many as er parts of Astringent Creek and

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llPQ Q, 36 Bison of Yellowstone National Park adjacent hot-spring areas to the near Lake Abundance, just out- west. Although no groups fre- side the northeast corner of the quented Ponuntpa Hot Springs (6 park. miles north of Pelican Valley) dur- Two small areas, separated by ing the study, both historic records distance and topography from the and reports of the mid-1950s (Jim four main valleys, have had small Stradley 1969 pers. comm.) indi- wintering mixed herd groups be- cated some previous mixed herd fore the study period, according to use. recent records. Approximately 40- Bison from both Pelican and 50 bison wintered north of the Lamar Valley wintering popula- Madison River on the flats just tions ranged widely during sum- southwest of the Cougar Creek mers on the Mirror Plateau and patrol cabin in 1955-56. Some the Upper Lamar. Neckband ob- were also seen in 1959. In the An- servations and aerial counts telope Creek basin on the north- showed that the two populations, east flank of Mount Washburn (no except scattered bulls, combined date), 45-70 wintered one year on the east boundary for several (Jim Stradley 1968 pers. comm.). weeks in 1967. Main use areas in There were no summer reports of the Upper Lamar region during groups north of the Madison Riv- the study period were the Cache- er, although the bison wintering Calfee and the Miller Creek ridges there in the 1950s may also have from the east boundary down, and summered there. the series of meadows and parks Bulls were not distributed pro- on the east rim of the Mirror pla- portionately among the four main teau extending from the head of wintering valleys, as shown in Ta- Flint Creek to the heads of Peli- ble 7. Most of the Mary Mountain can-Timothy-Raven creeks. At area bulls wintered in Hayden Val- higher population numbers, as ley. Lamar Valley had more bulls reports of the 1930s and 1950s than did the Pelican area. In indicate, herd-group use included summer, bull distribution was most of Specimen Ridge north and widespread. Animals were so scat- west of Flint Creek as well. tered that preference for certain To the north of Lamar Valley, general areas by a large percent of where at present only bulls sum- the bulls was not observed. mer, past reports indicate small Recent and present population mixed herd groups on the upper distributions generally resemble Slough Creek meadows and the those described by historical Buffalo Plateau (Jim Stradley, sources (Fig. 11). Winter distribu- Dave Pierson 1968 pers. comm.). tions within the park approximate In August 1943, a report was re- those of early times, as do summer ceived of an estimated 150 bison distributions on the Mirror-Upper The Bison Population 37

TABLE 7. Comparative distribution of bulls wintering apart from mixed groups.

Lamar Pelican Hayden Valley Firehole

No. Total % No. Total % No. Total % No. Total % Year bulls pop. Bulls bulls pop. Bulls bulls pop. Bulls bulls pop. Bulls

1965-66 36 66 55 29 100 29

1966-67 48 82 56 28 124 23 89 135 66 15 54 26

1967-68 44 89 54 33 160 19 73 131 56 11 57 19

Lamar. Other summer distribu- became reestablished. Or the in- tions have changed most. The crease may not be real, but may herd which summered north of result from incomplete historical the Lamar-Yellowstone rivers in information. historic times is now gone. The Although present winter distri- large numbers which once ranged butions seem little altered (except the west side (Madison-Pitchstone in total numbers) compared to his- plateaus) in summer are reduced toric times, the Firehole popula- to comparatively few. The seg- tion may be larger now. Changes ments of these two historical in the summering distributions of summer herds which wintered Hayden Valley to the east and the beyond the park boundaries are Madison-Pitchstone plateaus to also gone. The recent Hayden Val- the west may have caused changes ley summering population seems on the Firehole, or unrecorded larger than the historic popula- poaching in that wintering valley tion. Bison use of the valley may may have resulted in apparent ear- actually have increased, compared ly low numbers. to former times, as the population General Characteristics

Physical Characteristics Appearance

Bison are generally dark brown Males and females generally in color, almost black when a new resemble each other in color,

coat is growing in during summer. shape, and presence of permanent The head, forelegs, hump, and horns. Both sexes have the shoul- shoulders are covered with longer der hump (calves do not) which, hair (about 6 inches on shoulders together with the longer hair on and hump), but the hair on the the foreparts and head, give a

flanks and hindquarters is much massive appearance to the front of

shorter (about 1 inch), so that the body compared with the hind- some bison look as though they quarters. Bison are, however, sex- had been clipped (Fig. 14). As the ually dimorphic (different in ap- coat ages, the longer hair over the pearance); older animals can be hump and shoulders may lighten differentiated by an observer (Figs.

considerably, becoming almost tan 19-22). Horn size and shape is on some animals, particularly old- characteristic; additionally, bulls

er bulls. Shedding of old hair be- are larger and the head shape is

gins in spring, but many bison still broader and generally more mas- have ragged patches of lighter- sive. The contrast between areas of

colored, old hair in mid-summer, long and short hair on bulls is particularly on the shoulders (Fig. more marked. 15). Wisps of this crinkly, shedding hair are commonly seen on Weight trees and bushes (Fig. 16). Calves are reddish tan at birth (Fig. 17) but begin to lose this first Weight differences are greatest coat and change to brown-black at between male and female adult

about 3 months (Fig. 18). By about bison. Weights (except adult bulls) 5-6 months of age calves are com- were recorded in Yellowstone dur- pletely dark. The occasional red ing the winters of 1964-65 and

one seen in the fall is a late-born 1965-66, when adults weighed less calf. (indicated by sequential winter

38 General Characteristics 39

Fig. 14. Clipped appearance of a mature bull. Photo by M.D. Beal, Yellowstone Na- tional Park.

weight records) than they would in (Fig. 23) whose skull is still the the fall. Estimates of maximum largest listed in the records of the bull weights of 2000 pounds were Boone and Crockett Club (1964). made by experienced observers. This animal, a member of the Most adult cows weighed between Buffalo Ranch herd (see History) 800 and 1100 pounds. Yearlings was shot in 1925 after he became of both sexes usually weighed be- too dangerous for the semiranch- tween 500 and 700 pounds, calves ing operation of the time. Old (8-9 months old), between 300 and park files indicate he was the off- 400 pounds. Weights at birth have spring of one of the plains bison not been recorded here; Park cows which was pregnant when (1969) gives a range of 30-70 brought to Yellowstone in 1902. pounds. Hence this bull was of plains bison stock, rather than a hybrid off- No record was made of the spring of plains and mountain bi- weight of the Yellowstone bull son. 40 Bison of Yellowstone National Park General Characteristics 41

Fig. 17. Newly-born calves in a mixed herd group. Photo by Verde Watson, Yellow- stone National Park. 42 Bison of Yellowstone National Park

Fig. 18. The calf (5-6 months old) to the left of the cow has lost its first red-brown pelage. Photo by David Condon, Yellowstone Na- tional Park.

Fig. 19. Note head shape and relative size of the cow, left center, compared with the bull at right. Photo by David Condon, Yel- lowstone National Park. General Characteristics

Fig. 20. Spike-horn bull, approximately 2.5 years old. Photo by David Condon, Yellow- stone National Park. 44 Bison of Yellowstone National Park

Fig. 22. The horns of the adult cow (at right) are relatively slender compared with

those of bulls. The spike-horn bull at left is approximately 3.5 years old. Photo by David Condon, Yellowstone National Park. Fig. 23. Old Tex, the Yellowstone bull whose head is still first among record bison heads listed by the Boone and Crockett Club (1964). Photo by James Kimber- lin, Yellowstone National Park. 46 Bison of Yellowstone National Park

Life span summer, groups of more than 100 were rare. The occasional melding Longevity in a wild bison popu- of smaller herd units into a much lation is usually less than that of larger group usually resulted from animals in zoos and other protect- disturbance by people or aircraft. ed circumstances. Longevity may Typically, even when 100 or more also vary among wild populations. animals were in sight at once in In Yellowstone, relatively few Hayden Valley during the sum- members of the population attain mer, they were in two or more old age, which probably begins at subunits which were often close 12-15 years of age (Fuller 1959). together, but did not actually form An occasional one of these aged one large herd. However, during bison is probably more than 20 the rut, the subunits sometimes years old (from Yellowstone trap melded although they were not records of 1964-65 and 1965-66). disturbed. Although mature bulls were commonly seen in the mixed Behavior Characteristics groups at all seasons, many bulls were separate from these groups. Grouping characteristics Some bulls (not always old ani- Bison are gregarious animals mals) were solitary, but pairs and usually found in groups of various small groups up to four and five sizes, although there are scattered were common, particularly in win- solitary bulls at all season. The vast ter. Occasionally a cow was seen herds (of plains bison) commonly with a bull group. Such cows were mentioned by historians are not without calves at the time, but seen in Yellowstone. Small bands, were not always old or barren as typical of the original mountain McHugh observed. Younger cows bison population (as described by were seen in bull groups several early travelers), are also character- times; one (a crippled cow) was istic at present. During the higher seen with a calf after wintering population levels of the 1950s, with a bull group. McHugh (1958) found that cow Small bands appear to be the (mixed) group size ranged from basic population unit, but the na-

10 to 50 in Lamar during the win- ture of these bands is not clear. ter, with a mean of 20. During the Fuller (1960) considered the ob- rut in Hayden Valley, he observed servations of various writers and a range of 19-480, with a mean of concluded that there was a basic 175. unit of some sort, centering At population levels of the pre- around 11-20 individuals. Mc- sent study, small winter groups Hugh (1958) concluded that were also characteristic; during subgroup and group formation General Characteristics 47

was flexible, with little dependence along with horning of trees and on blood relationship (except the ground, and more wallowing than

cow with calf). is observed at other times. Bulls do not dominate groups of cows as a elk (Cervus can- Behavior in harem unit, as do adensis), but are usually part of a specific circumstances mixed herd group along with other bulls of various ages. There was Historical references often men- no evidence from this study that tion that bison face into the wind solitary bulls were forced away during snowstorms. This may from mixed groups. have been very common among Bison are very agile, being able plains bison when no shelter was and willing to traverse fallen trees available. Conditions which prevail and steep slopes with speed. They during severe snowstorms in Yel- are capable of a top speed of 30-35 lowstone permitted few observa- mph (Fuller I960) and are strong tions during this study, but bison, swimmers. Although large, they

when visible at all, were not seen readily disappear in the forest, standing head into the wind. Rath- blending with the darkness of er, they were bedded in the snow, lodgepole pines. usually in whatever protection small variations in terrain offered. At times they were seen moving Senses and disposition with the wind, sometimes into the trees at the edges of the wintering Bison use the senses of smell, valleys. Dave Pierson (1971 pers. hearing, and sight. The sense of comm.) states that during the smell is well developed, and bison Buffalo Ranch operation in Lamar reaction to the odor of an observer he often saw bison on the open is often more marked than reac- feedgrounds facing into the most tion to sight or sound. Bison are severe winter storms. typically alert and are wary of an During the breeding season observer whether seen or heard, (rut), bulls engaged in consider- but a careful approach to a view- able head shoving, but actual bat- point is often possible if the wind tles were never witnessed. Fuller has not carried the scent to them.

(1960) witnessed shoving matches After an observer is scented, flight between bulls, but most encoun- is usually immediate for at least a ters were decided by threats. short distance. McHugh (1958) described battles Sight more frequently causes but did not state that these were flight than does sound, and an between unfenced bison bulls. The observer sighted on foot is more bulls do a great deal of bellowing, disturbing than one on horseback. .

48 Bison of Yellowstone National Park

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In winter a skier is usually detect- indifference" for the bull groups. ed as soon as in view of a herd, al- All bison should be viewed from a though the skier may be a mile or respectful distance. more away. However, if the skier uses white clothing, approach to Visitor less than 100 yards is sometimes possible unless scent disturbs the opportunities to see bison bison. One exception to the usual wari- Bison behavior and habits (see ness of bison is common. Solitary Movements) influence opportuni- bulls are probably as aware of an ty to see them from park roads observer in a given set of circum- (Table 8). Such viewing is best stances as is a group of bison. done from a vehicle, to minimize However, these bulls are much disturbing the animals and de- more inclined to stand their stroying the opportunity for oth- ground, particularly near roads, ers to watch. where they are more accustomed The visitor who is able and will- to people. Their tolerance of ap- ing to penetrate the wilderness of proach is misleading; they are not Yellowstone on foot or horseback aggressive, but when approach is may, with luck, see the herd beyond tolerance, they will depart. groups on their summer ranges. The line of departure may be The herd groups in Yellowstone through or over unwary people can be characterized as very elu- who sometimes nearly surround sive and very mobile, and a sight of one of these bulls. them is not always possible even Observations made during this for the experienced observer. But study concur with those of Fuller the opportunity to watch a group (1960), who reported that bison of truly wild bison, living as they were neither aggressive nor un- have for generations in this high predictable. He characterized the mountain wilderness, is an experi- mixed herds as usually shy and ence to be remembered and cher- timid and used the term "stolid ished.

521-650 O - 73 - 5 5 Population Characteristics

This chapter discusses the mar; the 1964-66 study sampled REPRODUCTION and population the entire free-ranging popula- structure and dynamics of Yellow- tion. The rates of pregnancy in the stone bison during the period younger age classes are suggestive 1964-68. A series of bison reduc- only, due to limited sampling. The tions from 1961 through 1965 1940-41 study of the semidomestic consistently removed a large num- herd indicated that an occasional ber of breeding-age females. Re- female bred as a yearling. None cords indicate that the reductions (of 15 sampled) was found to be by field shooting of the mid-1950s pregnant in the later study of wild also did this, as did some of the bison. The 1964-66 study indicat- earlier removals at the Buffalo ed that a few more bred as 2-year- Ranch in Lamar (Table 9). Some olds and that approximately a population characteristics may fourth of the 3-year-olds were change after a period without breeding. Both studies showed

reductions . Data for all categories that the majority of females at- were not obtainable each year; tained sexual maturity when 4 hence, selected figures are used in years old. some instances to suggest popula- Sexual maturity for the female tion conditions. population as a whole may be occurring somewhat later now. The 1964-66 study of wild bison Sexual Maturity showed fewer females pregnant in the 3.5 and 4.5 age classes (27 and Incidence of pregnancy by age 71%, respectively) compared with class for two Yellowstone studies 1940-41 study of the semidomesti- 25 years apart are compared in cated bison (50 and 92%, respec- Table 10 as an indication of sexual tively). maturity in the female population. Sexual maturation also may be The 1940-41 study sampled the later in the Yellowstone popula- semiranched population of La- tion of this study compared with

50 Population Characteristics 51 herds elsewhere. At Wood Buffalo all age classes over 2.5 years com- National Park, 36% (160 sampled) pared with the semidomesticated of the Hay Camp and 59% (17 herd of 1940-41 (Table 10). Fe- sampled) of the Lake Claire 2- males 3.5 years of age and older year-olds were pregnant. Rates averaged 56 and 90%, respective- were 52% at both locations (92 and ly. Females 4.5 years and older 31 sampled, respectively) for 3- averaged 62 and 90%, respectively. year-olds (Fuller 1962). At Wichi- Table 1 1 compares reproductive ta, 74% (35 sampled) of the 3-year- data recorded at Lamar by Rush old cows had calves (Halloran (1932a), several later unpublished 1968). compilations also made at Lamar, Sexual maturity of males was and this study of the entire popu- not studied in Yellowstone. How- lation. The pregnancy rate of 52% ever, Fuller (1962) found that for females 2.5 years of age and examination for spermatogenesis older determined in this study was showed the age for males to be the lowest recorded in Yellow- comparable to that for females: a stone. The reason for this was not few mature as yearlings, a third as clear, because the age classes rep-

2-year-olds, and probably all oth- resented in all previous compila- ers by 3 years of age. Halloran tions (except 1940-41) were not (1968) found that two experimen- recorded. The rate of 65% in tal bulls were effective sires as 2- 1931-32, which was lower than year-olds. According to observa- others prior to this study, may tions made by McHugh (1958) in reflect a high percentage of aged Hayden Valley in Yellowstone, females in that sample, as few cows males 8 years and older were the were removed from the semi- most active sexually, as indicated domestic herd before 1930. The by "tending bonds"—the term he influence of ranching practices used for the relationship between such as winter feeding and culling a bull and a particular cow during of aged animals for many years the rut. Fuller (1960) also ob- may account for subsequent high served that only fully mature pregnancy rates. males tended cows. Apparently, Yellowstone's present wild bison sexual maturity in males occurs population showed a reproductive well before they are a part of the rate equal to the 52% reported by active breeding population. Halloran (1-968), and lower than

the rate among all populations compared by Fuller (1962). Hal- Reproduction Rate loran attributed the low rate at Wichita Mountains Wildlife Re- The present wild population fuge to high calf survival. Calves showed a lower pregnancy rate in were known to nurse into their Bison of Yellowstone National Park Population Characteristics

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TABLE 10. Comparison of female pregnancy rates, by age classes, 1940-41 and 1964-66.

No. sampled Percent pregnant

a a Age class 1 940-4 l 1964-66 1 940-4 l 1964-66

2.5 2 7 14

3.5 4 11 50 27

4.5 13 7 92 71

Young adult 10 6 100 50

Adult 49 23 86 57

Aged 8 17 100 75

Entire sample 86 71 86 52

a From Skinner, Curtis K. 1941. Special report on Yellowstone National Park bison. Yell. Nad. Park Bio. Files, 715-03. Buffalo (General). Typed.

second year of life, thus prolong- in the low incidence of pregnancy. ing the physical drain on the cows Rate of infection according to tests (and perhaps influencing the pos- from 1964-66 averaged about 54% sibility of conception). Fuller con- for Lamar, 42% for Pelican, and sidered brucellosis infection and 26% at Nez Perce Creek in the Fi- severe climate as possible adverse rehole area (Barmore 1968). influences on reproductive rates in These rates were all lower than the Wood Buffalo National Park. 62% at Lamar in 1941 when the Calf survival apparently was not pregnancy rate, at 86%, was much an important influence on the re- higher than now. Although Rush productive rate determined by the (1932a) mentions that a number present study. Although survival of abortions were known to have appeared high (see Calf Mortali- occurred, abortions were appar- ty), no yearlings were observed ently rare except in the crowded nursing during the study- Only 4% corral at the Buffalo Ranch (Dave of the cows (Table 11) examined Pierson 1968 pers. comm.). Quor- during the mid-winter reductions trup (1945) stated that brucellosis were still lactating. had little or no effect on the herds, Brucellosis in Yellowstone ani- as did Tunnicliff and Marsh (1935) mals did not appear to be a factor and McKenney (Skinner 1941). 1 1

Population Characteristics 55

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Differences in population age among subadults. Houston (1968) structure, as reflected in the sam- suggested that animal nutrition ples, partly explain differences in during winter periods might con- reproductive rates between the trol yearling moose (Alces alces) wild bison popultions of Wood ovulation rates. Robinette et al. Buffalo and Yellowstone National (1955) attributed reproductive parks. Subadults and young adults rates among yearling mule deer formed a much larger part of the (Odocoileus hemionus) to the type Wood Buffalo National Park sam- of winter preceding that during ples (Fuller 1962); aged animals which the pregnancy rates were formed more of the Yellowstone determined. Possible variation in sample. However, all age classes effects between mild and severe (except the aged) in Yellowstone Yellowstone winters was not ob- showed a lower reproductive rate. tained during this study. The low reproductive rate in The influence of Yellowstone Yellowstone may result from a winters on reproductive rates complex of environmental factors, among adult bison was unknown. in part related to severity of the Pregnancy rates among adult winters. Both Yellowstone and moose in Jackson Hole, south of Wood Buffalo National parks have Yellowstone, approximated those severe winter conditions, but the from other ranges (Houston details differ (Table 12). Fuller 1968). Other environmental fac- (1962) believed extreme cold, per tors which were not apparent from se, had little effect on bison, but this comparison of Yellowstone was important when there was and Wood Buffalo National parks wind. Wood Buffalo National may be important in affecting Park, compared with Yellowstone, adult reproductive rates. is colder, but has less snow and fewer periods of crusting condi- Fetal Sex Ratio tions during the winter. Trees provide protection from the wind. The fetal sex ratio was not esti- Differences in amount of wind mated during this study. However, were not as apparent. Yellowstone records kept by Rush (1932a) and apparently has a more severe win- during four later reductions in ter environment, for bison, than Lamar (Table 11) showed more does Wood Buffalo National Park. males among fetuses, ranging The effects of the Yellowstone from 108 to 163 males/ 100 fe- winters on subadults is suggested males and averaging 127 males/ 100 by the mortality among them, as females (294 fetuses). This was

discussed later. Winter conditions, slightly higher than the 1 12 males/ perhaps through nutritional influ- 100 females reported by Fuller ences, may delay sexual maturity (1962). Population Characteristics 57

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Number of Young at Birth captures older than 3.5 years were males, compared with 37% in No twin fetuses were noted in 1964-65 (Nez Perce trap). In addition of any of the above records. One in- to the influence snow depth stance of twins in the Lamar herd on trap success, animals trapped was reported (McHugh 1958). the previous year seemed harder Other workers (Fuller 1962; Hal- to herd. loran 1968) and historical accounts Age classes for all females agree that twins are rare. trapped (Table 13) provided population sex-ratio information for animals less than 4.5 years of age. Population Structure The records for all traps suggest that a slightly higher percentage of Sex and age structure was sug- female calves survive their first gested mainly by trap records year than do males, but the pooled made during live-trapping opera- data for yearlings and 2.5-year- tions from late December to late olds suggest no further differential February in the winter of 1964-65, loss for this period. The variabili- and from mid-January to mid- ty, when individual trap records March 1966. Efforts were made to are compared, among the percen- trap as many of the Lamar (Crystal tages of females in the 2.5- and trap) and Mary Mountain (Nez 3.5-year-old classes may reflect the Perce trap) animals as possible. removal of calves in reductions of More were trapped during the 1961-62 (Lamar) and 1962-63 severe winter of 1964-65 than in (Mary Mountain). Although this 1966. Trapping success for calves may explain the very low percent of the previous spring was nearly of 3.5-year-old females taken at 100%, as indicated by comparison the Lamar trap, all trap records of 1964-65 Mary Mountain early suggest that fewer females survive winter aerial count records (72 in this age group. Thus, female calves) and Nez Perce trap records survival may be favored the first (77 calves). Most yearlings were year, but male survival may be probably trapped. Success (indi- favored the next 3 years of life. cated by the temporary backtags Fuller (1960) also noted more and the number of retrapped males than females in the spike- animals) was high in the 2.5- and horn, or 2.5- to 3.5-year-old 3.5-year-old classes, but a few group, but believed the identifica- undoubtedly were not taken. Most tions were biased. By 4.5 years of adult females were trapped; trap age and older, differential survival success was lowest for males of age cannot be distinguished from dif- classes above 3.5 years, particular- ferential trap success.

ly in 1966. That year only 7% of all Trap records, together with the Population Characteristics

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Buffalo National Park. Adult male Mountain were 7, 14, and 7%, re- bison may be "biologically expend- spectively, during the spring of able" according to Etkin (1964), 1965 after reductions in all three who states that sexual dimorphism areas removed large numbers of

(termed aggressive potential in cows. Thereafter, all percentages bison) interferes with male surviv- increased. By 1968 the Pelican al. population, where the fewest cows Age classes were calculated for were removed showed what may be the Mary Mountain population, a nearly "normal" (uninfluenced using the Nez Perce trap records by reductions/ 18% calves. The of 1964-65 and the prereduction higher percentages in Lamar Population Characteristics

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(27%) and Mary Mountain (25%) uninfluenced by recent reductions. for 1968 probably reflect the higher pregnancy rate of an increased proportion of younger females. Mortality Although the number of animals Calf mortality sampled was not large, the 1968 samples represented 95, 75, and The expected number of calves 40% of the Pelican, Lamar, and from the 28 females of breeding Mary Mountain mixed herd age released from the traps during groups. the reduction of 1964-65, using Pooled percentages for the the observed pregnancy rate of three herds in 1967 (20%) and 52%, was 15. The actual number 1968 (19%) suggest a leveling in seen in those groups in the spring calf production for the population of 1965 was eight. The difference as a whole. If so, then the usual probably represented loss of em- proportion of newly born calves in bryos or neonates. A realistic per- mixed herds of Yellowstone bison centage of such loss for the entire may be 18-20%. Additional data, population could not be judged free from possible reduction influ- from the limited information. ences, are needed to verify this. Field observations of the rela- Spring calves as a percentage of tively small bison population of the the total population (mixed herd study period suggested that little groups, bull groups, and scattered additional calf mortality took animals) were calculated only in place before late the following 1967 from a very accurate (397 winter (March and early April). count, 400 estimate) census of the Throughout 1966 and 1967, dur- entire park just before calving sea- ing and after calving season in son. Calves formed only 11% of Lamar and Pelican, periodic the 1967 spring total population, ground and aerial checks were compared with 20% of the mixed made. The agreement on total herd groups. Although, as pre- number of calves seen was quite viously discussed, 20% calves in consistent. Size and color of calves mixed herd groups may be nearly helped to confirm that loss, bal- normal, 11% calves among the anced by addition of some late total population may be low. Re- calves, was not occurring. Calf ductions have removed a larger percentages of herd numbers proportion of mixed herd animals throughout the year (Table 15) than of bull groups and scattered were inconclusive, showing in- animals. As a result, the total of creases in 1965 and 1966, and mixed herd groups may form a slight decreases in 1964, 1967, and smaller part of the 1967 popula- 1968. Size of some of the samples, tion than it would of a population skill of the observers, and variable Population Characteristics

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1-1 CO

o C7> 64 Bison of Yellowstone National Park

conditions of weather and animal 1962-63 at Nez Perce) may have visibility may have affected the affected the size of some age class- quality of the counts. The percent- es, but do not explain the similar ages did suggest that there was no pattern of percentages among appreciable calf loss. Trap records subadult age classes recorded at for 1964-65 from Nez Perce both traps in 1964-65. showed a ratio of 61 calves per 100 cows (2.5 years of age and older) in The calculated age classes of the winter, although among cows 1964-65 Mary Mountain winter removed from the same popula- population (16% calves, 11% year- tion that winter the pregnancy rate lings, 6% 2.5-year-olds, 67% older) was 51%. The sampling may have suggested that half the calves been biased, the previous year's which survive into their first win- pregnancy rate may have been ter die before 2.5 years of age. Calf higher (unlikely because of a large numbers indicated a potential 16% reduction in 1962-63), or mortality increase. Realized percentages for may have occurred in older age yearlings and 2.5-year-olds were classes, but calf mortality was not 13% (11/84) and 8% (6/73), re- indicated. In contrast, Fuller spectively. These indicate a 19% (1962) found a steady decline in loss between the first and second calf percentages from a peak of winters, and a 31% loss between 23% of herd numbers in July to the second and third winters. This less than 10% by the end of the mortality most likely occurs in late calendar year. winter (March and early April) at the end of the first and second years of life, rather than early in Subadult mortality winter during the second and third years of life (see Other Mor- Trap records (Table 13) suggest- tality). ed considerable mortality among subadults. The records show that a Variation in subadult mortality progressive decline in numbers rates probably occurs, but cannot occurred between calf and year- be judged from the limited data. ling, and between yearling and Previous reductions, as discussed 2.5-year-old age classes. One ex- above, probably had less influence ception, an increase in percentage on subadult mortality than did of yearlings compared- with calves environmental factors. Because at the Nez Perce trap in 1965-66, this population had not been sub- may have been caused by a shift of ject to an unusually severe winter a mixed herd group from one win- for several years, these percen- ter range to another. Previous tages may approximate usual mor- reductions (1961-62 in Lamar; tality among these age groups. Population Characteristics 65

Other mortality programs, but the number of dead animals found indicated greatly Natural mortality recorded dur- increased mortality. ing the study period totaled 49 animals. All but one occurred during the winter after considerable Population Trends snow had accumulated, usually after January. The number of re- Figure 24 shows population corded deaths were 38, 4, 3, and 3 trends based on actual counts (post- for the winters of 1964-65 (a se- reduction, precalving) from 1936 vere winter), 1965-66, 1966-67, through 1968 for the entire park, and 1967-68, respectively. With as well as for the wintering subun- the exception of a small mixed its of Lamar, Pelican, and Mary herd group (18 animals), all dead Mountain. Known losses, mainly animals were found scattered on reductions, are also shown. The the winter ranges. Of the other 30 reductions, held only in Lamar recorded deaths, there were 22 prior to 1954, accounted for the aged bulls, 2 cows, 3 yearlings, 1 general downward trend in that calf, and 2 unknown. More bulls area, although at the same time may have been found because of the population as a whole in- larger carcass size. Reductions, by creased, influenced mainly by the removal of mixed herd animals, steady increase of the Mary Moun- may have substituted for propor- tain herd as it repopulated an area tionately more natural mortality uninhabited by bison for more among cows and younger animals than 40 years. The peak popula- than among bulls. tion in the latter herd and for the Natural mortality recorded total bison population in 1954 annually over mild and average apparently coincided with in- winters of the study period aver- creased use of the Madison Pla- aged less than 1% of the winter teau-Pitchstone Plateau summer herd numbers. One or two ani- range, as mixed herd groups were mals, usually bulls, were the most small and infrequently reported found dead in any one of the main from this area for nearly 15 years wintering valleys. This was also the after the 1936 reintroduction on usual number found before the the Firehole. During the early study period, according to earlier 1950s, ranger reports indicate ranger reports, although popula- yearly use by mixed herds, some- tion numbers varied considerably times large in size. In June 1952, (Appendix IV). The amount of 124 adults and 11 calves were natural mortality associated with a seen. severe winter such as 1964-65 was Since the 1954 peak, all popula- obscured by concurrent reduction tion segments have decreased.

521-650 O - 73 - 6 66 Bison of Yellowstone National Park

/9JS /940 /94S /950 /955 /960 /965 /970 Cumulative Populahcw a/umbexs

& so*

% zo°

pi re i'l I !. /9JS /940 /945 /9SO /9SS /960 /965 /970

fcwcr/cws

Fig. 24. Bison population trends from population counts, 1936-68.

The 1955 reduction in the Mary heavy in January, and severe cold Mountain area may have started was prolonged in February. A the downward trend shown be- large winter loss that year was indi- tween the counts of 1954 and cated by sightings of 20-30 dead 1956. The marked decrease in animals in Pelican during an aerial population numbers in the Mary census of late January 1956 (Jim Mountain and Pelican herds, and Stradley 1968 pers. comm.). The the smaller decrease in Lamar following June, 32 dead animals cannot be entirely due to the re- were counted in the main valley ductions of 1956; there was none (Larry Brown 1969 pers. comm.). in Pelican. The decrease coincided Reduction only added impetus, with the severe winter of 1955-56, apparently, to a natural occur- when snows were exceptionally rence. Population Characteristics 67

Immediate increase in the La- 1965. From the early 1920s mar numbers followed reductions through 1941, it fluctuated be- when population levels remained tween counts of 100 and 200; for well over 200 animals, before the next 10 years fluctuations were 1952, by which time the last ves- generally between 200 and 300 tiges of the Buffalo Ranch opera- animals. After the peak count of tion (feeding of hay) ceased. Since 461 in 1954, followed by the drop then, Lamar has shown only very to fewer than 100 in 1957, the slow increase, although reductions population again remained be- have been few and comparatively tween 100 and 200 animals. The small. Reported natural mortality lack of increase over fairly long (an occasional animal) indicated periods of time suggests some bal- that no more bison than usual died ance exists with environmental most years. Slight increases which factors, in which factors favoring showed in counts of 1956 and increase are usually offset by mor- 1961 were followed by reductions tality factors such as winterkill. each time. At least 50% of the The 1954 peak may have occurred 1962 reduction consisted of fe- with exceptionally favorable influ- males (yearlings and older). After ences, which existed only briefly. the 1965 reduction, only nine The park-wide population counts females (yearlings and older) and do not suggest that periodic emi- 10 female calves were released. gration from Pelican to Lamar or The temporary effect of even Hayden Valley could account for small reductions on low popula- the long-term stability, although tion levels was apparent, but some apparently temporary population increase (with recruitment of more shifts have occurred (see Mixing of breeding females into the popula- Population Segments). No herd tion) expected by 1968 did not groups were reported in Hayden occur. This suggests that some fac- Valley after 1895 until animals tor, other than reductions, may from Lamar were trucked there in have retarded increase in this 1936. Ranger reports made prior population at levels below 200 to the study period indicate that animals. The factor may be related reproduction by herd groups in to the change to a truly wild popu- Lamar and Hayden Valley proba- lation, subject to natural environ- bly accounted for the usual popu- mental influences. lation increases in those areas. The Pelican population in- Population estimates for the en- creased from near extinction tire park of 400 and 440 animals about 1900 to an estimated more in 1967 and 1968, respectively, than 100 animals in the early showed a 10% increment for that 1920s. It was subject to reductions period. Reduction effects and in- only twice, in 1956 and again in sufficient population data preclud- 68 Bison of Yellowstone National Park ed calculation of annual increment habited area (Mary Mountain). over a longer period. Later increases were apparently Between 1965 and 1968, when offset by reductions (Lamar), or by the study ended, the bison popula- reductions in combination with tion for the park as a whole periodically severe environmental showed only slight increase. Three conditions (Pelican, Mary Moun- years had elapsed since a major tain). At lower population num- reduction, and 2 years since a bers, less severe environmental small reduction. The apparent conditions appear adequate to increase in the Mary Mountain have offset increases and to have herd (Fig. 24) between 1966 and resulted in periods of near stability

1967 resulted from use of a low or very slow increase in all popula- actual count in 1966 rather than tion segments. the more accurate estimate. In all Presumably, the original wild bison population segments, there bison population which inhabited is the suggestion of some factor or the Yellowstone area throughout combination of factors retarding the year lived in some balance with increase, aside from the influence the prevailing environmental con- of reductions. ditions of that time. Fluctuations Environmental conditions have in numbers undoubtedly occurred continued to exert major influence as favorable conditions alternated on the bison populations in con- with periodically severe winters. junction with the activities of man. The present environment of the Population trends (since the near bison ranges of the park appears extinction of the original wild little altered by man's influence population about 1902) apparent- (with the possible exception of ly reflect, initially, reestablishment Lamar Valley), although the num- of populations on historic ranges bers of some of the predatory and which had been uninhabited by grazing mammals have decreased. any bison for some years (Lamar, The bison population may be ex- Mary Mountain), or where the pected to increase in the future numbers were very low (Pelican). (since population numbers of the Increase was rapid under condi- study period are the lowest in tions of semidomestication (La- many years after the reductions of mar), and when favorable environ- the 1960s), but may then establish mental conditions combined with a state of equilibrium with natural availability of an extensive, unin- environmental conditions. 6 Mortality Factors

Parasites Internal parasites

Yellowstone bison appear internal parasites which have been comparatively free from internal recorded from other bison herds parasitism. During the present have not been found here. study, parasite investigation centered on the occurrence of lungworm (Dictyocaulus sp.), as report- External parasites ed by Meagher (1966). Rate of infection for 185 animals exam- External parasites were not col- ined was 11.4%. Aged animals, lected from animals during the with an incidence of 35%, showed study period. Burger (1967a, the highest rate of infection, con- 1967b, 1969 pers. comm.), who trary to the situation in cattle, studied biting insects in Yellow- calves in- where show both higher stone during 1966 and 1967, re- cidence and intensity of infections. ported that mosquitoes (Aedes Dictyocaulus sp. has been reported sp.), blackflies (or buffalo gnats), from a few animals in Wood Buf- particularly Simulium venustum, falo National Park (Fuller 1961), horse and deer flies (Tabanidae), from the National Bison Range snipe flies (Rhagionidae), and (Locker 1953), from Elk Island members of the Muscidae may all National Park (Conner and Cor- have had some association with nell 1958), and from a fenced herd bison. The last two families were in Kansas (Frick 1951). most important. No other internal parasites were The genus Symphoromyia of found in the brief examinations the Rhagionidae apparently influ- made of bison during the present enced bison distribution during study. Locker (1953) recorded the summer months (see Summer only tapeworms (Moniezia bene- Range Movements). These small deni) in Yellowstone bison, occur- gray flies cling tenaciously, inflict a ring randomly among all age painful bite, and locally may be groups, at an apparently low in- very abundant. During the sum- tensity of infection. A variety of mer, bison are nearly naked, as the

69 70 Bison of Yellowstone National Park newly growing hair is very short, she died. Both carcasses were resembling fine, black plush. They nearly consumed by scavengers are particularly vulnerable to bit- before examination was possible, ing insects. but the fat-depleted bone marrow Three genera of Muscidae were in both cases indicated very mal- associated with bison in Yellow- nourished animals. Neither tuber- stone. The stable fly (Stomoxys culosis nor anthrax, which have calcitrans) and the horn fly (Hae- been important causes of mortality matobia irritans) were observed in Wood Buffalo National Park feeding on bison with no noticea- (Fuller 1961; Choquette et al., ble effect. The face fly (Musca au- 1966), have ever been detected in tumnalis) was first collected by Yellowstone. Burger in 1967. He suggested that Brucellosis (Bang's disease, this exotic species, if it becomes undulant fever in humans), caused established in Yellowstone, could by the bacterium Brucella abortus, cause eye disorders in bison. He occurs in the present bison popu- noted evidence of severe conjunc- lation. Whether the organism was tivitis associated with the presence introduced or was endemic among of this fly among bison at the Na- North American bovids is not tional Bison Range. known; it was first tested for and reported in Yellowstone in 1917. The rate of infection has varied Diseases considerably among tests made in different years during reduction Disease-caused mortality was operations, and also among the not identified in the present wild wintering populations of a given bison population, although out- year. In 1964-65, 129 animals test- breaks of hemorrhagic septicemia ed in Lamar, 33 tested in Pelican, in 1912, 1919, and 1922 caused and 302 tested at the Nez Perce considerable mortality in the intro- Creek trap showed rates of 59, 42, duced herd in Lamar Valley. In and 28%, respectively (Barmore two instances during the study, 1968). young animals died from causes Evidence suggests that brucel- which were not apparent when losis has little effect on the Yellow- ample food was available. One was stone bison. Limited examination a yearling female, observed by of reactors slaughtered during the park personnel for some time, study period indicated normal unable to keep up with the herd pregnancies. Rate of pregnancy animals, moving very little, and was apparently not influenced, as becoming gradually weaker. The discussed previously. Veterinari- other was a young cow, seen for ans who investigated brucellosis in several days at Old Faithful before Yellowstone before the study peri- Mortality Factors 71 od agreed that there were no ap- bison may indicate that mutual parent effects on the population adaptation or equilibrium exists, (Tunnicliff and Marsh 1935; Skin- as between parasites and hosts that ner 1941; Quortrup 1945). Quor- have long lived together (Allee et trup mentioned that few abortions al. 1949). Physiological effects of were observed and gross lesions brucellosis, if any, may contribute were rarely seen at postmortem to maintenance of the bison popu- examinations. Dave Pierson, Buf- lation within levels which the habi- falo Herder and Animal Keeper tat can support. over a period of 30 years, believed Brucellosis is of economic con- that observed abortions occurred cern to cattlemen, and of health as a result of the handling of preg- importance to the general public. nant females in chutes, and their It is presumed that bison can confinement in pens during the transmit brucellosis to cattle, be- reductions held at the Buffalo cause the causative organism is Ranch (1968 pers. comm.). Quor- apparently the same in both spec- trup believed that brucellosis had ies of bovids. Transmission tests probably existed in the Yellow- have not been made to verify this, stone bison for a long time, and but on the basis of the assumption, that they had acquired a natural the National Park Service has co- immunity. operated with the Department of Investigations among bison have Agriculture in brucellosis control apparently concentrated on the among bison. In Yellowstone, incidence of brucellosis rather cooperation has consisted of vacci- than its effects. Most bison herds in nation of calves and removal of the United States are maintained reactors during reductions (held in a brucellosis-free condition as primarily to cut herd numbers). part of the U.S. Department of This cooperation resulted in re- Agriculture brucellosis control duction of animal numbers below program. In Wood Buffalo Na- the park's management objective tional Park in Canada, where the at Lamar in 1964-65. No reduc- presence of brucellosis was con- tions have been held specifically firmed in 1956, Fuller (1962) con- for brucellosis control in Yellow- sidered it a possible influence on stone. conception rate. Choquette et al. Participation in brucellosis con- (1966) also assumed that brucellos- trol in Yellowstone National Park is influenced productivity. Among has recently been reevaluated by cattle, effects include abortion of the National Park Service (Bar- calves, temporary sterility, and more 1968). Present bison man- lowered milk production (Gilman agement objectives are to maintain and McAuliff 1956). a wild population under natural Further studies of brucellosis in conditions. By order of the Super- 72 Bison of Yellowstone National Park

intendent of Yellowstone National observed with the cows. Park, future reductions will be Wolves (Canis lupus), which are held only when research clearly known to prey on bison in Wood indicates that compensation for a Buffalo National Park according to lack in natural controls is neces- Fuller (1961), are the only other sary. As an alternative to brucellos- likely predators of bison in Yellow- is control within the park, the stone. Studies such as that made by objectives of the Department of Mech (1966) have indicated that Agriculture control program can effective wolf predation on large be met by preventing contact be- mammals results from the cooper- tween park bison and domestic ative efforts of a pack. During the livestock beyond the park bounda- study period wolves were rare in ries (see Movements Beyond Park Yellowstone, with no pack activity. Boundaries). The observed survival, for a long time, of handicapped or weakened bison provided addi- Predation tional evidence that almost no predation was occurring. In one There was no direct evidence instance, a cow survived at least 2 for predation on the present herd. years with a useless right foreleg. Circumstances suggested a grizzly Although her mobility was im- kill of an apparently healthy, ma- paired, she was usually with other ture bull in mid-summer of 1967. bison, at times a mixed herd, more Remains of bone and hair indicat- often with one or more bulls. Only ed the bull died at the edge of a once was she seen unaccompanied, small group of trees in a meadow, except for her calf of that spring. south of Hayden Valley. The lack Solitary animals were also usually of broken bones, the relatively free from predation. Old bulls, young age of the animal, and the obviously weak, were often ob- site of death all suggested a grizzly served for several winter months (Ursus horribilis) might have in nearly the same location along killed the bull. McHugh (1958) the road in Lamar, until finally also mentioned indirect evidence they died. of grizzly predation. Dave Pierson Historical information suggests (1968 pers. comm.) believed both that even during the early years of black (Ursus americanus) and the park, when predators, particu- grizzly bears would take calves in larly wolves, were more numer- the spring, but calf counts during ous, healthy bison of all ages were the study do not indicate much relatively safe from attack. Al- loss. However, such loss might though predation becomes more have occurred at or immediately difficult as the prey species de- after birth, before the calves were creases (MacArthur and Connell Mortality Factors 73

1966), the predators in this case had alternate prey (elk) to sustain their numbers as bison decreased (from poaching). If bison had been easy or preferred prey, their increase, once they were protected from poaching, might have been prevented.

Other Causes

Winterkill, probably from the combined effects of climatic stress, forage availability, and physiologi-

cal condition of individual ani- Fig. 25. Trench left in soft snow by mals, was the main cause of ob- traveling bison. served mortality (see Other Mor- tality). Death usually occurred after prolonged weakening, often in late winter (March and early Observations during the mild April). A few animals died annual- and average winters of the study ly, but the number increased period indicated that snow depth greatly with severe winters. This did not limit forage availability. suggested that climatic influences Bison commonly cleared fairly (long winters, periods of pro- deep snow (by swinging the head longed cold, deep and sometimes in a sideways motion) with appar- crusted snow) acting directly and ent ease (Figs. 26, 27). McHugh indirectly on the bison were the (1958) observed bison feeding in most important mortality factors. snow up to 4 feet deep. At higher The most apparent direct effect population levels, snow depth may of the winter environment, above limit access to forage. However, the energy levels required to main- the size and location of the most tain body temperature, was the used foraging areas suggested that effort required to travel between this might happen only under the foraging areas. In deep snow the most extreme conditions (see Use mixed herd groups usually trav- of Forage Areas). eled in line, plunging to create Susceptibility to winterkill var- trenches several feet deep (Fig. ied according to physical condi- 25), frequently for more than a tion, as would be expected. Aged mile. Variations in topography animals found dead in mild and crossed added to their efforts. average winters indicated that they 74 Bison of Yellowstone National Park were most susceptible. Crippled and otherwise handicapped animals, and those weaker because of size, would also be affected more quickly. Differential and total mortality among subadults, as discussed previously, suggested that among otherwise healthy bison of all ages they were most vulnerable.

Size, together with social standing Fig. 27. Feeding site in snow approxi- in the population (see Suggested mately 2 feet deep. Mechanisms of Population Regu- lation), may explain this. A quick-acting type of winterkill occurred once during the study was too deep that winter to allow period, but old bison bones indi- the animals to move away from the cated similar occurrences in the slough area, and presumably they past. During the severe winter of starved to death when the small 1964-65, a group of 18 bison (in- amount of feed was gone. The cluding 3 calves, 2 mature and 1 slough area apparently becomes a spike bull, 7 cows of various ages, unique trap in severe winters, and 5 unidentified animals) died since 13 other bison survived in before the end of January at a Bechler that year, near the slough small warm-slough area in the Be- but along the river banks where chler Meadows. The snow there, movement was possible in the west of the Continental Divide, open water. Accidents accounted for the

deaths of a few individuals of all ages nearly every year, as indicated by ranger reports. Most commonly animals drowned in bog holes or fell into hot pools. The accidental death of whole groups while crossing thin river ice has been reported twice. At Slough Creek in 1941, seven yearlings and 2-year-olds died. In 1946, near the Mud Volcano, in the Yellowstone River, 39 died (including 5 calves, Fig. 26 Bull bison foraging in snow 9 yearlings, 6 two-year-olds, 2 approximately 2.5 feet deep. mature bulls, 16 mature cows, and

1 unidentified animal). 7 Habits

Calving

Comparison of records kept ed a size range from a 2-inch em- during the study period with ear- bryo to a 23-pound, 22-inch fetus; lier information suggested that the 80% of them weighed between 5 onset of the calving season is later and 20 pounds when examined in than formerly. From 1937 to late January (Appendix V). about 1950, the first calves were In all Yellowstone herds during regularly reported in Lamar be- the study period, most calves were fore mid-April. Since 1950, first born at about the same time (early calves have all been reported later. May). Observations of the earliest McHugh (1958) reported that calves were rarely possible except calving season extended from 15 in Lamar (because of limited ac-

April to 31 May, with more births cess before 1 May), but the few the first 2 weeks of May. During records made by rangers for the the study period most births oc- Firehole suggested that first calves curred during the first half of are usually born there perhaps a May, and calving season was over week later than in Lamar. by the end of May. There were Calves were born on the winter- always a few late births; occasional- ing areas (Fig. 28), except for the ly a new calf was seen in late sum- occasional late one. In Lamar dur- mer. (Subsequent to this study, ing this study, most calving took calving season has extended into place in the lower Lamar Valley June as the population has in- (west of Lamar Canyon in the area creased.) called the Horseshoe or Little Fetal size information compiled America). Ranger reports predat- before the study period also sug- ing the study indicated that this gested that a large part of the calv- same area was the usual place of ing extended over a longer period calving. In Pelican, most calving of time. Rush (1932a) reported occurred in the eastern half of the only that there was considerable main valley from Astringent Creek variation. E. R. Quortrup's unpub- to Raven Creek. Mary Mountain lished data (Skinner 1941) indicat- animals calved in both Hayden

75 76 Bison of Yellowstone National Park

Fig. 28. Calves (a few days old) born about 1, May 1970, when snow was on the ground later than usual. This cow was observed deliberately pushing these calves onto their feet—an action not seen other years. Photo by Mike Sample.

and Firehole valleys. On the Fire- of the rut in 1967, all of the ani- hole, most calves were born in the mals were at the crest of the Absa- Lower Geyser Basin areas of Senti- roka Mountains on the east nel Creek, Fairy Meadows, Pocket boundary, between the Hoodoos Basin, lower Nez Perce Creek, and and Canoe Lake. In other years the Firehole Loop. Most Hayden the groups were more scattered, Valley calving occurred in the some on the boundary and the western half of the big valley, near adjacent ridges between Cache Alum Creek. and Miller creeks, and some on Saddle Mountain. By the last week of July or the first week of August, Rut some of these animals crossed the Lamar River to the Mirror Pla- Most breeding activity occurred teau, where breeding activity oc- from mid-July to mid-August. curred from the meadows south of Field observations throughout the Amethyst Mountain south to the study indicated that every year, for meadows at the headwaters of Pel- at least a part of that time, most of ican-Timothy-Raven creeks. Most the herd groups which wintered in of the breeding activity in the Lamar and Pelican intermixed in Mary Mountain herd occurred in the Upper Lamar area. At the start the southwest corner of Hayden Habits 77

Valley and adjacent forest and Movements meadow areas. In all of these areas there were small uprooted coni- Migratory movements fers and many rubbed trees. Small Most of the bison in Yellowstone wallow-sized patches of grass (Fig. are migratory, moving in spring 29), apparently uprooted by horn- from the lower wintering valleys to ing but not much used for wallow- higher summer ranges, and re- ing, were another common sign of versing this altitudinal migration rutting activity. in the fall. The migratory pattern The period of breeding activity was most apparent in the mixed observed during this study (1963- herd groups which wintered in the 68) was shorter than that given by Lamar, Firehole, and Pelican val- McHugh (1958). He observed in leys. Although all groups of a par- the much larger Hayden Valley ticular wintering area did not population of that time that the move at once in spring, they all season extended from 15 June to moved within a few days' time. 30 September, with less activity Records kept during the study during the first and last 2 weeks. showed that mixed herd groups .

78 Bison of Yellowstone National Park wintering in Lamar moved 12-15 earlier spring than others of the miles to higher areas of Mount study, the mixed herd groups Norris and the Cache-Calfee moved from all three valleys by 24 Ridge during the first week of May. In 1967, the Pelican animals June, 3 of 5 years, and by the last were observed sequentially from week of May twice. Firehole ani- the air. They moved, in 2 days, the mals moved to Hayden Valley or 15 miles from the new spring the Little Firehole Meadows area growth of the upper Pelican Val- of the Madison Plateau during the ley, across high meadows, which first week of June, 3 of 4 springs. were mostly covered with snow or Wintering groups began to move standing water, to the Lamar Riv- from lower to upper Pelican Val- er. By the third day they were on ley at the same time. Some years, the greening slopes of Little Sad- further movement across the Mir- dle Mountain. They did not follow ror Plateau to the Upper Lamar any discernible vegetation or snow area was delayed until mid-June. melt sequence. Spring weather Observations suggested that near- patterns and temperatures pre- ly every year the entire Pelican sumably influenced the migration. population, except some bulls, Dave Pierson (1968 pers. comm.), crossed to the Upper Lamar, re- after years of observation, believed turning to the Mirror later in the that warm spring days were the summer. Most movements took main factor. place along definite travel routes, In the late fall the movement of as shown in Figs. 30 and 3 1 mixed herd groups was reversed, The bulls that wintered as soli- but occurred less abruptly than in tary animals, or in bull groups, left the spring. Lamar animals ap- the wintering areas gradually dur- peared in the main valley (to stay) ing the spring. The last of them by late November. Some groups disappeared several weeks after were reported in the Lower Gey- the mixed herd groups moved. A ser Basin about the middle of Sep- few bulls were usually seen from tember most years, although the the main roads in the Firehole, majority arrived in late October or Hayden Valley, at Mary Bay, and early November. Pelican animals in Lamar Valley almost to the end moved down sometime in the first of June. The bulls followed not 2 weeks of November, although only the routes used by the mixed groups commonly appeared ear- groups but moved upcountry lier for a few days at a time when along the various stream drainages fall snowstorms occurred. This to scatter widely on the summer intermittent shifting from summer ranges. to winter ranges during stormy The cause of the spring move- periods in the fall was also seen in ment was not clear. In 1966, an Lamar. Habits 79

Habits 81

Bulls commonly began to ap- Summer range movements pear on winter ranges before herd groups were reported. The move- During the summer, there were ment was gradual, continuing for extensive shifts of all mixed herd some time after herd groups groups on the various ranges. moved in for the winter. Most win- Animals which moved west onto ters, a few solitary bulls stayed at the Madison Plateau from the sites high on the summer range, Firehole, although few in number such as the heads of Opal and Flint during the study, commonly used creeks. the Buffalo and Little Firehole Cold temperatures alone did not meadows in early summer. From cause shifts from summer to win- there, they moved south along the ter ranges; immediately after a fall Continental Divide onto upper storm, in temperatures often near Boundary Creek and the western 0°F, herd groups which had end of the Pitchstone Plateau, moved down returned to high ele- remaining in these latter areas un-

vations. Snow depth and exposure til the fall move to winter ranges. to storm conditions at the higher Hayden Valley herd groups elevations apparently caused both commonly stayed within the main the final fall temporary and the valley much of the summer (Fig. movements to winter ranges. 32). Other years, by July, they

Fig. 32. Bison herd groups on Alum Creek in the western part of Hayden Valley. 82 Bison of Yellowstone National Park

Fig. 33. Bison on the strip of sedge meadows along upper Alum Creek south of Hay- den Valley.

ranged the small meadows and late July to early August, groups parks scattered in the extensive usually moved west down the lodgepole forest (Fig. 33) south to ridges, and some crossed the La- Dryad and Beach lakes, west to the mar River to the Mirror Plateau, upper reaches of Spruce Creek, where they ranged the northeast and across Mary Mountain to rim from Flint creek to upper upper Nez Perce Creek. Bulls Raven Creek until the shift to win- from Hayden Valley occasionally ter range. At higher population moved south down Arnica Creek numbers than those occurring to West Thumb and on toward during this study, groups also South Entrance. commonly moved the length of Pelican and Lamar wintering Specimen Ridge on the north edge herds were seen in early summer of the Mirror Plateau (Dave Pier- on the lower ridges of the Upper son 1968 pers. comm.). Lamar (Mount Norris, the western Apparent influences for move- ends of the Cache-Calfee and Mill- ment of groups over large areas er Creek ridges, and Little Saddle during summer were the rut, sea- Mountain). By the end of June to sonal vegetation changes (see Use mid-July, they moved higher, to of Forage Areas), and, most ob- the east boundary (Fig. 34), rang- viously, biting insect populations. ing from the Hoodoos to Canoe Small, gray, biting flies were par- Lake and Saddle Mountain. By ticularly noticed on the Mirror and Habits 83

Fig. 34. A herd group on the east boundary near Canoe Lake in early August. Photo by John Good, Yellowstone National Park.

the Upper Lamar in 1965. In feet, was much greater in 1967. He 1967, the flies were numerous in suggested that this influenced the those areas, and in Hayden Valley concentration of the entire Upper also. From mid-June to mid-Au- Lamar population of bison groups gust 1965, neither aerial flights high on the east boundary, at ele- nor ground checks showed mixed vations of 9500-10,000 feet, for herds on the Mirror Plateau, al- more than 2 weeks in late July and though in 1966 groups were seen early August 1967. Other sum- there by 24 July. From mid-June mers, although the same boundary to early August 1967, herd groups area was used by bison, they did were observed only once in Hay- not remain as long and were more den Valley, but were seen, from broadly distributed. the air, to the south. Every year Apparently, the insect popula- herd groups were seldom ob- tions influenced bison distribution served in Hayden Valley during and concentration more strongly much of July when biting insects than did breeding activity. In were at their worst. 1966, with fewer biting flies, Burger (1967a) compared biting mixed herd, groups split and insect populations and animal dis- moved from the Upper Lamar to tribution in 1966 and 1967. He the Mirror while the rut was at noted that the distribution and peak. In 1967, a similar move did abundance of species of Sympho- not occur until both the insect romyia, a small gray biting fly, par- populations and the rutting activi- ticularly at elevations below 8500 ty began to diminish.

521-650 O - 73 84 Bison of Yellowstone National Park

The spring and fall migratory locality for days or even weeks. habits of the Yellowstone bison did Bull groups occupied smaller not prevent animals from occa- areas for longer periods. Solitary sionally visiting areas of winter bulls sometimes spent the entire range during the summer. Ob- winter at one site. Presumably, the servations made during the study amount of movement was usually period and earlier ranger reports related to group food require- indicated that scattered bulls ments. Winter conditions hin- sometimes appeared on all winter dered but did not prevent occasion- ranges. When population levels al extensive movements by groups were higher, mixed herd groups and single bulls between main win- also occasionally visited winter tering valleys. Reasons for such ranges for brief periods, according moves were not apparent, but for- to ranger reports. Such groups age requirements did not appear were sometimes seen in the main to be a factor. No movements to Lamar Valley in mid-July, or more areas of high summer range dur- commonly, in August. Mid-sum- ing the winter are known; the soli- mer movements of groups rarely tary bulls wintering in these areas occurred to areas near roads in the arrived in fall. Firehole. No groups were report- Mixed herd groups moved most ed near the main road through frequently between Hayden Valley Hayden Valley in mid-summer, and the Firehole. In January 1965, nor in the main Pelican Valley. after attempts to drive animals No. reason for these mid-summer from Hayden Valley to the Nez movements was apparent. Perce Creek trap with helicopters failed because of the above-average snow depths, most of the herd animals crossed of their own voli- Winter range movements tion a few days later. The follow-

During the winter, all bison ing winter, during the 1965-66 (mixed herd groups, bull groups, reduction, neckbanded animals and solitary bulls) moved shorter released from the trap were seen a distances and less frequently than few days later in Hayden Valley. in the summer. Movement was Before the present study, in usually confined to the limits of March 1945, 54 bison traveled 6 the wintering valleys (see Numbers miles across Mary Mountain in 42 and Distribution), with egress inches of snow, according to difficult if not impossible after McHugh (1958). The frequency of considerable snow had fallen. such crossings, uninfluenced by Mixed herd groups moved most reduction operations, was un- frequently and for greater dis- known. tances, but sometimes stayed in one Mid-winter movements between Habits 85

Lamar and Pelican valleys appar- yond the north boundary. Since ently involved only bulls. Some- 1951, a few bulls have been report- time between early December ed almost every year beyond the 1965 and mid-January 1966, a southwest boundary in Idaho. marked young bull crossed from These movements have occurred Lamar, presumably by way of the regardless of fluctuations in popu- Mist Creek divide. Rangers report- lation numbers. ed movement on this same route Mixed herd groups have only by bulls in February 1932 and been reported beyond the north January 1949. Jim Stradley (1968 boundary of the park. Late during pers. comm.) saw a few mixed the winters of 1943 and 1948, herd groups crossing from Pelican groups briefly left the park near into Lamar in early winter about Gardiner, Montana. Severe weath- 1955-56. er conditions partly influenced Movements between Pelican and these moves. In summer 1943, Hayden valleys apparently oc- nearly 150 bison were seen just curred in the fall and early winter, outside the northeast corner. In but sightings were rare. The trails the fall of 1947, 31 were 8 miles of solitary bulls were followed north of the boundary on Elk from the air in January 1968. Creek in the Hellroaring area (R. Mixed herd groups were reported Murphy 1970 pers. comm.). All only once during the study period these mixed-group movements east of the Yellowstone River near occurred when larger numbers of the Mud Volcano, but earlier re- bison wintered in Lamar. ports indicated an occasional group in late fall. Jim Stradley (1968 pers. comm.) observed from Mixing of the air about two dozen cows and Population Segments calves moving between the two areas about 1956-57.

Census records, aerial observa- Movements tions, and the limited records of beyond park boundaries neckbanded bison (Fig. 36) indicated that movements of population groups affected numbers in- Since the early years of the park, habiting the winter ranges from few bison have moved beyond the one year to the next (population boundaries (Appendix VI). Figure shifts), and resulted in interbreed- 35 shows the locations of reported ing between populations of winter- movements, which usually in- ing areas during the summer. volved one or more bulls. Most Movement occurred during the years some bulls summered be- fall and winter between the valleys 86 Bison of Yellowstone National Park

Fig. 35. Map showing known locations of bison movements across the boundaries of Yellowstone National Park.

of the Firehole, Hayden, Pelican, son, justified considering them as and Lamar, as previously dis- one population, called the Mary cussed. Observations confirmed Mountain herd, distinct but not the assumption made by. park per- isolated from the other two herds. sonnel some years ago that the Shifts of other population extent and frequency of mixing groups were indicated by some between the Firehole and Hayden fluctuations in actual winter counts Valley animals during most of the from 1935 to 1950 (Fig. 37). De- year, including the breeding sea- creases in Lamar winter numbers Habits 87

Fig. 36. Neckbanded bison in a group at Pocket Basin on the Firehole. Photo by John Douglass, Yellowstone National Park.

coincided with increases in Pelican in 1937, 1941, and 1942; decreases in Pelican winter numbers coincided with increases in Lamar in 1940, 1943, and 1949. Reductions, made only in Lamar during this period, probably added to the amount of decrease there in 1941 and 1942, but could not have influenced the 1937 decrease nor any Pelican decreases. Bias in Peli- can population counts made by rangers on winter ski trips might /935 /940 /945 /9S0 account for some variation, but not the coincidence of changes in population numbers in the two valleys. Mixed herd groups which moved between Lamar and Peli-

II I I 1 I can in late fall and early winter probably remained on the winter range that was in use when weath-

Fig. 37. Population fluctuations in win- er conditions worsened. tering areas caused by shifts of Shifts between Pelican and mixed herd groups. Hayden Valley were infrequent 88 Bison of Yellowstone National Park and less obvious. Such shifts did neckbanded in Lamar showed occur in 1941 and 1946 (Fig. 37). that, during the breeding season, Other shifts have occurred since, intermingling of the Lamar and but the less frequent population Pelican wintering groups was ex- counts made after 1950 gave no tensive most years. In 1967, all of indication. During the study peri- them mixed together in several od, aerial observations and reduc- large, flexible groups at the crest tion records suggested two shifts of the Absarokas for more than 2 occurred. Mary Mountain popula- weeks. The amount of interbreed- tion counts after the 1964-65 re- ing which presumably would occur duction totaled fewer than the in such circumstances suggested expected number of animals, that these bison also be considered based on numbers seen before one population segment. Howev- trapping began (480), numbers er, because winter season move- removed (238), and possible natu- ments were so few, the separate ral mortality. A move of animals to designations were retained. Pelican after the early December Separation was most complete count would explain the discrep- between the Mary Mountain pop- ancy. The next winter, in the re- ulation and the Pelican-Lamar duction of 1965-66, 47% of the animals. The infrequent move- animals (yearlings and older) ments between Pelican and Hay- trapped at Nez Perce had no metal den Valley at any time, coupled eartags, showing they had not with the separation of the popula- been trapped the previous year. A tion segments during breeding movement into Hayden Valley season, resulted in almost no inter- from Pelican was the probable mixing. explanation. Historically, when there were Apparently, the shifts indicated large summering populations in Fig. 37 were temporary, usually (parts of which wintered beyond for the one winter. The presence the park area) north of the Lamar of a mixed herd group (34 ani- and west of the Firehole, inter- mals) wintering in Bechler Mead- breeding between the wintering ows in 1962-63 also indicated this. populations of the Lamar and Peli- No herd group was reported there can valleys, and of the Firehole in 1961-62 or 1963-64. Over a and Hayden valleys, was probably span of time, the wintering num- less extensive because of geo- bers of the Mary Mountain, Peli- graphic separation of some groups can, and Lamar population seg- during the summer. Then as now, ments would be unaffected by such however, the groups which shared shifts. summer ranges undoubtedly in- Observations of both total num- terbred. Before intensive poach- bers of animals and individuals ing greatly reduced numbers and Habits 89 probably altered or eliminated when trapping operations again habitual patterns of movement, began during the winter of 1965- there may have been more contact 66 were driven across to the Fire- between Pelican and Hayden Val- hole side to the trap on Nez Perce ley animals, but the amount of in- Creek. Aerial observations after termingling and interbreeding was the trapping showed that several probably least, even then, of the bison, neckbanded and released, population segments. recrossed the divide to Hayden Geographic separation during Valley immediately. During the the breeding period through sea- winter of 1966-67, when there was sonal migration to higher summer no trapping, five marked animals ranges, seen in the present park (neckbanded in 1965-66) wintered bison on a local scale, could ex- in Hayden Valley: an adult cow, a plain the existence of two recog- 4-year-old cow, a 2-year-old cow, nized subspecies of bison in histor- and two young bulls. Three ic times whose distribution pre- marked adult cows wintered on sumably overlapped in the Rocky the Firehole in both 1966-67 and Mountains (Skinner and Kaisen 1967-68 although they were iden- 1947). Possibly the mountain and tified in Hayden Valley during plains types jointly used some win- summers. Less complete records tering places along the east side of on other marked cows also suggest the Rockies, but breeding isolation affinity for a particular winter kept the populations distinct. range although most mixed herd The apparent temporary nature groups summered in Hayden of group population shifts be- Valley. tween main areas of winter range, discussed previously, and neck- Records for the animals marked band records both suggest that in Lamar further suggest that the animals have affinities for particu- tendency to winter habitually in lar winter ranges. Neckband rec- the same valleys was stronger ords for the Mary Mountain herd among mature females. Marked showed that some individuals pre- animals of all ages were seen on ferred one winter valley to the various parts of the summer other, regardless of movement range, including Raven Creek on between the two valleys at all sea- the Mirror Plateau (close to Peli- sons. The entire population (ex- can Valley), but only three imma- cept for the many scattered bulls) ture bulls and two immature fe- had crossed to the Firehole side males spent at least one winter in during the winter of 1964-65 Pelican Valley. Cows marked as when helicopters drove them to- adults (five marked) were identi- ward the trap on Nez Perce Creek. fied in winter only in the Lamar Most summered (1965) in Hayden Valley, two of them for three suc- Valley. Those in Hayden Valley cessive winters. 90 Bison of Yellowstone National Park

A tendency for animals, particu- entirely within the park bounda- larly mature females, to prefer a ries throughout the year. Those given winter range might explain that range to the northeast (Lamar the lack of any lasting interchange and Pelican) are almost separate or permanent shifts by groups from those designated the Mary from one winter range to another. Mountain herd. Affinities for giv- The lack of emigration to new ter- en winter ranges are responsible ritory, such as from Pelican to for much of the separation, which

Hayden Valley before the rein- is reinforced by migratory habits troduction of 1936, might also be which maintain a breeding season explained. Possibly, except for isolation. Occasional movements young animals or old bulls, inter- by bulls and mixed herd groups change between wintering valleys prevent total separation of any one involved only groups. Although part of the population. the basis of such groups is not known, observers generally agree Food Habits that a group structure exists. Ful- ler (1960) believed there was a unit Results of analysis of 22 rumen of some sort. McHugh (1958) be- samples, half of them collected in lieved the groups were flexible and the winter and half throughout depended little on blood relation. the rest of the year, are shown in He did observe that cow (mixed Table 17. The 1 -quart sample tak- herd) groups were usually led by en represented approximately 1% mature females. These cows would of the rumen-reticulum volume of then govern the movements made 91 quarts averaged from eight by the groups. adult males. Approximately two- Bison have shown willingness to thirds of the samples were taken move considerable distances in from adult males. Because of some rough topography or deep snow, uncertainties in distinguishing according to the time of year, but between sedges and some grasses, they do not all intermix freely. doubtful material was placed in Their movements follow repetitive the grass category. Sedge may thus patterns which indicate habit as be underrepresented in the analy- well as physical need. The move- sis. ments of both individuals and Grasses and grasslike plants groups result in a varying amount formed most of the diet through- of separation among population out the year. Totals were 99, 96, segments which winter in the val- 91, and 99% for winter, spring, leys of the Firehole, Hayden, Peli- summer, and fall, respectively. can, and Lamar (Table 16). The Sedge was the main source of for- Yellowstone bison of the present age at all seasons, averaging more

(and recent past) remain almost than half the diet. Its value in win- Habits 91

TABLE 16. Comparative summary of movements shown by the present wintering populations.

Firehole-Hayden Pelican-Lamar Valley Populations Populations

Winter separation Partial Almost complete Almost complete

Group movement Frequent — year Least frequent — Infrequent — fall between valleys around fall and early and early winter wintera

Seasonal migrations Less marked Quite marked

Summer interbreeding Complete Complete

Amount of movement Range less widely Range widely on summer range (except Madison Plateau)

Amount of movement Varies among herd Varies among herd on winter range groups, bull groups, groups, bull and solitary bulls groups, and solitary bulls

Movement beyond A few bulls, SW A few bulls, N&E boundaries corner boundaries, summer; herd groups, N boundary,

Summary:

Population separation One population: Almost separate One breeding pop- Mary Mountain ulation, with winter range designations as Lamar and Pelican

Applies to relationship between Hayden and Pelican valleys.

ter (56%) reflects the animals' fre- except fall, averaged more than quent concentration during this one-third of the diet for the entire season on sites where nearly all the year. Its highest value (46%) in

plant growth is sedge. Grass, sec- spring probably reflects both

ond in quantity during all seasons greater palatability and increased 92 Bison of Yellowstone National Park

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— ^ ~V T3 u 3 w u u -a be c ll 1 w a > o jg Q 1 s £5 J K 2111J D 94 Bison of Yellowstone National Park availability of new spring growth. ance at higher elevations of the Wire rush was taken yearlong, but Lamar area were made by Olde- averaged approximately one-third meyer (1966) and Woolf (1968). of the fall diet. Hayden Valley species are men- Both forbs and browse were tioned by Kittams (1949) and the represented throughout the year Soil Conservation Service (1964). in the bison diet, usually as trace From these sources and informa- items. Forbs (mostly phlox) aver- tion obtained during this study, a aged 3% of the spring diet; north- list of grasses and grasslike plants west cinquefoil averaged 6% of the was compiled according to site summer diet. Although forbs did (Appendix VII). Forage composi- not total a large percentage of the tion information for the thermal forage utilized, they may be an sites used by bison during critical important part of the diet nutri- winter periods (see Use of Ther- tionally. mal Areas) has not been determined. Browse was of least importance quantitatively, forming only 1% of Wet bottomlands, creek banks, the year's diet. Six species were and pond edges support dense identified —four as trace values. sedge growth (mainly Carex aqua-

Dwarf huckleberry represented tilis, beaked sedge, and Nebraska 2% of the summer diet but oc- sedge). Slightly less wet sites sup- curred in only one of the four port a greater variety of sedges, samples. Its presence may be inci- horsetail, wire rush, and grasses dental to the summer use of for- such as sweetgrass, timothy (par- ested areas where it is common on ticularly in Lamar), and tufted the forest floor. Other browse hairgrass. plants shown in the analysis may wintering also be incidental to feeding at a Moist meadows of the valleys of the same particular site. Their possible have some sedges (Carex acuta, C. platylepsis, importance nutritionally is unknown. C. raynoldsii) found in the less wet sites such as swales. Smallwing Forage composition data for the sedge was the most commonly bison use areas represented by the observed additonal species. Horse-

food-habits analysis are limited. tail, rushes, and additional grasses, Descriptions of species composi- particularly bluegrass, are found.

tion for the Lamar Valley are con- Giant wild rye is prominent in tained in Rush (1932b). The Soil Lamar. Conservation Service (1963) and Moist and dry upland sites both Bergstrom (1964) provide some support bluegrass species, Idaho quantitative data. Descriptions of fescue, and needlegrass. On the species composition and abund- drier sites, junegrass and various Habits 95 wheatgrasses occur in most areas; tain brome, needlegrass, wheat- the sedge Carex xerantica is com- grass, alpine timothy, and tufted mon in Lamar. hairgrass are all common. Subal- At higher elevations on moun- pine meadows have fewer sedges tain herbland sites, sedges such as (mainly Carex raynoldsii and Carex raynoldsii and smallwing Hepburn sedge). Grasses are pre- sedge are prominent. Rushes, dominantly bluegrasses and tufted bluegrasses, Idaho fescue, moun- hairgrass. 8 Habitat Relationships

Use of Forage Areas

Observations of bison use of along the Pelican Creek bottoms forage areas indicated preferred where snow depths permitted. In locations and vegetation types and Hayden Valley, some years, the suggested resulting influences on mixed herds were seen almost all the populations. These were most of the time along Alum Creek in apparent in winter. Forage availa- the vicinity of Violet Creek. In the bility did not appear to be a popu- Lower Geyser Basin, the extensive lation-limiting factor most of the sedge meadows of Sentinel Creek, time. Conditions under which for- Fairy Creek, and Fountain Flats age might be a limiting factor were were used most of the time by suggested but not established by most of the animals. Use of these this study. Bison, in turn, influ- sedge areas was facilitated by the enced their foraging areas (see ability of bison to forage in deep Effects on Habitat). Grasses and snow (previously mentioned), and grasslike species which commonly the influence of thermal activity on occur in some forage areas are list- some of the sites (see Use of Ther- ed in Appendix VII. mal Areas). During the winter, most bison Use of specific upland sage- concentrated on sedge sites for brush-bunchgrass areas on the their forage. At Soda Butte in winter ranges apparently varied Lamar, 30 or more bison concen- more from year to year. In 1965- trated at times, and a few to a doz- 66, on aerial observation flights, en bulls stayed all winter long. animals were observed most fre- Elsewhere in Lamar, mixed herd quently on the north side of Peli- use concentrated along Slough can Creek, at the lower end of As- Creek sedge bottoms and in the tringent Creek, and to the west for many sedge swales west of the 2 miles. The next year they were Lamar Canyon. Within the main usually observed on the slopes of or lower Pelican Valley, study re- the southeast edge of the valley, in cords showed that herd use was the vicinity of the old bridge over constant, much of every year, Pelican Creek. A third year they

96 Habitat Relationships 97 were in the east end of the valley. populations or for the higher Only three times during 30 years populations of the past. of ranger ski patrols and once dur- Observations indicated that al- ing the present study were mixed though bison migrations between herds seen at the Mushpots-Mud- winter and summer ranges were kettles area of the upper valley in not caused by forage conditions, winter, although they crossed this less extensive movements were area in spring. In Hayden Valley influenced by changes in plant one year, the herd groups, when growth. During the summer, with not on Alum Creek, ranged the the additional influence of biting north-facing slopes of the hills on insect populations, bison moved the south bank of Alum Creek. on upward on the summer ranges Another year they were located as the spring season reached high- more frequently another mile or er elevations. Movement among more south, on the slopes and the main use areas of swales and knobs in the southwest corner. lush spots was considerable, prob- Such differences in use of specific ably because these places were sites also existed on the Firehole usually small in extent and widely and in Lamar. Presumably, vary- scattered, although numerous. ing patterns of snow drifting, Local movements at all seasons crusting, and melting which affect- appeared influenced by intersper- ed forage availability influenced sion and size of foraging sites. these shifts of use on upland sites. Information obtained during During spring, summer, and the present study did not indicate fall, bison use of forage areas con- population levels at which severe centrated less on any one place or winter conditions might limit the type. Use of sagebrush-bunchgrass forage available from the complex sites increased particularly in the of sedge and upland sites. Present spring, but during all three sea- observations were limited to rela- sons bison were more commonly tively low population numbers and seen on swales and lusher mead- were made during mild and aver- ows where sedge species composed age winters. Observations and much of the vegetation, even at information from the present high elevations. Use of forested study and earlier did suggest that sites for feeding was usually limit- bison numbers were related to use ed to the more open growth and of specific thermal sites during seemed incidental to other influ- extreme winter conditions. Bison ences (rutting activity, shade use of these sites may result from a needs, escape cover, travel, escape combination of temporary forage from insects). At no time did for- limitations on the preferred sedge age appear limited during these and upland sites, the ability of bi- seasons, either for the present son to reach these sites, and the 98 Bison of Yellowstone National Park direct physical influences of pro- mal influence. Thermal activity longed cold or storm conditions. refers to sites where thermal fea- Forage in these sites appeared tures (geysers, hot springs, fumar- quite limited; thus these sites may oles) are located. The ground at be a population regulation mecha- these sites is usually snow-free to nism influencing mortality accord- some extent, and streams into ing to the numbers of bison forced which the features discharge hot to use them and the length of time water may remain as ice-free travel they stay. routes for some distance from the activity. Additionally, there are Use of Thermal Areas places where there may be no thermal features but warm ground Bison utilized wintering sites results in small snow-free areas or which were influenced by the larger areas where snow does not widespread thermal activity in the accumulate as deeply as it would park. The amount of use varied without the thermal influence with the size of the bison group (Figs. 38-41). (solitary bulls, bull groups, mixed One to several bulls used sites of herd groups) and the kind of ther- thermal activity (Fig. 42) more

Fig. 38. Snow-free bison feeding site on warm ground at the edge of Fairy Meadows in the Firehole. Habitat Relationships 99

Fig. 39. The same site shown in Fig. 38, in early summer.

than larger bull groups and mixed Springs, Violet Springs, and Mary herd groups did, but these sites Bay in the Pelican country. But were not used by a majority of more than half of the bulls which such bulls. Scattered bulls were wintered apart from the mixed habitually found at various places herd groups were located where in the Firehole, at the Mud Vol- there was neither thermal activity cano in Hayden Valley, at Soda nor the influence of warm ground. Butte in Lamar, and at satellite Both Lamar and Hayden Valley areas such as Ponuntpa Hot had proportionately more of the

Fig. 40. Site along Alum Creek in Hayden Valley where warm ground causes snow to melt early. 100 Bison of Yellowstone National Park

Fig. 41. The same site shown in Fig. 40, in summer.

total number of the wintering water (Fig. 45). Only in Lamar, of bulls, as discussed previously. In the four main wintering valleys, both valleys, most of the solitary were thermally influenced places bulls and bull groups were ob- little used by mixed herd groups; served apart from any site of ther- thermal activity is least there (ex- mal influence. cept Soda Butte). Herd groups were seldom seen at sites of thermal activity but often used areas of thermal influence, particularly sedge bottoms where snow depths were less (junction of Alum and Violet creeks in Hayden Valley (Fig. 43), Pelican Springs area of Pelican Valley, Lower Geyser Basin areas on the Firehole). They used open streams such as the Firehole River, Alum Creek, and parts of Astrin- gent Creek (Pelican) for travel Fig. 42. Bison bull wintering among active geysers and hot springs. (Fig. 44), and fed on the sedge growth of the banks while in the Habitat Relationships 101

Fig. 44. The Firehole River is open all winter because of an influx of hot water from geysers and hot springs along the banks. Photo by Karl Bittler. 102 Bison of Yellowstone National Park

Fig. 45. Sedge growth along the banks of the Firehole River provides forage for bison and elk moving in the open water.

Total use by all bison of areas in conjunction with the activity of where thermal influence alleviated a few hot springs or fumaroles, otherwise more severe winter con- were of great importance to the ditions involved was more than the bison population during brief but use of thermally active sites. In the critical periods. During the pro- Hayden, Pelican, and Firehole val- longed very cold spells of the se- leys, the amount of use of sedge vere winter of 1955-56, Jim Strad- bottoms with lessened snow ley (1968 pers. comm.) observed depths, and of ice-free streams, mixed herd groups in the scat- indicated that thermal influence tered small, warm areas west of was important in maintaining win- Astringent Creek in the Pelican tering populations. In Lamar, area, in the Mud Volcano area of where winters are comparatively Hayden Valley, and just east of the less severe, the lack of thermal Firehole River (Pocket Basin) in influences may not affect numbers the Lower Geyser Basin (Firehole). of bison which can winter there. During the study, herd groups Observations both before and were seen in these same Astrin- during the study period indicated gent Creek areas of Pelican (Fig. that specific sites of thermal influ- 46) late one winter (1968) after a ence where small, warm, snow- stormy period and presumably free patches occurred, sometimes were there the few other times Habitat Relationships 103

Effects on Habitat

Effects on habitat as observed throughout the study period were considered from two points of view: those which seemed to occur even under low population densi- ties of bison, and those which might have resulted from an eco- logical imbalance and overpopula- tion by bison. Bison caused or contributed to five kinds of impact on their habitat: debarking of trees, formation and maintenance of trails and wallows, trampling of Fig. 46. Bison in one of the scattered sinter rock deposits in areas of small thermal areas west of thermal activity, and alteration of Astringent Creek in the Pelican plant cover. country. Trees which were debarked and even girdled by the rubbing and horning of bison in summer were not scattered throughout the bison they could not be located in the use areas, but occurred in certain usual places. Winters (except localities, apparently favored by 1964-65) were not severe during both the mixed herds and the scat- the study period, and mixed herd tered bulls. In extensive areas of groups were not observed at Mud lodgepole pine forest on the south Volcano nor in Pocket Basin. The side of Hayden Valley (Fig. 47), in areas were not preferred by the groves on the lower end of the herd groups, since use apparently Cache-Calfee ridge, and at a few was restricted to periods of severe sites on the Mirror Plateau, nearly conditions or late winter. Forage every tree had been rubbed to appeared very limited in these some degree. Elsewhere, very areas and the period of use was small groves of trees located far usually very brief—a few days or from the normal summer range of perhaps a week. In spite of very the mixed herds also showed hard limited use, these areas probably use, apparently by one or more of represent the margin for sur- the separated bulls. Rubbing oc- vival of the herd groups in Fire- curred during the period of shed- hole, Hayden, and Pelican valleys ding and regrowth of hair, when during the most extreme winter biting insects were sometimes conditions. numerous, and extended on through the rut. Horning of trees (just west of the park) but that for- by bulls, more specifically associat- est areas were increasing slowly. ed with rutting activity, had even Similarly, the bison might impede, more effect than rubbing (Fig. 48). but not stop, the invasion of the Although many trees survived meadow areas by the forest, which years of this use, isolated trees and appears to be occurring. those near the edges of the forest Wallows, particularly those lo- were often killed. McHugh (1958) cated in places where summering found that in rare cases in Hayden bulls commonly stayed or traveled, Valley the tree line was actually were used year after year. Wallows forced back, but that overall effects were as much a feature of these on reproduction were minor. Pat- areas as were the bison themselves ten (1963) concluded that elk con- (Fig. 49). Even after areas such as tributed to maintenance of an Blacktrail Deer Creek were unin- abrupt ecotone between forest and habited by bison for a number of meadows in the Madison Range years, the depressions left by the Habitat Relationships 105

such sites did not appear to be related to population levels; some of these places were used before the present study (Kittams 1949) and show no change in spite of greatly reduced bison numbers. Bulls were commonly seen every year and at all seasons on some of these sites, which suggested that as long as any bison inhabited Hayden Valley these favored places received heavy use. Revegetation of favored wallows might occur only without a bison population. Trails used by bison, such as the network within Hayden Valley (Fig. 50) and those connecting main use areas such as the Mirror Plateau and Upper Lamar, were also features which appeared only indirectly related to population numbers. These routes were used historically, as now, because of habits and distribution patterns. Areas of thermal activity used by bison, where hot pools and geysers are located, sometimes show Fig. 48. Bison horning effects on a lod- breakage of sinter deposits by gepole pine. trampling. Because the rock deposits form slowly, the effects may be apparent for years. Mixed herd groups used such areas infre-

wallows could still be discerned, quently and for brief periods, ac- although no differences between cording to the severity of winter- the vegetation within and around ing conditions, as discussed pre- the depressions were apparent. viously. Some wintering bulls used When situated on slopes, wallows certain thermal areas throughout sometimes formed focal points of the winter every year regardless of erosion, particularly in the shallow changes in bison numbers. sandy soils of the hills in the south- Locations where debarked trees, west part of Hayden Valley. The wallows, trails, and trampling of presence and continued use of thermal areas were most noticea- 106 Bison of Yellowstone National Park

Fig. 49. Bull bison at a wallow which is used year after year.

ble were in the Firehole-Hayden effects which occurred at locations Valley part of the park. Before the favored by bison for specific activi- present study, during the much ties. The amount and distribution higher bison populations of the of such effects might increase mid-1950s, these effects caused somewhat at higher population considerable concern. The impact levels, but not to the same extent of the presence of bison was ob- as the numerical increase. An as- vious, and may have seemed espe- sessment of such effects would not cially striking because bison (ex- provide an indication of what a cept perhaps a few strays) had desirable bison population should been absent from that area for at be in Yellowstone. least 35 years and had not been Bison effects on plant cover present in any numbers for at least were apparent on foraging areas 50 years. Then, over a span of of the winter ranges where habitat about 15 years, the marks of bison use is restricted by winter condi- habitation became suddenly ap- tions. Observations indicated that parent, and increased rapidly as effects on summer range from use the population expanded into this by the wide-ranging bison ap- uninhabited section. The resulting peared less important than influ- concern was understandable, but ences from climatic factors (late- perhaps exaggerated. melting snow patches, late springs, Observations made during the short growing seasons) and edaph- study period indicated that de- ic influences (slope, soil, expo- barked trees, wallows, trails, and sure). trampled thermal areas were all During the present study, evalu- Habitat Relationships 107

areas of upland (usually steeper slopes and southwest exposures) in the poor and fair condition classes, producing less than 25% and 26- 50%, respectively, of potential or climax vegetation. Soil erosion and disturbance (particularly in Peli- can and Hayden valleys) by animal trampling and rodent activity was noted. Wetlands and subirrigated (a range classification term for some naturally occurring moist sites) lands were in good to excel- lent condition. The condition of these wintering valleys was attributed to use by elk and, particularly in Pelican and Hayden valleys, to winter use by bison. An evaluation of the Firehole was not made by Soil Conservation personnel, but general observations indicated that essentially the same conditions prevailed. The effects which bison had on the vegetative cover of the winter ranges they inhabited, as the above surveys showed, were mostly confined to upland sagebrush-bunchgrass sites. Both the surveys and the present study indicated that the sedge-producing wet bottom-

lands and swales showed little ef-

Fig. 50. A bison trail, one in a network fect. Observations made during connecting the most-used parts the study indicated that bison use, of the Hayden Valley area. particularly by mixed herd groups, occurred most frequently and for longer periods on these wet sites, which were the main ations made of range conditions in source of forage. The condition of Lamar, Pelican, and Hayden val- the less-used upland areas suggest- leys by the Soil Conservation Serv- ed that these sites were particular- ice (1963, 1964) indicated large ly vulnerable to impact and might 108 Bison of Yellowstone National Park remain in such condition in spite extent to which present conditions of varying patterns of use. Cole represent the past. A bison popu- (1969) suggested that free-ranging lation has wintered there annually elk would maintain upland areas since the park was established (and in similar condition, which he probably long before), it has been termed biotic disclimaxes. least disturbed by man (reduc- Information on the quantity and tions), and historical sources pro- composition of the forage re- vide limited information on early sources of the thermal sites used habitat conditions. Jones (1875) by mixed herd groups under ex- wrote: winter conditions has not treme This prairie is the home of great been obtained. Use of these areas numbers of field mice and moles in stress circumstances (which oc- [pocket gophers], which have bur- curred infrequently) rather than rowed up the ground to such an extent that it is traveled over with diffi- by preference suggests that al- culty . though the forage resources appear very limited, the duration The same comment could be made and intensity of use do not permit today, which suggests that the destruction of the vegetation. appearance of Pelican Valley has

Several considerations suggest changed little, regardless of the that the effects of bison use on win- cause of that appearance. If the ter ranges, clearly apparent on cause (bison use) has not changed upland sites, may not be greater appreciably, present conditions in than those which prevailed at the Pelican Valley may approximate time the park was established. those which prevailed at the time First, the habitat of the main win- the park was established. tering valleys (except Lamar) has The extent to which conditions been little altered by the activities resulting from bison use of the of man, although animal numbers other wintering valleys may yet and distributions have been resemble those of early times is less changed. Second, although the clear. In Hayden Valley, range actual numbers of bison which surveys (Kittams 1949; Soil Con- originally inhabited the park area servation Service 1964) attributed throughout the year are not retrogressive changes in plant known, information from this cover on upland sites primarily to study indicated that present num- the effects of bison use. The ab- bers, and those for much of the sence of many bison for nearly park's history, have been less than 50 years apparently permitted a the original populations which trend toward climax vegetation; apparently centered on the var- subsequent repopulation caused ious winter ranges. marked retrogression which may Pelican Valley may indicate the represent reestablishment of con- Habitat Relationships 109 ditions which were prevalent with a more diversified ungulate popu- use by the original bison popula- lation (elk; bighorn, Ovis canaden- tion. Conditions resulting from sis; moose). The extent to which use by bison in the Firehole may be bison use and resulting effects may comparable. overlap with that of other ungu-

In Lamar, present effects of bi- lates on this range is presently son use probably represent more being studied (William Barmore of a departure from early condi- 1969 pers. comm.). Present low tions. Habitat disturbance by man bison numbers contribute minimal has been greater, bison popula- effects on vegetative cover com- tions were maintained in semido- pared with other influences, and mestication for many years, and have much less impact than in his- the area provides winter range for toric times. 9 Suggested Mechanisms of Population Regulation

Bison population numbers have population segments; the need for been regulated by both natural future reductions on any popula-

and artificial means since the park tion segment is less clear. Figure was established. Regulation of the 51, which shows the known Pelican original bison population must Valley wintering bison population have resulted entirely from envi- from 1902 through 1968, suggests ronmental and populational that at least this part of the bison mechanisms. Regulation, to a vary- population has been regulated for ing degree, has been imposed by many years without interference man since near-extermination of by man. Since the time of intensive the original bison. Limited knowl- poaching in the 1890s, reductions edge of original bison population have been made there only twice: characteristics, habits, and distri- 118 bison in 1956, 34 bison in bution, together with application 1965. Following the near-extermi- of ranching methods to the plains nation before 1902, the popula- bison introduced in 1902, has in- tion increased gradually for nearly fluenced subsequent management 20 years. Counts as shown are practices. After 1952, all vestiges probably somewhat low, but of artificial management, except suggest that a fairly stable popula- reductions to control population tion existed for another decade. A

numbers, were eliminated. Reduc- general slow upward trend is evi- tions were continued at irregular dent from the early 1930s to the intervals to compensate for the early 1950s, but the population alterations in natural conditions remained near or below 300 ani- which were the accepted result of mals until after 1952. Between the establishment and use of the then and 1954, when 461 bison park, and settlement of the sur- were counted, there was a marked rounding country. increase. Subsequent low numbers Information from the present by 1957 and thereafter seem inad- study indicates that compensatory equately explained by either re- reductions are not necessary on all ductions or group shifts.

110 1

Population Regulation 1 1

/900 /905 /9/0 /9/5 /920 /92S /930 /Qjf

500

/935 '940 /945 /950 /9S5 /960 /96S /970 re**

Fig. 51. Pelican Valley population numbers, 1902-68.

A complex of environmental differential mortality among sex influences probably is involved in and age classes indicated by trap what appears to be a naturally records. Survival rates of calves regulated population. Emigration during the first year, compared from the Pelican area has not been with the decreased rates among an important factor (see Popula- yearlings and 2-year-olds, suggest- tion Trends) in spite of the occa- ed that calves, perhaps because of sional temporary group shifts. closer association with the cows, Predation and disease, previously were not as stressed by environ- discussed, have been only minor mental conditions. Yearlings and influences. Environmentally influ- 2-year-olds—less closely associated enced factors of low reproduction with a particular adult, and of rates compared with those of other smaller size (particularly females) bison herds, low increment rates in and less social standing compared spite of some increase in new-calf with 3-year-olds—might be at a percentages following recent re- disadvantage, less able to forage ductions, and heavy mortality dur- effectively and less able to travel in ing exceptionally severe winters deep snow. McHugh (1958) ob- appeared most important in Yel- served a dominance hierarchy lowstone as a whole. Presumably, based on sex and age. He noted the same factors apply to Pelican that calves derived dominance as a subunit. from their cows, and that domi- Environmental effects, particu- nance was displayed in feeding larly the combination of low tem- situations and deep-snow travel. perature conditions and snow The stress on subordinate animals, depths sufficient to require consid- as well as aged or otherwise weak- erable efforts for survival, were ened adults, would increase with not measured and were difficult to increasingly severe weather re- observe, but were suggested by the gardless of forage availability for 1 1 2 Bison of Yellowstone National Park — 3

Population Regulation 1 1

the entire population. The rela- cold combined with deep snow as tionship between numbers of ani- observed by Jim Stradley, or in late mals, available forage, and mortal- winter as seen during the study ity did not appear to be direct; period—may determine the lower forage quantity, although affected limits to which the population by snow depth and distribution, numbers drop. exerted effects in combination A comparison of the larger Yel- with the physical stress imposed by lowstone valleys (Table 18) gives snow depth and storm conditions further evidence on which factors at low temperatures. make habitation by bison possible. Figure 51 also shows a level be- In addition to the previously dis- low which the Pelican population cussed wintering valleys, there are has not dropped since the recov- other large valleys in Yellowstone ery (about 1935) from the low of where bison herd groups appar- 1902. Although only 88 were ently were never known, histori- counted in 1957, no attempt was cally or more recently. Extensive made to locate all animals (Jim sedge bottoms are a feature of the Stradley 1968 pers. comm.). Thus, valleys used by bison; additionally, approximately 100 animals may where winter conditions are con- represent the maximum popula- sistently less severe, as in Lamar, tion which could survive the most there are extensive open side hills severe winter, but perhaps a figure of sagebrush-grassland which al- of 100-200 bison better represents low both movement and feeding. a level around which this popula- Where winters are more severe, tion has fluctuated since 1935. those valleys which have bison That bison have survived, and at have either extensive thermal or this population level, in a valley warm areas, or else many small such as Pelican in spite of severe ones among which movement is winters suggests that a margin for possible. Some streams which survival might be represented in remain unfrozen because of an parts of the Yellowstone environ- influx of warm water are an addi- ment which does not occur else- tional feature of most wintering where. areas, as are some river benches The survival factor for bison in or valley side slopes and small parts of Yellowstone may be the hills (sagebrush-bunchgrass up- existence of thermal areas. As pre- land sites) which aid both foraging viously discussed, thermally active and movement. Where too few of areas do not attract large numbers these factors occur together the of bison for the winter, but the use valleys do not now, and probably of certain areas for brief periods never did, support mixed herd particularly at times of prolonged groups of bison. 114

Appendix I

COMMON AND SCIENTIFIC NAMES OF PLANTS

Common name Scientific name

Alpine Foxtail Alopecurus alpinus Alpine Fir Abies lasiocarpa Arnica Arnica spp. Balsamroot Balsamorrhiza sagittata Barley, Meadow Hordeum brachyantherium Barley, Wild Hordeum spp. Blue-eyed Mary Collinsia parviflora Bluegrass Poa spp. Bluegrass, Alpine P. alpina Bluegrass, Canby P. canbyi Bluegrass, Cusick P. cusickii Bluegrass, Kentucky P. pratensis Bluegrass, Sandberg P. secunda Bluegrass, Timberline P. rupicola Cinquefoil Potentilla spp. Cinquefoil, Northwest P. gracilis Cinquefoil, Shrubby P. fruticosa Clover Trifolium repens Dandelion Taraxacum spp. Dwarf Huckleberry Vaccinium scoparium Engelmann Spruce Picea engelmanni Eriogonum Eriogonum spp. Eriogonum, Sulfur E. umbellatum Geranium Giant Wild-rye Elymus cinereus Groundsel Senecio spp. Horsetail Equisetum spp. Idaho Fescue Festuca idahoensis Junegrass Koeleria cristata Lupine Lupinus spp. Mountain Brome Bromus marginatus Needle-and-Thread Stipa comata Needlegrass Stipa spp. Needlegrass, Columbia S. columbiana Needlegrass, Richardson S. richardsonii Onion Allium rubrum Phlox Phlox spp. Pine, Lodgepole Pinus contorta Pine, Whitebark P. albicaulis Pinegrass Calamagrostis rubcscens Purple Onion Grass Melica spectabilis Pussytoes Antennaria parvifolia Raspberry Rubus spp. Common and Scientific Names of Plants

Common name Scientific name

Red Dogwood Cornus stolonifera Kusn Juncus spp.

Rush, Long-styled J. longistylus

J fpnuK I\ Ll j 1 1 , JIC11UC1

Rush Wire J. balticus Sagebrush Artemisia spp.

. l. Ll JU I- 1 1 La La Sagebrush, Fringed A. frigida Sedge Carex spp. a C. acuta

L>. aUCl la C. aquatilis C. athrostachya C. nova C. platylepsis C. raynoldsii

C. xerantica Sedge, Beaked C. rostrata Sedge, Hepburn C. hepburnii Sedge, Nebraska C. nebraskensis crp Sf»H Oval riparl V ' . l(,i7LiVLJla Sedge, Silvertop C. foenea

Sedge, Smallwing V ' . M/H i UUILJ CI

Sedge, Valley r am\~vjla crp AA/r»nllv V > . tall UizliiLJja

jci vii^cucri l y f\lllClalH~lllCl Mjn.

Snikf -spH of J .in'l l/dl Jj HUH 1 Ujlatilrfl

1 lit l v /l_ 1 1 1 v iyt_iC/I aLa Timber Oatgrass Danthonia intermedia

1 HHUIII y illlCLllll Ul alCllbC Timothy, Alpine P. alpinum

TiiftfHX UlltU 1Haircrrass1 CI 1 1 tZl ajj i-^CTjCl JcaiJl LMoia \~aCjLJlL\Jja

WpsrprnIttJlV-l 11 URiilrnsViUll UJU k7LvirniK11 L/tUj aLUlUJ^/"iifiic

vv 1 1^ el I til a j j Agropyron spp. Whpatcrrass Rlupbunch A. spicatum Wheatgrass, Bluestem A. smithii Wheatgrass, Slender A. trachycaulum Wheatgrass, Thickspike A. dasystachyum Willow Salix spp

a Not listed in Booth (1950), but determined by him (1968 pers. comm.)

521-650 O • 73 - 9 116

Appendix II

SUMMARY OF BISON REPORTS PRIOR TO 1903, YELLOWSTONE NATIONAL PARK AND VICINITY

Source Date Report

Raynolds 25 June 1860 crossed Low Pass from Henry's Lake to (1867) the Madison (west of Yellowstone National Park) "We have seen one band of buffalo

among the hills, ..."

DeLacy 7 Sept. 1863 eastern side of Shoshone Lake "through (1876) scrubby pines, without underbrush. There were many game trails made by the wood buffalo, whose tracks appeared numerous and fresh. We did not see " any ...

Haines 1860s quotes local newspapers of the period as (1968 pers. saying there was a herd of bison in the comm.) Snowy's (north of park, part of Absarokas).

Potter 1867 south end of Yankee Jim Canyon (north

(1962) of Gardiner, Mont.) "That whole flat would be covered with buffalo."

" 'all this buffalos'"

Cook, et al 3 October 1869 reference to Buffalo Pool, Lower Geyser (1869) Basin (Firehole area) "in one spring we " saw the entire skeleton of a buffalo . . .

Henderson 21 June 1870 Buffalo Plateau (north edge of park) (1870) "thousands of buffalo quietly grazing." 27 June 1870 upper Buffalo Creek (north edge of park) "All game plenty—buffalo, ..." 2 July 1870 Lake Abundance (just beyond northeast corner of park) "Thousands of bear, elk, buffalo, and deer." 17 July 1870 N. Fork of Clark's Fork (Broadwater River, east of northeast corner of park) "several beautiful parks, full of buffalo,... 22 July 1870 Cache Creek (Lamar area)

"thro buffalo, elk & bear ... all very tame." 24July 1870 Specimen Ridge (north edge Mirror Plateau) "Buffalo ..." Bison Reports Prior to 1 903 117

Source Date Report

8 August 1870 summit between Buffalo Cr. and Hell- roaring (north edge of park) "Saw several buffalo." 9 August 1870 head of Middle Boulder River (north of Park) "Thousands of buffalo, ..."

Doane 18 Sept. 1870 Old Faithful (Firehole area) "numerous (1875) fresh signs of buffalo ..."

Barlow and Heap 2 August 1871 Lower Geyser Basin (Firehole area)

(1872) "Across the plain to the west . . . mud

springs in ravine . . . tracks of deer, elk and buffalo ..."

Blackmore 1872 Lamar

(1872) "B.H. informs me that this valley is a favorite resort of the mountain buffalo or bison. The hills on the left were the last place that he saw the buffalo this spring followed them for nearly 30 miles and captured during his hunt 7 young calves... informs me that the M.B. congregate in bands of from 5-30 rarely more altho he " has seen 50 ...

LeHardy 1873 "The valley of the East Fork [Lamar] (1873) (about mid-August) extends Eastward very straight for many

miles, the floor . . . deeply covered with grass. In this grass we saw in the distance quite a number of Buffalo."

Jones 1873 found bison bones embedded in soil at (1875) the bottom of a cave at Mammoth

Dunraven 1874 general locale of Yellowstone National (1876) Park. "On the little prairies, open glades, and sparsely wooded slopes, grazes the small mountain bison or buffalo, whose race has also nearly vanished from the scene; ..."

Grinnell 1875 "The so-called 'Mountain Buffalo' was (1876) abundant in the Yellowstone Park."

Supt. Annual 1875 "scores if not hundreds of moose and Report (1877) bison were taken out of the park in the spring of 1875, ..." 1 1 8 Bison of Yellowstone National Park

Source Date Report

1877 refers to the triangle of land with the East Fork (Lamar) as the base, extending south 50 miles to the head of Yellow- stone Lake (Mirror Plateau, Pelican)

"Here is still a herd of three or four hundred of the curly, nearly black bison or mountain buffalo."

Holmes 1878 Twin Buttes (Firehole area) "there are (1878) some upland parks in which there are buffalo signs (the Mountain Bison)."

Raymond 1880? "whitened skeleton of a mountain (1880) buffalo ..." (in a hot pool — Firehole area)

Supt. Annual 1880 "Bison or Mountain Buffalo" "Bison, so Report (1880) called, in the Park, are somewhat smaller, of lighter color, less curly, and with horns smaller and less spreading than those of the bison that formerly inhabited the great parks of Colorado. They have also smaller shoulder humps, and larger, darker brisket wattles. They differ materially from the buffalo of the Great

Plains, being more hardy, fleet, and in- telligent; their hides also are more valua- ble for robes, as they are darker, finer, and more curly; and these animals are, in

all probability, a cross between the two varieties just mentioned. "There are about three distinct or separate herds of bison within or adjacent to the Park. [north edge of parkj

"The first, numbering about two hundred, pasture in summer in the valleys of the Crevice, Hellroaring, and Slough Creeks, and the mountain spurs between them, descending, with the increasing snows, to winter in the deep, sheltered grassy valleys of the East Fork [LamarJ of the Yellowstone and Soda Butte, and as the snows melt, accompanied by their young, returning to their old haunts. [Mirror Plateau and Upper Lamar] "The second, numbering over one hundred, summer in the elevated and abruptly Bison Reports Prior to 1903 1 19

Source Date Report

broken, little-known section of the Park, extending from the Hoodoo region to the Grand Carion, and from Amethyst Moun- tain to Pelican Creek, near the foot of the Yellowstone Lake, and winter occasionally upon the East Fork [Lamar] of the Yellowstone and on Pelican Creek. Their other winter haunts are unknown, [west side of park] "The third herd, numbering about three hundred, roams in scattering bands. This season they were discovered upon the Madison Plateau and Little Madison River. Their winter haunts are unknown,

though it is probable they are on the Pacific side of the Continental Divide,

and, if so, they are not permanent occu- pants of the Park, and are therefore likely to be slaughtered by advancing settlers. "most keen of scent and difficult of ap-

proach of all mountain animals."

Yount 1880 "Here I purpose wintering [junction Soda (1880) Butte Cr.-Lamar River] so as to protect the game, especially elk and bison, in their sheltered chosen winter haunts, from the Clark's Fork and other miners."

Yount 1881 [north edge of park] (1881) "The Slough Creek and Hellroaring bands of bison did not venture near the cabin until February, nor did those of Amethyst

Mountain at all; ... I found . . . that a small band of bison wintered on Alum Creek [Hayden Valley] and another on the South Fork [Firehole River] of the Madison River; ..."

Supt. Annual 1881 Mary Mountain area "It also greatly ex- Report (1881) tended our knowledge of the fire holes in those regions, and afforded proof positive that a band of bison wintered there, at an elevation of nearly 9,000 feet." 1 "

120 Bison of Yellowstone National Park

Source Date Report

Bozeman 11 Jan. 1883 "at least one band of bison, containing Avant-Courier four hundred ..."

(1883) 22 Feb. 1883 There is a reference to the employment of hunters and meat contractors by the Park Improvement Company, refers to Lamar area

"Mammoth . . . Feb. 16 . . . Hunting in

the Park has been stopped . . . parties . . .

contract for Eaton & Co. . . . out, being unable to get the meat through from

Soda Butte . . . deep snow . . . brought

out a fine lot of buffalo meat . . . hunters

and meat contractors were ordered in . . . in hot water."

Pierrepont 11 Sept. 1884 toward Lake Abundance from Slough (1884) Creek (north edge of park) "Five miles to the eastward they ran upon a herd of buffalos numbering about a hundred and

. eighty, out of which they killed seven . .

Hague 1884 "In 1884 I estimated the buffalo in the (1893) Park at 200; ..."

Livingston winter "the herd of bison or mountain buffalo Enterprise 1884-85 that has long inhabited the Yellowstone (1885) March 7 Mountain slopes and valleys was seen to number two or three hundred in the Park this winter." 12 Dec. 1885 quotes New York Sun—George Bird Grinnell "There are, to my positive knowledge, not

more than 700 bison . . . left . . . About

180 are in Yellowstone ... I have heard that twenty head were killed in Yellow- stone Park by a party of English tourists." 19 Dec. 1885 claims from a hunter "well posted" that there are 2 bands in the National Park— of 40 on Souce (probably Slough) Creek and 90 more or less between the forks of the Madison—supposedly some of the 40 were driven out of the park by use of explosives, and killed. Bison Reports Prior to 1 903 121

Source Date Report

Supt. Annual 1885 "The game in the Park had been shot with

Report (1885) impunity and marketed at the hotels ... I succeeded in a measure in breaking up the

wholesale slaughter .... There is some- where in the neighborhood of two hundred bison in the Park, ..."

Supt. Annual 1886 "stopped the wholesale slaughter of Report (1886) game ..."

"From the reports . . . abundance of game [including buffalo] ..."

Supt. Annual 1887 "A small number of buffalo still remain

Report (1887) in the Park, but ... I am unable to state

their number with any . . . accuracy. My

impression is that . . . they will not ex- ceed one hundred in number. They are divided into three separate herds. One of these ranges between Hellroaring and Slough Creeks; in summer well up on these streams in the mountains, outside the Park limits, and in the winter lower down on small tributaries of the Yellow-

stone, within the Park. . . . this herd . . .

doubtful if it now exceeds some twenty

or thirty in number. . . . Another herd ranges on Specimen Mountain and the

waters of Pelican Creek. . . . variously estimated at from forty to eighty. A traveler on the Cooke City road claimed to have counted fifty-four near the base of Specimen Ridge. A scouting party

which I sent out during the month of May found but twenty-seven head of this herd,

with four young calves . . . The third herd ranges along the continental divide and

is much scattered. A band of nine or ten from this herd was seen several times this spring in the vicinity of the Upper Geyser

Basin. ... It is practically certain that none have been killed within the Park limits during the past two years, ..." .

1 22 Bison of Yellowstone National Park

Source Date Report

Supt. Annual 1888 "During the early . . . winter . . . desira- Report (1888) ble ... to secure some accurate information concerning the winter haunts of the buffalo .... "The herd of buffalo which had passed a portion of the previous winter along Specimen Ridge was not encountered, and the only buffalo encountered on the

trip were three in Hayden Valley. . . Early in April ... a band of buffalo were located in Hayden Valley and along Alum Creek. ... a herd of buffalo numbering at least one hundred had passed the winter on the divide between the waters of the Madison and Yellowstone Rivers and in the adjacent valleys. Numbers of these animals have been seen during the spring

along the Fire Hole River and its tributaries, and extended investigations have shown that they range in considerable numbers from Alum Creek, in Hayden Valley, across the divide between the waters of the Yellowstone and Madison Rivers and the Continental Divide to Fall River Basin, in the southwestern part of the Park. From the numbers seen and from the quantity of 'sign' observed over an extended area, the number of these animals that range in this portion of the Park can be estimated at not less than two hundred .... The large number of young calves and yearlings which have been seen

leads to the belief that a natural increase is in progress ....

"During the past two years, . . . but little game has been killed ....

"Hunters, stimulated by the high prices offered by taxidermists for specimens, are now lying in wait beyond the borders of the Park ready to pounce upon any un- fortunate animal [ref. to bison] which

may stray beyond its limits." Bison Reports Prior to 1903 123

Source Date Report

Supt. Annual March 1889 "to visit the warm-spring basins on the Report (1889) east side of Yellowstone Lake, for the purpose of ascertaining whether or not they were the winter resorts of the

buffalo. These basins, . . . well-nigh un-

approachable, except when the ground is

frozen and covered with deep snow, . . . successful in locating the buffalo in their haunts of the previous winter near the hot-spring basins on the divide between the waters of the Yellowstone and Madi- son Rivers. Although no buffalo were

seen east of the Yellowstone, it was evident from the abundant signs that they habitually frequented the hot-spring basins in this locality, some of the signs being quite fresh."

Supt. Annual 1890 "I have no reason to believe that a single

Report (1890) animal has been destroyed. . . . First in

importance, . . . comes the buffalo.

. . . enumeration . . . impossible. ... In the summer season they are broken up into small bands and scattered over a wide area of timber-covered mountains. ... In the winter the deep snows drive them to the open country for food. They are then found in large herds."

Supt. Annual 1891 "Poachers"

Report (1891) "So long as there is no law within the Park for the prevention of hunting and trap-

ping, it will be a most difficult matter to break them up.

"I am satisfied that both hunting and trap-

ping are carried on . . . from over the western border.

"I learn of three or four buffalo heads

that have been mounted in Bozeman, ... I

doubt not all of these were killed within the Park, or very close to the line without

it. ... fine ones are held at $400 to $1,000." 124 Bison of Yellowstone National Park

Source Date Report

May 1891 "I have abundant evidence, however, that the buffalo ... are on the increase. Some tourists who went through the Park in May saw a herd of about 30, with several small calves, near the Trout Creek lunch station."

July 1891 "In July I sent Wilson out to . . . the west

line . . . found two small bands of about 30 each, one with 12 or 15 calves; in addition he saw several single ones and

small bunches. I do not think it is exag- geration to say there are 200, and probably there are 400, within the Park, and that they are thriving and increasing."

Hague winter 1891-92 "the grazing-ground in Hayden Valley (1893) was visited by a snowshoe party, who

counted the scattered bands, . . . groups were generally small, and each contained a goodly number of calves. They numbered by actual count nearly 300, but

there is no means of knowing what proportion of the Park buffalo were then gathered here."

Supt. Annual 1892 "I was informed that one Pendleton, a Report (1892) butcher and poacher from Cooke City, had captured two buffalo calves on specimen range, and had taken them across

the north end of the Park, . . . "there are certainly not less than four hundred here; of these about 20 percent were calves last year. This year, also, the calves seem numerous and prosperous. The great value placed upon them by sportsmen and taxidermists makes their protection difficult, ..." Bison Reports Prior to 1 903 1 25

Source Date Report

Hague 1893 "That buffalo were among the animals (1893) inhabiting the Yellowstone Park was known in the early days of its history;

. . . The Park buffalo may all be classed under the head of mountain buffalo, and even in this elevated region they live for the greater part of the year in the timber.

. . . their habits are quite different from

. . . the buffalo of the plain, and it is most unusual, save in midwinter, to find them in open valley or on the treeless mountain slope. They haunt the most in-

accessible and out-of-the-way places, . . . living in open glades and pastures, the oases of the dense forest, often only to be reached by climbing over a tangle of fallen timber .... the rapidity of their

disappearance on being alarmed . ... It

is surprising how few buffalo have been seen in midsummer, even by those most familiar with their haunts and habits. They wander about in small bands in such unfrequented country as the southern end of the Madison plateau, the Mirror plateau, and the head of Pelican Creek, and on the borders of that elevated tableland known as Elephant Back. In winter, leaving the forest, they feed over the slopes of Specimen Ridge, and in the open Hayden Valley.

"It is not likely that there ever were many buffalo in the Park, ... If they ever roamed over this country in large herds, evidence of the fact should be apparent

by well-trodden buffalo trails, which no- where form a feature of the Park plateau.

. . . They occasionally wander beyond the Park Borders into Idaho and Montana with the first fall of snow, returning to their mountain homes with the approach of spring." 126 Bison of Yellowstone National Park

Source Date Report

Supt. Annual 1893 "As the game diminishes in the adjacent Report (1893) States, professional hunters and trappers become more bold and more active.

Montana, Idaho, and Wyoming all have stringent game laws, but in spite of them the game grows rapaidly less. ... A

stringent law, with severe penalties, is one of the most urgent needs of the

Park. . . . Confiscation of the outfit,

under existing regulations, has but little

effect, as the outfit is generally worthless. "I have pretty reliable information that

about a dozen buffalo were killed last

winter, and it is not improbable that even more shared that fate. The heads of these were mounted .... "The buffalo have been seen often during the year, and they appear to be doing

well. In all the herds a fair proportion of

calves is found. Those killed have been mostly bulls, so the capacity of the herd for increase has not been diminished. Late in June a herd of fifty to sixty crossed the road from west to east near the River- side Geyser. Thirteen calves were counted.

They were . . . very tame, and not the least scared by the soldiers who went among them. The estimate of four hun-

dred placed on their number last year is surely not too high."

Hough spring 1894 "We counted 75 to 85 head of buffalo in

(1894) Hay den this trip. . . . Sergt. Parker makes the Hayden and Nez Perce district buffalo 81 head. Capt. Scott counted 103 head in Hayden Valley one day three weeks ago. One band of 6 and another of 7 head were seen in the Pelican country,

. . . We saw three head in Nez Perce Valley." Hough states that Howell was killing cows and calves, and probably killed, during

the winter, more than the 1 1 known killed at his capture in March, as he had been in Pelican since September. Also Hough states 19 were killed SW of the Park by Indians, fall '93; that 7 other Bison Reports Prior to 1903 127

Source Date Report

heads were offered to a Bozeman taxi- dermist; that 6 or 8 dead bison were found in Hayden Valley, "John Folsom discovered ten head more of dead buffalo in that same part of the country;" and that "I have track of several other heads." "I think forty buffalo have been killed

this fall and winter, and no one knows how many more." "The buffalo do sometimes cross the divide about where we did, and work between the hot country of Mary's Moun-

tain and this sheltered little valley. They have not wintered on the west side of the divide in any numbers for a considerable time. "wild wall of mountains which we saw to the north of the Yellowstone—so desolate and forbidding that even now .... there may be a few head of bison left over

beyond the Bison Peak — . . . . "I do not personally believe there are over 150 buffalo left alive in the Park."

Supt. Annual 1894 "not able to report any diminution of Report (1894) poaching ..." (describes Howell poaching case, with Howell caught killing 5 bison in Pelican, and his cache of 6 additional heads).

"The dead bodies of 1 3 bison have been

discovered in their winter range. . . . convinced they perished from natural causes.'

"Buffalo have been more carefully watched and more accurately counted than ever before. After deducting the

losses from all causes, I feel disposed to reduce my estimate ... to 200, ... A few were seen in their winter range as late as the middle of June, and these had calves with them."

NOTE: Garretson (1938) states that during the winter of 1893-94 most of the buffalo were on the Madison Plateau, that 76 head were killed on the west side, and 40 head in the Gallatin valley. He states that no more than 20 could be counted thereafter. He cites no source for his statements, and while the poaching was undoubtedly heavy that year, neither the losses nor the population figure afterwards were stated as fact by any of the recorders of the time. 128 Bison of Yellowstone National Park

Source Date Report

Marble no date mentions Dick Rock (of Henry's Lake, (1932) west of the park) catching 5 calves.

Murri no date reference to Dick Rock getting his buffalo (1968) calves in the Bechler Meadows in early spring, known to have gotten a pair.

Hofer approx. "Hunters from the West Side were getting (1927) 1894 or 1895 calves in the early spring and heads in the winter. From near Gardiner three young fellows killed a number in the basin. These were the ones we found

when I was with E. Hough ..." (some of those presumed dead of natural causes).

Supt. Annual 1895 "The act of May 7, 1894, seems to have

Report (1895) had . . . effect upon the poachers . . . those of the north, the east, and the south

sides have nearly . . . ceased .... I can not say as much for the Idaho border. ... So long as the only herd of wild bison

now existing in the United States is on

the border of this State, . . . inquiry into various rumors of the killing of bison, either in the Park near the Idaho line or

across it . . . convinced me that this last

remaining herd is in danger of extinction

by these people. ... I have good evidence of the killing of at least ten less than two

years ago . . . prior to the passage of the

protection act, ... I have undoubted evidence of the capture of three calves this spring by a resident of Henry's Lake.

. . . There are rumors of a herd of nearly one hundred having been seen in Idaho outside the Park within the last two or three months. [Comments that there was less snow than before known, that the large game could pass at will.] "the bison that have heretofore wintered in the Hayden Valley were not massed there this year. The most seen there in

a single bunch . . . was about thirty. Small herds of from three to four to ten were seen in widely separated localities Bison Reports Prior to 1 903 1 29

Source Date Report

where they have not usually wintered. I feel sure that many of them did not leave their summer range along the Idaho line,

[undetermined losses] . . . but I fear that

their number has not increased, . . . esti-

mate . . . two hundred still remain."

Supt. Annual 1896 "I . . . organized three parties for opera- Report (1896) tions against the merciless freebooters of

the Henry's Lake country. . . . The ground covered by the buffalo in their summer range was most thoroughly gone over. Carcasses, ... of about ten buffa-

loes were found, . . . One party of

poachers was encountered, ... I obtained

information . . . buffalo scalps for sale in the city of Butte. "For some reason the main herd did not winter in Hay den Valley as usual, and on the extensive scouts made by my order during the winter months only about a

dozen in all were seen. They were scattered singly and in small bunches over a

large portion of the Park. Within the last month [July] one party reported a small

bunch of 3 in one place, and of 1 2 in another. A second party reported a bunch of 3 in a valley in a distant part of the park, and tracks of a herd of 8 or 9 more, but this herd was not seen. From

reports received, I feel confident that the majority wintered in the extreme southwest corner of park, in the Falls River

[Bechler] meadows; and I also feel sure that there are now a considerable number

east of the Yellowstone River. . . . fair certainty of the existence of 25 or 30, and possibly of 50."

Snake River 21 Aug. 1897 "By way of Summit Lake. Saw sign of Monthly report about 20 buffalo ..." (Madison Plateau)

Whittaker 14 Nov. 1897 sign of 5, Mary Mountain area (Hayden (1897-99) Valley)

18 Nov. 1897 sign of 2, Astringent Creek (Pelican Valley) 1 30 Bison of Yellowstone National Park

Source Date Report

Supt. Annual 1897 "game, buffalo excepted, is increasing.

Report (1897) "The number of buffalo is estimated at 24. "the buffalo remaining in the park are now scattered in very small herds at a number of points far remote from each other. They are mostly in rough rugged

regions, . . .

"But very few buffalo have been reported this season. The scouts, however, seldom see much sign in the summer, and now the few remaining buffalo are scattered and range in the most remote and inaccessible

parts of the park in summer. I am confident of finding 25 this winter, when the snowshoe season sets in, and hope there are nearly double this number in the park. Since Idaho has forbidden the

killing of buffalo ... I have strong hopes

. . . protect them from further slaughter by poachers." The section containing instructions to sta-

tions recognizes known buffalo haunts as: Mirror and Lamar, Hayden Valley, and the Firehole area.

Soda Butte 19 Feb. 1898 reports wild buffalo Station Record

Morrison Feb. 1898 refers to Mirror Plateau "across to Broad

(1897-98) Cr up it to hot springs near Fern Lake . . . Ponuntpa Springs to look for buffalo. Found numerous signs of buffalo all around the spring and on both sides of Sour Cr. after followed them down Sour Cr. to where a hot creek came down from a hot mountain on the north which they went up, and a close examination of the

trail . . . [the trail was not made in single

file but band was spread out] I estimate the band as follows 4 calfs, 8 bulls, about 8 to 9 cows, but think some of the signs

which I took for cow signs may have been

2 yr. old bulls. In all 21 head. Ponuntpa

Springs is an ideal wintering place for the

band which is there as there is no snow Bison Reports Prior to 1 903 131

Source Date Report

to speak of on the flat which is about a

mile long and 3/4 wide and is covered with hot springs and hot creeks ..."

11 April 1898 sign, estimate of 3, 4 miles north of the Upper Basin, Firehole area

Lake 21 June 1898 old sign—hot formations on Mary Mt. Station Record

Morrison July 1898 "head of Pelican Cr went west to a small

(1897-98) creek that flows in to Broad Cr . . . down Broad Cr about 2 miles thence NE. to hot springs on Shallow Cr up Shallow Cr to Wapiti Lake thence east to camp. Saw signs of 3 buffalo fresh 2 on the small creek that flows into Broad creek and one at Wapiti Lake."

7 July 1898 "left . . . head of Pelican Cr went down it

5 miles made camp . . . went over to Fern

Lake around it to head of Sour Cr down it

then followed buffalo trail fresh over ridge

to Broad Cr, up it to Fern Lake and on to Tern Lake ... to camp. Saw one buffalo jumped 5 buffalo near ford of Broad Cr followed them to Fern Lake where we saw the one was on one of the heads of Sour Cr. an old bull. Around Ponuntpa Springs there were fresh signs of the band

I saw there last winter." 8 July 1898 5-6 buffalo wintered near forks of Pelican Cr., fresh signs

Lake 27 July 1898 one bull buffalo on top of Mary Mt. Station Record 14 Aug. 1898 buffalo signs near headwaters of Raven Cr. (Pelican area) supposed to have been made within the last 20 days—quite a bunch of buffalo hair was found at outlet of White Lake

Morrison 12 Sept. 1898 signs 1 bull 6 mi from W boundary (1897-98) 13 Sept. 1898 West Boundary headed for Summit Lake

"3 m. east of bound, near a little spring saw where 5 buffalo had bedded over night, probably 2 bull a yearling and 2 cows."

521-650 O - 73 - 10 132 Bison of Yellowstone National Park

Source Date Report

Whittaker 30 Sept. 1898 a trip was made up the Lamar to Cold Cr. (1897-99) and Mist Cr., over the divide to the head of Willow Cr. (Mirror Plateau area) and down Raven Cr., up to Pelican, to Broad Cr. and return to Pelican "will make special report on buffalo"

Morrison 10 Oct. 1898 Mirror Plateau area (1897-98) "fresh trail of 2 buffalo at head of Willow Cr. they came down Mist Cr. to the

mouth . . . evidently a cow and a yearling from the tracks ..."

Whittaker 12 Oct. 1898 refers to Mirror Plateau area "but (1897-99) after riding around the entire summer

range i could not find any sign of them

met Scout Morrison . . . presume they

have all left their summer range on Flint and moved to either the head of Pelican

Creek or Willow Creek where i saw some ." sign of them on my last trip . . (see date of 30 September 1898)

Burgess 18 Oct. 1898 Bechler area one, track (1898-99) 19 Oct. 1898 "went to [Bechler] River saw 2 ." year old buffalo tracks . . "tracks of about 6 B They had been made 6 or 7 days ago." 20 Oct. 1898 Firehold to Fountain "saw the Buffalos had been going along the river to the L[one] Star Geyser." 10 Nov. 1898 Trout Cr. to head of Nez Perce Cr. "I found two Buffalo tracks one Bull and cow" 13 Nov. 1898 "Then to East Fork of Pellican, where

I saw the tracks of one buffalo." 23 Nov. 1898 east side of Hayden Valley "Went East to Forest Springs, found old signs of Buffalios ... to worm formation at head of Moss Creek, found some fresh Buffallo tracks going

South . . . and down in sour creek

where there ii quite an opening there

I found where 4 Buffalos had beded the

night before, from there I went to . . .

Cotton grass and Sour Creek I saw 2 old Bulls one laying down they were very wild, and ran back toward sour creek." Bison Reports Prior to 1 903 133

Source Date Report

Supt. Annual 1898 estimates 50 yet in the park

Report (1898) "This is about the only wild herd in the United States, and steps should be taken to prevent the extermination of this ." herd from the evils of inbreeding . .

Burgess 10 Jan. 1899 refers to Mirror Plateau area (1898-99) "up East forks of Estringent [Astringent Creek] to Head of Bluff

Creek. Then to White Lake. I saw two Buffalos and a Great Many tracks, then went to Tern Lakes on the East side of the lake saw four Buffalos Then we went to Fern Lake. Saw 3 Buffaloes on the northwest End of Lake." 11 Jan. 1899 "went up middle Estringent, over White Lake to head of Sour Creek, on this

Creek I saw 15 Buffalos 12 old one and 3 calfs. went down sour creek On this same trip, no sign was found in Hayden Valley.

6 March 1899 "... 2 Buffalo . . . wintering on snake river." 9 April 1899 "went to Estringent Cabin" 10 April 1899 "I looked for the Buffalos. saw 20" 14 April 1899 "went to Trout Creek one buffalo on Crater Hill" 15 April 1899 "went to Fountain 5 Buffalos on Central Plateau"

Whittaker 12 May 1899 "saw one Buffalo near the Base of (1897-99) Hell-Roaring Mountain about a 4 year ." old . .

Lake 1 June 1899 buffalo sign at Mary Mt. Station Record

Whittaker 15 Aug. 1899 "to the headwaters of Deep Creek and (1897-99) flint creek on the mirror plateau to look for the Buffalo, could not see any but ." found numerous sign . . 1 34 Bison of Yellowstone National Park

Source Date Report

Holt 23 Sept. 1899 Snake River to Lake .*' (1899-1901) "fresh signs of two buffalo . . 8 Oct. 1899 "Buffalo passed within sight of ." camp . . (Thorofare area) 26 Nov. 1899 Ponuntpa area, Mirror Plateau "no fresh signs of Buffalo, found skeleton of calf."

Supt. Annual Report 1899 "it is not known how many there are (1899) left or whether or not they are increasing. I shall try and find out this winter as to their number. One of the scouts saw twenty-six last spring, and

signs were seen of others. It is probable that there are fifty or more."

Supt. Annual 1900 "Twenty-nine head of buffalo were Report (1900) counted by scouts last winter, and there were possibly 10 more in the park that were not seen. Unless stations are located near the two southern corners of the reservation and the force of scouts increased the buffalo will be exterminated in a few years. With that addition to the

facilities for protection they can be pre- served and will increase."

Supt. Annual 1901 "it has been impossible ... to ascertain

Report (1901 accurately the number of buffalo . . .

but ... as soon as the snow falls, . . . The buffalo are now protected by the laws of Wyoming, Idaho, and Montana,

and it is now possible that the small herd remaining in the park may increase,

though it may be necessary to introduce some new blood in this herd, and pos-

sibly it may be well to start an entirely

new one and to keep it under fence, turning the animals loose gradually as

the herd increases. From what I can hear

I do not believe that there are more than 25 buffalo left in the park." (One bull was killed in Jackson Hole.)

Lake 8 Dec 1902 patrolled to Pelican Country,

Station Record 1 buffalo Bison Reports Prior to 1 903 135

Source Date Report

Supt. Annual 1902 "In addition to the large corral that Report (1902) has been constructed near the Mam-

moth Hot Springs, a small corral . . . on Pelican ... to capture therein the

few remaining buffalo . . . During the past winter ... 22 of these animals on the head of Pelican Creek, and there are probably a few more that we were un-

able to find. This herd is exceedingly wild, and will probably never increase in size, and may possibly die out com-

pletely. It is thought that we can catch

up some of the young. . . .

"It is our intention to feed and handle the new herd of buffalo in the same ." manner as domestic cattle. . . 136

Appendix III

REPORTS OF WILD BISON 1903-19, YELLOWSTONE NATIONAL PARK.

Source Date Report

Lake 19 Jan. 1903 returned from Pelican Station Record 15 buffalo

15 Feb. 1903 Pelican country 1 buffalo (main valley)

26 Feb. 1903 from Pelican 1 9 buffalo

24 Mar. 1903 from Pelican seen 1 7 buffalo 25 Mar. 1903 Pelican 19 buffalo

12 May 1903 "from Pelican Country . . . Had 2 Buffalo bull calves on toboggan drawn by dogs. Saw 16 old buffalo and 3 calves."

Supt. Annual spring 1903 2 calves captured from wild herd Report (1903)

Lake 4 April 1904 located one buffalo at the hay stack Station Record (Pelican)

end April Scouts—Pelican Valley—"seeing 1 1 Buffalo 5 cows and 6 bulls no calves saw 6 dead ones"

Superintendent's 6 May 1904 party that went out for buffalo calves re-

Journal, 1903-21 port finding as follows ... 1 1 live buffalo

5 dead buffalo—4 old ones and 1 yearling (additional report of one old bull dead between Lake and Thumb refers to one of the three Goodnight bulls which was turned out) 18 May 1904 party returns, having captured one female calf on the head of Sour Creek; they saw twelve live buffalo; men at Canyon station saw two in Hayden Valley

Supt. Annual spring 1904 remnant located on the head of Pelican Report (1904) Creek, "three calves have been

caught up from the wild herd . . . Two

of these are males and one is a female." (the two males were those caught the previous year)

Supt. Annual 1905 "now about 30 of these animals left, Report (1905) ... on the head of Pelican Creek."

Supt. Annual probably sign of 15, Mirror Plateau and Specimen Report (1907) summer Ridge; signs of 6, Madison Plateau. Wild Bison 1903-19 137

Source Date Report

Aug. 1907 4 seen in Hayden Valley total estimated to be 25

Scout Monthly I April 1908 2 bull buffalo, Pelican Valley (near Reports (1908) Raven Creek)

13 April 1908 followed buffalo trail up Lamar to mouth of Mist Creek, saw 10 buffalo, 2 of them yearling calves 16 April 1908 sign as far down the Lamar as Miller Creek where buffalo had been feeding

13 July 1908 9 including 1 calf on upper Lamar 7 Sept. 1908 "Patrolled west to Buffalo Lake, then

(approx.) south to 1 miles . . . saw . . . signs of buffalo" (southwest boundary) 16 Sept. 1908 patrolled northeast to Mist Creek and camped. 18 miles Saw 20 wild buffalo (apparently at the Mushpot-Mudkettle area on Pelican Creek)

9 Oct. 1908 1 1 seen (on trip through Willow-Mist- Upper Pelican Creeks of the Mirror Plateau) II Oct. 1908 saw 7 head buffalo at Pelican Bridge (this report, as well as later ones for the immediate vicinity of Lake may refer to the Yellowstone Boat Co. animals)

Supt. Annual 1908 "Wild herd: Reports from scouts and Report (1908) patrols state that signs of two buffalo calves were seen on Mirror Plateau and one cow and calf were seen in Pelican Valley during the season. Scout Wilson reported that he saw 10 buffalo at the mouth of Mist Creek on Lamar River on

April 1 3. On September 7 Scout McBride saw fresh tracks of 2 buffalo on Boundary Creek, near the western boundary, and on September 16 he saw 20 buffalo near the mush pots southwest of Pelican Cone in the valley of Pelican Creek. From these

reports it is evident that the remnant of

the original wild herd is gradually increasing in numbers." 138 Bison of Yellowstone National Park

Source Date Report

Skinner and Alcorn 1908 used a figure of 32 counted. (1942-51)

NOTE: On October 15, 1907, the Yellowstone Lake Boat Co. E. C. Waters corrals at Lake were torn down and the 8 buffalo within released. The Lake Station Record for the next two years and the scout diaries indicate that the various sightings of buffalo west of Lake Station, between Lake Station and Mud Geyser, and from Lake to Pelican Creek Bridge and east along the lakeshore for several miles were probably these animals. Reports of animals seen, or sign thereof, for these areas in 1908-09 are not included as part of this summary. Four or five buffalo were rounded up at Lake to be driven to headquarters in early December of 1909. North of Canyon, with average snow depths of 4 feet, the buffalo broke away. When last reported they had gone down into the Yellowstone Canyon to feed, apparently in the vicinity of Seven Mile Hole, where survival would be unlikely. Probably any left near Lake disappeared one by one without ever mingling with the wild herd. There was no indication that they ever joined the tame herd, of which very close track was kept at this time. The Boat Co. animals were of Goodnight plains bison stock, brought to the park in 1896, and kept in corrals (Timmons 1962).

Lake 15 & 16 Jan. 1909 patrol to Astringent Creek and White Station Record Lake, buffalo sign seen 23 March 1909 patrol to Astringent Creek cabin and White Lake, 3 buffalo seen 24 March 1909 sign at the Mushpot area on Pelican Creek

Scout Monthly 15 April 1909 4 buffalo near Yellowstone Lake, very Reports (1909) thin (these may have been part of Boat Co. animals, 6 were driven across the Pelican Bridge in Nov. 1908) 16 April 1909 Astringent Creek to Mist Creek and Lamar and to Willow Creek cabin, saw 3 buffalo near cabin 17 April 1909 patrolled north to Soda Butte, saw 2 buffalo

Supt. Annual April 1909 "Another small herd of 9 was seen near Report (1909) Pelican Creek in April." (this may be an error, representing the total of the above-

listed trip)

Scout Monthly mid-May 1909 "trying to corral 9 wild buffalo near

Reports (1909) Cache Cr. We captured 1 buffalo bull calf" Wild Bison 1903-19 139

Source Date Report

Supt. Annual May 1909 "A herd of 1 1 wild buffalo was seen on Reports (1909) Cache Creek May 19, at which time a bull calf was caught ..."

Anonymous 15 May 1909 lists 10 at the mouth of Cache Creek-2

File No. 21 & large bulls, 7 cows, 1 calf 22, 5/28/09

Supt. Annual July 1909 "Signs were also seen in the southwestern Report (1909) part of the park in July of this year."

Lake 23 Dec. 1909 Buffalo signs seen at Squaw Lake (Pelican Station Record area), 23 buffalo seen near Pelican Springs 13 Jan. 1910 buffalo signs 2 mi. west of Steamboat Sp. (Yellowstone Lake, north edge)

Scout Monthly February 1910 Soda Butte to Cache Creek and return, Reports (1910) saw 5 buffalo and signs of buffalo

Anonymous 23 Feb. 1910 29 buffalo seen on Pelican Creek (states File No. 21 & group known not to contain the Boat Co. 22, 3/2/10 buffalo)

Supt. Annual 1910 "A herd of 29 wild buffalo was seen in Report (1910) Pelican Valley on February 23, and a small herd of 5 was seen on Cache Creek on February 3. One old bull died during the winter in the vicinity of Yellowstone Lake, ..." (the one may have been from the Boat Co.)

Lake 9 March 1910 (Pelican Valley) "seen 20 of them" Station Record 16 March 1910 from Park Point (Yellowstone Lake) to Pelican Creek, 6 buffalo 17 March 1910 from Astringent Cabin to Lake, 21 buffalo 30 June 1910 Lake Station to 14 mile post, Sylvan Pass Rd., saw 7 buffalo

Lake 17 Feb. 1911 patrol to Pelican Cr., 20 buffalo Station Record

Anonymous Feb. ? part of wild herd sighted recently, sure of File No. 21 & 20, think 25 including some calves 22, 3/14/11 140 Bison of Yellowstone National Park

Source Date Report

Lake 2 March 1911 to Pelican Cabin, 25 buffalo Station Record Scout Monthly 28-30 April 1911 from Signal Point (on Yellowstone Lake) Reports (1911) north to Astringent Creek, saw 27 wild buffalo of which 2 were calves, traveled to Mist, Cold, and Willow Creek cabin N. to Lamar River, "sign of one wild buffalo'

NOTE: During June 1911,4 bison were rounded up on the Madison and brought to Mam- moth, in the mistaken belief that they were Yellowstone National Park animals. They were returned, including offspring, to their owners (Sherman) at Henry's Lake in June 1913 (Scout Reports and File No. 21 & 22).

Nowlin (1912) 1911 comments droppings indicated buffaloes had ranged near Saddle Mountain and on Mist Creek and the upper Lamar River; plenty of old signs along Pelican Creek, at White Lake on the head of Sour Cr., and near the heads of Deep Creek.

Thumb 10 August 1911 "patrolled to K. W. & De L. C. Reg. 82- Station Record 8 buffalo" (contrary to the Supt. Report, 1911, the 8 buffalo were probably seen at the Knotted Woods, southwest of Dryad Lake, rather than west of Thumb at DeLacy Creek)

Supt. Annual 1911 "The wild herd has been seen several Report (1911) times, usually in the Pelican Creek Valley. The largest number seen at any one time was 27. A patrol reported having seen 8 along the road, about 7 miles west of Thumb Station, on August 12." (error, see above)

Anonymous 13 July 1912 48 (inc. 10 calves) on Raven Creek

File No. 21 & 22 "Scouts McBride and Little . . . report 5/3/12 having actually seen and counted 48 7/19/12 animals. They are not together in a herd, but are considerably scattered, mostly on Pelican Creek, Upper Lamar River and tributaries." count included 10 this year's calves; one additional large bull on the Pitchstone for a total of 49 3

Wild Bison 1903-19 141

Source Date Report

Scout Monthly 6 July 1912 1 bull, signs of 1 more, Cache Cr. (may Reports (1912) have been from tame herd) 7 July 1912 sign of a small band, between Cache and Willow Creek 8 July 1912 sign of 6, Willow Cr. (seen by another scout) 9 July 1912 fresh sign, vicinity of Mist Cr.

lOJuly 1912 1 bull, signs of others, Mist Creek 11 July 1912 fresh sign, Mist to Raven Creek, (one seen by another scout) 12July 1912 "patrolled county" (Mirror Plateau), saw 38: 25 cows, 3 bulls, 10 spring calves, one seen between Snake River and Aster Creek 22July 1912 saw buffalo signs on Proposition Creek.

Nowlin (1912) 22-30 July 1912 trip made on Specimen Ridge and Mirror Plateau, upper Lamar River, Saddle Mt., Miller and Cache Creeks; fresh sign cow & calf Upper Pelican, tracks and droppings at head of Raven Creek, about 10 days old saw about 10 at the head of Timothy Cr., followed them to the headwaters of Clover Creek where they joined others, "all were feeding quietly in an open park."

total of 35 : 7 bulls inc. 2 large ones, 1 cows, 7 yearlings, 8 young calves, fresh sign of two bulls on Timothy Creek total counted for trip: 39

"However, the summer range is so ex-

tensive and difficult to traverse that it would require a great deal of time and

careful work to examine it thoroughly.

... I have never seen buffaloes on the range so wary and difficult to locate as the wild ones in the Yellowstone Park. ... As these buffalo winter around the

warm springs ... it seems reasonable to

me that if undisturbed, they ought to gradually increase."

Scout Monthly 20 Sept. 1912 2 buffalo seen between Cold Creek and Reports (1912) (approx.) the Lamar R. 27 Sept. 1912 25 wild buffalo, vicinity of Saddle Mt. 142 Bison of Yellowstone National Park

Source Date Report

Supt. Annual 1912 "A special effort was made during the Report (1912) month of July to determine as nearly as possible the exact number of buffalo in the wild herd in the park. Forty-nine animals, including 10 this year's calves,

were counted. . . . indicates that the herd

is thriving beyond expectation."

Anonymous winter added note: "Men on Lake Station claim File No. 21 & 22 1912-13 53 winter 1912-13 but not officially 8/2/12 reported."

Scout Monthly 28 Feb. 1913 saw 35 wild buffalo, trip from Yellowstone Reports (1913) Lake outlet to Pelican cabin

March (early) 1 bull, head of Mist Creek

Lake 17 March 1913 53 buffalo, patrol from Pelican cabin Station Record

Scout Monthly April 1 bull, trip from Cache to Willow Creek Reports (1913) on top of Miller Creek divide

Lake 30 May 1913 2 buffalo, patrol to Cub Creek Station Record

Scout Monthly 5 Sept. 1913 20 buffalo, trip from Cold Creek to Frost Reports (1913) Lake

Supt. Annual 1913 "No accurate count of the wild herd of Report (1913) buffalo was made, but scattering bands of them have been seen, and one party on patrol reports having seen 7 calves with a

herd at a distance. It is believed that there has been some increase."

Scout Monthly September sign seen, vicinity of Saddle Mt. Reports (1914)

Supt. Annual 1914 "No particular effort was made to make

Report (1914) an accurate count . . . but they have been seen in considerable numbers on several

occasions, . . . increasing slowly."

Stevenson 4 Dec. 1915 "went up Pelican Creek and Raven Creek (1915-16) to count Buffalo. 4 found on Pelican Cr.

27 on Raven Cr 31 in all about 5 large bulls 6 yearlings 4 calves and the rest cows and young bulls." Wild Bison 1903-19 143

Source Date Report

Supt. Annual 1915 "has not been practicable to get an ac- " Report (1915) curate count ...

NOTE: Superintendents' Annual Reports for a few more years indicate wild herd numbers, which will not be included in this summary, as they may represent the addition of some escaped tame-herd members. 144

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Appendix VI

KNOWN BISON MOVEMENTS TO AND BEYOND YELLOWSTONE NATIONAL PARK BOUNDARIES 1942-67

West Boundary South Boundary North Boundary East Boundary

Pop. No. Pop. No. Pop. No. Pop. No. Mary Mtn. No. out; location Mary Mtn. No. out; location Lamar No. out; location L'mr-Pln. No out; location

1942 Dec 742 A few; Gardiner

1942-43 late winter 742 1 30; down Yell R., most only about 10 days and returned

1943 Aug. 100 1 ; 1 Vt mi. S of S. Gate 800 est. 150; near Lake Abundance Sept. 3; vicinity S. Gate

1947 fall 500 31; Elk Cr.-Hellroaring area

1948 late winter 313 68; Gardiner-Jardine

1951 late Feb. 640 1 ; Young Ranch

March 1 ; Gallatin highway 380 est. 6; near line, inside

1955 Feb. 900 est. 3; Fall River Ridge

1956 Mar. 220 est. 8; Gardiner-Jardine

1957 Feb. 550 est. 6; Fall River Ridge

1959 Feb. 1 ; Bitch Cr.

1962 winter 135 est. 10; Eagle Cr.

1 963 winter 500 est. 34; Bechler Mdws. (in)

1 964 late winter 400 est. 1; Fall River Ridge 2; 7 mi. S. of

summer boundary 1 ; Mol Heron Cr.

fall 1 ; Fall River Ridge

1965 Jan. 400 est. 23; Bechler Mdws. (in)

1966 Mar. 400 est. 2; Fall River Ridge May 2-3; Cave Falls area 150 est. Some (bulb) July 1 ; Grassy Lake Upper Timber Cr. 2; West Entr. to Henry's Lake to Ennis Aug. 1;S. Gate

1967 late winter 200 est 2; 9 calved, 1 cJPorcu- pine-Warm River cow + calf Porcu- pine

Often-summer

Every year-summer A few; Upper Hellroaring and Slough drainages

years pers. comm.) there are few wild bison in that area from ranched herds of some NOTE: Refuge Manager Vivion, Red Rock Lakes National Wildlife Refuge, states (1968 a ago. Occasional west side reports may not actually be Yellowstone bison. 150

Appendix VII

OCCURRENCE OF GRASSES AND GRASSLIKE PLANTS IN BISON USE AREAS.

Location

a Type of Site Species F HV L P ULb

Pond and creek Sedge (Carex spp.

edges, wet C. aqua ti Us) bottomlands Beaked Sedge Nebraska Sedge Woolly Sedge Western Bulrush

Swales, wet Sedge (Carex spp. C. acuta C. aperta C. aquatilis C. platylepsis

C. ray no Ids ii C. xerantica) Beaked Sedge Silvertop Sedge Smallwing Sedge Woolly Sedge Spike-sedge Horsetail Wire Rush Grass species Meadow Barley Sweetgrass Timothy Tufted Hairgrass

Moist meadows Sedge (Carex spp. C. acuta C. athrostachya C. platylepsis C. raynoldsii) Smallwing Sedge Valley Sedge Woolly Sedge Horsetail Long-styled Rush Wire Rush Grass species Alpine Foxtail Bluegrass Canby Bluegrass 1

Grasses and Grasslike Plants 1 5

Location

a b Type of Site Species F HV L P UL

Cusick Bluegrass X Kentucky Bluegrass X Giant Wild-rye X Sweetgrass X X Timothy X Tufted Hairgrass XX XX

Moist upland sites Grass species XX X Bluegrass XX XX Giant Wild-rye X Idaho Fescue XX XX Meadow Barley X Mountain Brome XX X Columbia Needlegrass X Richardson Needlegrass X Timber Oatgrass X Timothy X

Drier upland sites Sedge (Carex xerantica) X X Smallwing Sedge X Grass species X X Bluegrass XX X Canby Bluegrass X Cusick Bluegrass X Kentucky Bluegrass X Sandberg Bluegrass X Idaho Fescue XX XX Junegrass XX X Needle-and-Thread X Needlegrass X X Columbia Needlegrass X Richardson Needlegrass X Tufted Hairgrass X Wheatgrass X X Bluestem Wheatgrass X Bluebunch Wheatgrass X Slender Wheatgrass X Thickspike Wheatgrass X

Mountain herbland Sedge {Carex aperta X C. raynoldsii X C. xerantica) X Ovalhead Sedge X Smallwing Sedge X Slender Rush X Wire Rush X 152 Bison of Yellowstone National Park

Location

Type of Site Species F HV La P ULb

Bluegrass X Alpine Bluegrass X Canby Bluegrass X Idaho Fescue X Meadow Barley X Mountain Brome X Needlegrass X Purple Onion Grass X Timothy X Alpine Timothy X Slender Wheatgrass X Tufted Hairgrass X

Drier mountain sites Long-styled Rush X Bluegrass X Idaho Fescue X Junegrass X Timber Oatgrass X

Subalpine meadows Sedge (Carex nova X C. platylepsis X C. raynoldsii) X Hepburn Sedge X Smallwing Sedge X Bluegrass X Alpine Bluegrass X Timberline Bluegrass X Idaho Fescue X Meadow Barley X Alpine Timothy X Tufted Hairgrass X

F = Firehole HV = Hayden Valley L = Lamar P = Pelican UL = Upper Lamar a Data is more complete for Lamar. b All wet sites are at higher elevations. References

1883. Game Allee, W. C, O. Park, A. E. Emerson, T. Bozeman Avant-Courier. Park. 1 1 Jan- Park, and K. P. Schmidt. 1949. Principles features of the Yellowstone of animal ecology. W. B. Saunders Co., uary. Philadelphia, Pa. 837 p. 1883. Park pencillings. 22 Febru- ANON. 1909-11. Reports. In: File No. 21 & ary. 22. Buffalo. Yell. Natl. Park Archives. Burger, John F. 1967a. Diptera: Rhagioni- 1912-13. Reports. In: File No. 21 8c dae. Effect of abundance on wildlife. 22. Buffalo. Yell. Natl. Park Archives. Rept. to the Natl. Park Serv. Yell. Natl. Bailey, Vernon. 1930. Animal life of Yel- Park Library. Typed. 2 p. lowstone National Park. Charles E. . 1967b. Letter to Sup't. McLaughlin, Thomas, Springfield, 111. 241 p. Yell. Natl. Park, 13 March 1967. Yell. Bailey, Virginia L., and N.E. Bailey. 1949. Natl. Park Library. Typed. 4 p. Woody plants of the western national Burgess. F. 1898-99. Scout diary. Yell. parks. University Press, Notre Dame, Ind. Natl. Park Archives. 274 p. Cahalane, Victor H. 1944. Restoration of P. Barlow, J. W., and D. Heap. 1872. Re- wild bison. Trans. N. Am. Wildl. Conf. port of a reconnaissance of the basin of 9:135-143. the upper Yellowstone in 1871. U. S. Choquette, Laurent P. E., Guy Cousi- Gov't. Printing Office, Washington, D.C. J. NEAU.and Eric Broughton.1966. Pathol- 43 p. ogy. Can. Wildl. Ser. Annual Report, p. Barmore. William 1968. Bison and bru- J. 75-80. cellosis in Yellowstone National Park: a Christman. Gene N. 1971. The mountain problem analysis. Yell. Natl. Park. Typed bison. The American West. 8(3):44-47. report. 73 p. Bergstrom. R. C. 1964. Competition be- Cole. Glen. 1969. The elk of Grand Teton tween elk and phytophagous insects for and southern Yellowstone National Parks. Research Report N-l. food in the Lamar Valley, Yellowstone GRTE— National Park. Ph.D. Thesis. Univ. of Mimeo. 192 p. Conner. A. H., and Robert Cornell. Wyoming, Laramie. 107 jJ- 1958. Brucellosis in bison, elk, and moose Blagkmore, WM. (Lord): 1872. Diary- in Elk Island National Park, Alberta, fourth visit to the United States. (Tran- Canada. Can. Comp. Med., Vet. Sci. scription, Western Range Cattle Industry J. 22:9-20. Study. State Museum, Denver, Colo.) Cook, Charles W., David E. Folsom. and Yell. Natl. Park Library. Photocopy. Boone and Crockett Club. 1964. Records William Peterson. 1869. An exploration the Yellowstone Riv- of North American big game. Holt, Rine- of the headwaters of er in the year 1869. In: Haines, Aubrey hart & Winston, New York. 398 p. Yel- Booth, W. E. 1950. Flora of Montana. Part ed. 1965. The valley of the upper lowstone. University of Oklahoma Press, I. Conifers and monocots. The Research Foundation at Montana State College. Norman. Delacy, Walter W. 1876. A trip up the Bozeman. 232 p. south Snake River in 1863, p. 113-143. Booth, W. E., and J. C. Wright. 1959. In: Contributions to the Historical Society Flora of Montana. Part II. Dicotyledons. 1966. The Research Foundation at Mon- of Montana. V. I. Rocky Mountain Pub- lishing Co., Helena. tana State Univ., Bozeman. 305 p.

153 154 Bison of Yellowstone National Park

DOANE, G. C. 1875. The report of Lieut. per Missouri, to the Yellowstone National

Gustavus C. Doane upon the so-called Park. U. S. Gov't. Printing Office, Wash- Yellowstone Expedition of 1870 to the ington, D. C. Secretary of War. Appendix M. In: Hague, Arnold. 1893. The Yellowstone

Cramton, Louis C. 1932. Early history of Park as a game reservation, p. 240-270.

Yellowstone National Park and its rela- In: American big game hunting, the book

tion to national park policies. U. S. Gov't of the Boone & Crockett Club. Forest 8c Printing Office, Washington, D.C. Stream Publishing Co., New York. 1876. Expedition of 1876-1877. 1899. Geology of Yellowstone Na-

Yell. Natl. Park Library. Typed. 44 p. tional Park. U. S. Geo. Survey. Mono- Dunraven, Earl Of. 1876. The great di- graph 32, Part 2. U. S. Gov't. Printing

vide. Chatto & Windus, London, Eng- Office, Washington, D.C. 893 p. land. 382 p. Haines, Aubrey, ed. 1955. Osborne Rus- Etkin.William. 1964. Types of social or- sell's journal of a trapper. Oregon Histor-

ganization in birds and mammals, p. 256- ical Society, Portland. 179 p.

297. In: Etkin, William, ed. 1964. Social . 1963. History of Yellowstone Na-

behavior and organization among verte- tional Park, p. 84-136. In: A manual of brates. University of Chicago Press. Chi- general information on Yellowstone Na-

cago, 111. tional Park. Yell. Natl. Park. Mimeo. FRICK, E. 1951. Halloran, A. F. 1968. Bison (Bovidae) J. Parasitism in bison. J. Am. Vet. Med. Assoc. 119:386-387. productivity on the Wichita Mountains FRYXELL, Fritiof M. 1926. A new high alti- Wildlife Refuge, Oklahoma. Southwest tude limit for the Nat. American bison. J. 13:23-26. Mammal. 7:102-109. Henderson, A. Bart. 1870. Narrative of a Fuller, W. A. 1959. The horns and teeth as prospecting expedition to the East Fork

indicators of in bison. Clark's Yellowstone. . .1870. age J. Wildl. Man- and Fork of age. 23:342-344. (Original in Coe Collection, Yale Univ. 1960. Behavior and social organiza- Library.) Yell. Natl. Park Library. Typed tion of the wild bison of Wood Buffalo transcript. National Park, Canada. Arctic. 13: 3-19. Hofer. T. E. 1927. Letter to LeRoy Hill. 5 1961. The ecology and manage- February. Yell. Natl. Park Archives. ment of the American bison. Extrait de la Holmes. W. H. 1878. Exploration of the Terre et la Vie. 2-1961:286-304. Yellowstone National Park by the U. S. 1962. The biology and manage- Geological and Geographical Survey of ment of the Bison of Wood Buffalo Na- the Territories, 1878. Yell. Natl. Park tional Park. Can. Wildl. Serv. Wildl. Man- Library. Typed transcript. 43 p. age. Bull. Ser. l,No. 16. 52 p. Garretson, Martin S. 1938. The Ameri- Holt, Peter. 1899-1901. Scout diary. Yell. can bison. New York Zool. Soc. 254 p. Natl. Park Archives. Gilman, N. L., and John L. McAuliff. Hough. Emerson. 1894. Forest and

1956. Brucellosis, p. 538-556. In: Finch- Stream's Yellowstone Park expedition of er, M. G., ed. 1956. Diseases of cattle. 1894. Yell. Natl. Park Library. Newspa- American Veterinary Publishers, Inc., per account.

Evanston, 111. Houston, Douglas B. 1968. The Shiras Yellow- Grimm, Rudolf L. 1939. Northern moose in Jackson Hole, Wyoming. Grand studies. Wildl. Man- stone winter range J. Teton Natural History Assoc. Grand Te-

age. 3:295-306. ton Natl. Park. 110 p.

Grinnell, Geo. Bird. 1876. Zoological Jones, William A. 1875. Report upon the report, p. 66-89. In: Ludlow, William. reconnaissance of Northwestern Wyo- 1876. Report on a reconnaissance from ming including Yellowstone National Carroll, Montana Territory, on the Up- Park, made in the summer of 1873. U. S. References 155

Gov't. Printing Office, Washington, D.C. Oldf.meyer. John L. 1966. Winter ecology

331 p. of bighorn sheep in Yellowstone National Kittams, Walter H. 1947-58. Northern Park. M. S. Thesis. Colorado State Univ., winter range studies. 2 Vol. Yell. Natl. Fort Collins. 107 p.

Park Library. Typed. Park, Ed. 1969. The world of the bison. J. B. LippincottCo., Philadelphia. Pa. 161 p. . 1949. Preliminary report on Hay- Patten, D. T. 1963. Vegetational pattern den Valley bison range. Yell. Natl. Park in relation to environments in the Madi- Library . Typed. 8 p. son Range, Montana. Ecol. Monogr. Lake Station. 1898-1911. Station re- 33:375-406. cord. Yell. Natl. Park Archives. Pattie, Donald L., and Nicolaas A. M. 1911-18. Station record. Yell. Natl. Verbeek. 1967. Alpine mammals of the Park Archives. Mountains. Northwest Sci. Le Hardy, Paul. 1873. Autobiography of Beartooth 41:110-117. Paul Le Hardy, p. 95-104. (Typescript Pierrepont, Edward, 1884. Fifth avenue to copied from handwritten 247 p. auto- Sons, New York, biography.) Yell. Natl. Park Library. Alaska. G. P. Putnam Livingston Enterprise. 1885. News arti- 329 p. Mrs. Lena. 1962. Notes from an cle. Mar. 7:3; Dec. 12:1; Dec. 19:3. Potter, Locker, Betty. 1953. Parasites of bison in interview. Yell. Natl. Park Archives. Tape Parasitol. 39:396- recording. northwestern U.S.A. J. 397. Quortrlp, Erling R. 1945. A report on MacArthur, Robert, and Joseph Con- brucellosis investigations, Yellowstone nell. 1966. The biology of populations. National Park. Dec. 1-20, 1944. Yell. Natl. John Wiley & Sons, New York. 200 p. Park Library. Mimeo. 27 p. McHUGH, Tom. 1958. Social behavior of Raymond, Rossiter W. 1880. Camp and the American Buffalo (Bison bison bison). cabin: sketches of life and travel in the west. Fords, Zoologica. 43, Part 1.31 March 1958. 40 p. Howard & Hulbert, New York. 242 McDougall. W. B., and Herma A. Bag- p. Raynolds, W. F. 1867. Report of Brevet GLEY. 1956. Plants of Yellowstone Nation- Colonel W. F. Raynolds, U. S. A., Corps al Park. Yell. Library and Museum, Assoc. of Engineers, on the exploration of the Yell. Natl. Park, Wyo. 186 p. Yellowstone and Missouri Rivers in 1859- Marble, Charles. 1932. Fifty years in 1860. 40th Congr., 1st Sess. Senate Ex. and around Yellowstone National Park Doc. No. 77. U. S. Gov't. Printing Office, and miscellaneous notes. Yell. Natl. Park Washington, D. C. 174 p. Library. Typed. 36 p. Robinette. W. Leslie,' Jay S. Gashwiler, Meagher, M. 1 966. Lungworm (Dictyocau- Dale A. Jones, and Harold S. Crane lus sp.) in bison of Yellowstone National 1955. Fertility of mule deer in Utah. /. Park. Yell. Natl. Park Library. Typed. 8 p. Wild^ Manage. 19:115-136. Mech, L. David. 1966. The wolves of Isle Roe, Frank Gilbert. 1951. The North Royale. Fauna of the Natl. Parks of the American buffalo. University of Toronto U.S. U.S. Gov't Printing Office, Washing- Press, Canada. 957 p. ton, D.C. 210 p. Rush. W. M. 1932a. Bang's disease in Yel- Morrison, James. 1897-98. Scout diaries. lowstone National Park buffalo and elk 2 Vol. Yell. Natl. Park Archives. herds. /. Mammal. 13:371-372. Mlrri, Ernest. 1968. Interview of 5 May . 1932b. Northern Yellowstone elk 1968 by Natl. Park Service personnel. study. Mont. Fish Game Comm., Helena. Yell. Natl. Park Archives. Tape recording. 131 p. NOWLIN, D. C. 1912. Report on wild buffalo Scouts. 1908-14. Monthly reports. Yell. and elk, Yellowstone Park. July 22-30. Natl. Park Archives. Typed. 5 In: File No. p. 21 & 22. Buffalo. Skinner, Curtis K. 1941. Special report on 1909-1 1 inc. Yell. Natl. Park Archives. Yellowstone National Park bison. Yell. 1 56 Bison of Yellowstone National Park

Natl. Park Bio. Files. 715-03. Buffalo Thumb Station. 1898-1916. Station rec- (General). Typed. ord. Yell. Natl. Park Archives. Timmons, William. 1962. Twilight on the Skinner, Curtis K., and Wayne B. Alcorn. range. University of Texas Press, Austin. 1942-51. History of the bison in Yellow- 223 p. stone Park. Yell. Natl. Park Library. Tunnicliff, E. A., and H. Marsh 1935. Typed report. Bang's disease in bison and elk in the Yel-

Skinner, Morris F. 1965. Letter to Dr. J. D. lowstone National Park and on the Na-

Love, U.S.G.S. 19 Nov. Yell. Natl. Park tional Bison Range. J. Am. Vet. Med. Museum Files. Assoc. 86:745-752. Kaisen. Skinner, Morris F., and Ove C. U. S. Dep. Agric. SoilConserv. Serv. 1919- 1947. The fossil Bison of Alaska and pre- 67. Summary of snow survey measure- liminary revision of the genus. Bull. Am. ments. Wyoming, Casper. 152 p. Mus. Nat. His. 89: 127-256. U.S. Dep. Commer. Weather Bureau. 1897. Monthly re- Snake River Station. 1930-59. Climatological summary for Yel- Archives. port, August. Yell. Natl. Park lowstone National Park. Climatography Butte Station. 1898. Station Soda of the U.S. No. 20-48. 2 p. Archives. record. Yell. Natl. Park Whittaker, George. 1897-99. Scout dia- Soil Conservation Service. 1963. Site ries. 4 Vol. Yell. Natl. Park Archives. condition survey, northern Yellowstone. Woolf, Alan. 1968. Summer ecology of Yell. Natl. Park Bio. Files. bighorn sheep in Yellowstone National

. 1964. Site condition survey, Hay- Park. M. S. Thesis. Colorado State Univ.,

den-Pelican Creek. Yell. Natl. Park Bio. Fort Collins. 112 p. Files. Yount, Harry. 1880. Report of game- 1915-16. diary. Stevenson, Donald. Scout keeper, p. 50. In: Superintendents of the Yell. Natl. Park Archives. Yellowstone National Park. 1880. Annual Yellowstone Na- Superintendents of the report. Yell. Natl. Park Library. tional Park. 1877-1915. Annual reports. . 1881. Report of gamekeeper, p. 62- Yell. Natl. Park Library. 63. In: Superintendents of the Yellow- 1903-21. Journal. Yell. Natl. Park stone National Park. 1881. Annual re- Archives. port. Yell. Natl. Park Library. Index

Page Page Accidents 74 Brown, Larry 66 Anthrax 70 Browse species 93,94 Barmore, William 109 Brucellosis infection Bechler Meadows 3,5 Examination for 2 Summer range 23 Control 71 Wintering 33,88 Effect on productivity 71 Winterkill 74 First reported 70 Biotic disclimaxes 108 Rate of 54 Bison behavior Buffalo Ranch 39,67,71 Breeding activity 47,76,77 Buffalo trails 25 In snowstorms 47 Bulls "Tending bonds" 51 Distribution 36,37 Winter movement 73 Free-ranging 29,31 Bison bison athabascae Rhoads 1,13 Groups 46,84,98 Skulls 16,17 Horning of trees 104

Bison bison Linnaeus 1 Insects 83 Bison characteristics 38-49 Movements 78,85 Color 38 Physical characteristics 38 Hair 38 Population ratio 60 Horns 38 Reductions 29 Longevity 46 Sexual maturity 51 Sight 47 Show herd 29 Smell 47 Solitary 46

Speed 47 47,49,£$1 ,84,85,89,98,99 Weight 38,39 Thermal areas 105 Bison occidentalis 13 Wallows 104,105 Bison population Weight 39 Breeding activity 47,76,77 Winter ranges 81,99,100 Composition 27,29 Wintering apart 37,96,99 Distribution 13,32,34,35,37 Calves Estimates 67 Calving 75,76 Group structure 46,90 Coat color changes 38 Interbreeding 85,88,89 Dominance hierarchy 111 Intermingling 29,88 Fetal size range 75 Isolation 89 Mortality 62,64 Movements 36,73 Numbers 60,63 see also Migratory movements Nursing 51,54 Origin 1,13,14,26 Sex ratio 58 Reproduction 50-57 Survival rates 51,54,111 see also Reproduction entries Wild herd 26,27 Blackflies (Simulium venustum) 69 Chapman, W. S. 31 Blacktrail Dee Creek 104 Childs, Frank 13

157 1

158 Bison of Yellowstone National Park

Page Page Climate 8 Thermal sites 97,108 a 13 Effect of wind and cold 56 Use of areas 96-103 Seasons 9 Forbs in forage 92-94 Colter, John 12 Goodnight herd 26 Cows Grass species 91-95 Abortions 54,70 Great Plains bison 14 Brucellosis 70 Grizzly (Ursus horribilis) 72 Calving 75,76 Hague, Arnold 15 Low reproductive rates 56 Haines, Aubrey 13 Pregnancy rates 54 Hayden Valley 3 Sexual maturity 50 Area 5 Winter range preference 89,90 Breeding activity 77 Crystal trap 2,58 Bulls wintering 36 Dominance hierarchy 1 1 Calving 76 Effects on habitat 103-109 Counts 33 Plant cover 106 Grass species 94 Trails and wallows 104,105 Horning, rubbing 103,104 Trampling 105,107 Insects 83 Trees and treeline 103,1041 /AO 1 f\ A Interbreeding 86 Upland sites 108 Migratory patterns 78,84 Elk (Cervus canadiensis) 47 Summer range 23,81,89 104,107,108 Thermal areas 100,102 ' 1 , 1 1 X " 1 Elk1711, IslandI National f->Park 69 Vegetation 10 Face fly (Musca autumnalis) 70 Wallows 105,106 Fenced herd 27-30 Winter range 23,33,96 Composition 28,30 Hemorrhagic septicemia 70 Discontinued 32 Herd reductions 1 Intermingling 29 2,29,32,52,66,67,72,88 Fetal sex ratio 55,56 Methods used 2 Firehole region 2,3 Hornfly (Haematobia irritans) 70 Area 5 Horse and deer flies (Tabinidae) 69 Calving 76 Hot springs or fumaroles 102 Effects of bison 106 Insects, biting 69,70 Interbreeding 86 Summer movement 82,83,97 Mary Mountain area 32 Lacey Act 12,17 Migratory pattern 78,84 Lamar region 1,3,12 Thermal areas 100,102 Area 4

1 o Vegetation 1U Brucellosis 54,70 Food habits 2,90,93 Bulls 60 Foraging areas 96-98 Calving 75 Composition data 94 Increase 67 Effect on plant cover 106-109 Management practices 26,32 Forbs and browse 94 Movement 82 Forested sites 97 Poaching 17 Snow depth 73 Reduction 32,65,66 Index 159

Page Page Summer range 23 Trails Trapping 58 Vegetation 10 Vegetation 10 wild nera 9A no Winter range 23 Mixed herd groups CO r» 11 A 1 31,33,36,89 Bulls 4 / Lungworm (Dictocaulus sp.) 69 Can numbers OU,Oo no Q o 9 A Madison Plateau 3,5,33 Distribution Elk 194 Group size 40A& Summer range 23,65 Group structure 90 Management objectives 71 Migratory pattern 11 *7tt QO practices Management 1,2,12,26 Population shifts o / ,oo

1 1 Aerial counts 32,36,60 Survival factors 1 lo Buffalo ranch 67 Thermal areas QQ 1 f\(\ 1 no Change to natural preservation 32 Winter movements HA ft Ft ftQ on Cows and calves removed 52,53 Moose (Aires alces) DO Hay-baiting 31,67 Mortality by helicopter 1A Herding 33 Accidents 1 4 Population counts 32 nulls UJ Reductions 29,32,52,67 Calves A9 Azl Roundup 29 Disease-caused in/0 Tagging 2 Natural a p. p.i Mary Mountain herd 31,32 Predation Age classes 60,64 Subadults 04,ClA ia/4 Breeding 76 winterKiii 1%1 O, 1A1 4 Increase 65,68 Mosquitoes (Aedes sp.) Interbreeding 86 Mountain bison 114A

Reduction 66 Characteristics 1 4 1 ^

1 1 1 Q Semidomestication 68 Distribution 1 /, lo Sex ratio 60 History 15-17 Wintering 33,89,90 Increase 29 Migratory movements 77,97 Migrations 15 Beyond park boundaries 85 Numbers (1902) 17 Biting insects 82 Skulls 17 Patterns 90,97 Subspecies 89 Spring and fall 78,84 Mountain buffalo history 15-17 Summer 81,82,84 Mule deer (Odocoileus hemionus) 56 Winter 84 Murphy, R 85 Mirror Plateau 3,4 Muscidae 69,70 Area 4 Mush pots- Mudkettles 97 Breeding activity 76 National Bison Range 69 Fossil cranium 13 Conjunctivitis 70 Migratory pattern 78 Nez Perce trap 2,33,58 Rubbing of trees 103 Brucellosis 70 Skull 17 Helicopter drive 84,89 Summer range 23,31,36 Norris 15,17,25 1J

160 Bison of Yellowstone National Park

Page Page 9A Pablo-Allard herd Pregnancy rates 51,54,1 1 Parasites oy,AO. 7fl/u Sex ratios 55,56 Pelican region 3 Sexual maturity r;n f;a

Area 4 Research 1 o Brucellosis o4, /U Methods used I on Calving 75 Rocky Mountains oy Herd fluctuation 66,67 Rubbing of trees 103,104 O (\(\ C\1 Maximum population 113 Rumen samples

1 A Migratory pattern 82 Russell, Osborne 14

1 1 ^ Reductions 110 Sagebrush-grassland 1 1 Separation 88 Seasons yQ Vegetation 10,96 Sedge 90-93 Wild herd 26 94,95 Winter range 23,33,36,96,102,108 Thermal influence 102 Pierson, Dave 36 Winter forage 47,54,71,72,78 okuiis 16 17, 39 o Pitchstone Plateau 3,5 Slaughter operations 4 Summer range 23,65 Snipe flies (Rhagionidae) fiQ

Plains bison 1 Snow OA 97 Subspecies Trapping Wild herd 26,27 Winter foraging 1 o f; a Poaching 17,1 10 Soils Ponumpta Hot Springs 36,99 Erosion 107 Population regulation 110-113 Qtcihl^ flv {^tnmnxvs calcitrans) 70 Counting practices 32,33 Stradley, Jim 32, 33, 36, 66, 85, 102, 113 Natural regulation 110,111 Subspecies 13,14,26,27 Neckbands 2,36 Rocky Mountains 89 Numbers (1902) 17 Summer ranges 31,36,65 Numbers (1964) 33,108 Historic 23 Reductions 2 Survival factors 113 29,50,60,65,71,110 Symphoromyia 69,83 Slaughter operations 2 69 Tape worm ( Moniezia benedini) Tagging 2 Thermal areas 9,96-98 Population structure 8,58-60,89 Survival factor 113 Age classes 58-60,64 Thermal influence 102,103 Fluctuations 67 Trampling 105 Interbreeding 85,86 Use of 99,100,108 Sex ratio 58,60 Wintering sites 97,98 Trends 68 Trapping 58 Wild strain 29 Population shifts 88 Predation 72 Sex and age structure 59 Quortrup, E.R. 75 Reproduction 50-57 Tuberculosis 70 Calving 75,76 U.S. Forest Service 10 Eff ect of winter 56 Upland sites 108 11 1

Index 161

Page Page

Upper Lamar region 3,4 \A/intf»rlf ill 73,74 Area 4 Wire rush 94

Summer ranges 23,3 1 ,36 Wolves (Cams lupus) 72 Trails 105 Wood Buffalo National Park bison 51 70 7 Vegetation 9- 1 Diseases 69 Plant species 1 Parasites Visitors' best viewing 48 IXCIJI k)UL UCll VC laltJ 56 60 Wallows 104,105 Sex ratio climate 56 Wild herd 1,12,26,68 Winter 72 Present composition 27 Wolves Yearlings 54 Reproduction rate 5 Moose 56 Wild strain estimate 29 Mortality 64,111 Wildlife protection 12 TraDDinET 58 Wilson, Richard 14 Yellowstone National Park 3-12 Wind, effect of 56 Bison range 3 Winter ranges Climate 8 Effect on plant cover 106,108 Geologic history 3 Factors of suitability 112,113 History 10 Habitual 89,90 Indians 10 Sedges 94,96 Nine regions 3-5 Thermal sites 97,98 Seasons 9 U. S. Department of the Interior

U. S. GOVERNMENT - PRINTING OFFICE ; 1973 O 521-650