I (Ie De/;,;;I; D·· 3g>' I \N ITHE :.Tnf,';AGt:: I GRIZZLIES OF !MOUNT McKINLEY I Adolph Murie I I I I I •I I I II I ,I I' I' Ii I I I •I I I Ii I I I I r THE GRIZZLIES OF I MOUNT McKINLEY I I I I I •I I PlEASE RETURN TO: TECHNICAL INfORMATION CENTER I f1r,}lVER SiRV~r.r Gs:t.!TER ON ;j1,l1uNAl PM~ :../,,;ICE I -------- --- For sale h~' the Super!u!p!u]eut of Documents, U.S. Goyernment Printing Office I Washing-ton. D.C. 20402 I I '1I I I I I I I I .1I Adolph Murie on Muldrow Glacier, 1939. I I I I , II I I' I I I THE GRIZZLIES I OF r MOUNT McKINLEY I ,I Adolph Murie I ,I I. I Scientific Monograph Series No. 14 'It I I I U.S. Department of the Interior National Park Service Washington, D.C. I 1981 I I I As the Nation's principal conservation agency, the Department of the,I Interior has responsibility for most ofour nationally owned public lands and natural resources. This includes fostering the wisest use ofour land and water resources, protecting our fish and wildlife, preserving the environmental and cultural values of our national parks and historical places, and providing for the enjoyment of life through outdoor recre- I ation. The Department assesses our energy and mineral resources and works to assure that their development is in the best interests of all our people. The Department also has a major responsibility for American Indian reservation communities and for people who live in Island Ter- I ritories under U.S. administration. I I I I Library ofCongress Cataloging in Publication Data 4 Murie, Adolph, 1899- The grizzlies of Mount McKinley. I (Scientific monograph series; no. 14) S upt. of Docs. no.: I 29.80: 14 Bibliography: p. I Includes index. I. Grizzly bear-Behavior. 2. Mammals­ Behavior. 3. Mammals-Alaska-Mount McKinley National Park. 4. Mount McKinley National Park. I l. Title. II. Series: United States. National Park Service. Scientific monograph series; no. 14. QL737.C27M87 599.74'446 80-607120 I I I I I , Contents I PREFACE Xl ACKNOWLEDGMENTS xiii I SUMMARY xv Chapter I INTRODUCTION I Chapter 2 STUDY BACKGROUND 4 Classification and Characteristics 4 Habitat II I Numbers and Density 14 Age Determination ofCubs 17 Some Family Statistics 20 I Tracks and Trails 23 Chapter 3 I RANGE AND MOVEMENT 33 Home Range 33 Joint Occupation of Range 61 Movements ofTransported Bears 76 • Chapter4 THEFAMILY 79 I Mating 79 Nursing 92 Aspects of Famity Life 103 Retirement to Cliffs III I Mother-Cub Separation 117 Cub Companionship After Separation From Mother 126 I Chapter 5 SUBSISTENCE 133 Hibernation 133 I Food Habits 135 Carrion and Caching 159 I v I I ,I Chapter 6 I I GRIZZLIES AND UNGULATES 171 Grizzly-Caribou Relationships 171 Grizzly-M oose Relationships 186 I I Grizzly-Dall Sheep Relationships 198 Chapter 7 GRIZZLIES AND RODENTS 209 I Grizzly-Ground Squirrel Relationships 209 G rizzly-M armot Relationships 216 Grizzly-Mouse Relationships 216 I Grizzly-Beaver Relationships 218 Grizzly-Porcupine Relationships 218 I Chapter 8 GRIZZLIES AND CARNIVORES 223 Grizzly-Wolf Relationships 223 Grizzly-Wolverine Relationships 226 I Grizzly-Fox Relationships 227 Chapter9 GRIZZLIES AND BIRDS/ INSECTS 231 4 Grizzly-Golden Eagle Relationships 231 Grizzly-Magpie Relationships 232 Grizzly-Raven Relationships 234 I Grizzly-Insect Relationships 234 Chapter 10 I GRIZZLIES AND MAN 235 Chapter II I KEEPING GRIZZLIES WILD 239 REFERENCES 243 INDEX 245 I VI II I I I I , Figures I Frontispiece: Adolph Murie on Muldrow Glacier, 1939. Denali (Mt. McKinley) stands above the grizzly's domain. xviii I 2 The shoulder hump and dished facial profile easily distin- guish grizzlies from black bears in the field. 5 I 3,4 Forefeet and hind feet of grizzlies are clearly distinguishable. 6,7 5 Here a glacial stream has shifted its channel and is washing away an old vegetated river bar. 12 I 6 Here the glacial stream is washing away a wooded flat. 13 7 A female grizzly with two spring cubs on Sable Pass. 16 I 8 Mother with spring cub. 18 9 Some spring cubs have distinct white patches on the sides of the neck. 18 I 10 Mother with yearling in spring of 1964. 19 II Mother with 2-year-old cubs feeding on first green grass ~ blades. 20 12 Bear trail descending steep snow slope. 25 13 A bear tree, used for rubbing. 29 I 14 Mother grizzly and yearling crossmg a late spring snow patch. 33 I 15 Map of the study area, Mt. McKinley National Park. 42 16 Approximate home ranges for two females recognized for periods of4 years. 44 I 17 The dark brown female and her cub received a scare from photographers. 47 I 18 Approximate observed home range of a blond female with one spring cub in 1964 seen the following 3 years. 48 I VB I 19 A female and her spring cub watch intently as a lone bear I passes nearby. 20 The crippled male patiently following his female mate. 21 A mother nursing her spring cub, in the typical nursing posture for grizzlies. 22,23 This female used a telephone pole for backscratching. Minutes later her tiny spring cub rubbed its back on the pole. 106 24 During the breeding season females with cubs often spend the night in cliffs. 112 I 25 Mother with spring cub, followed by a 3-year-old cub. 124 26 The old cub watches mother, not daring to approach. 125 I 27 The older cub, chased by the female, had approached close to her and is here leaving in a hurry. 125 28 Twins, about 4 years old, still companionable after leaving I their mother. 128 29 A lone bear seeking food after an early September snowfall. 132 I 30 Dens used by bears for overwintering appear to be located throughout the summer range in the park. 134 31 Grizzlies expose succulent roots by loosening chunks of sad I with their forepaws. 138 32 Here grizzlies had been digging for the roots of peavine. 139 I 33 Winter deposits of overflow ice give some bars a respite from bear-digging, since they do not melt until summer. 140. 34 The fleshy roots ofpeavine are a principal food ofbears in the spring. 148 I 35 The juicy-stemmed A rctagrostis is the grass species eaten most frequently by grizzlies. 149 II 36 Boykinia. a showy saxifrage, is a major food item in favored grazing areas on Sable Pass. 150 I 37 One of the attractions for bears on Sable Pass is the sourdock (Rumex arcticus). 151 38 Some bears spend hours grazing on Oxytropis viscida. 152 I 39 Blueberries are a major bear food In late summer. 153 I Vllt I I I 40,41 Additional information on food habits can be gained by examining bear scats. 156,157 I 42 This carcass of a caribou bull was mostly covered with sod and vegetation by a grizzly. 166 43 Robust caribou such as these almost never supplement the r grizzly diet. 172 44 Migrating caribou. 172 45 The flats south ofPolychrome Pass where bears seek caribou I calves in some years. 180 46 Caribou seeking snow to minimize the attack of botflies and I nose flies. 187 47 Mother moose followed by a very young calf. 187 48 An old bull moose at the beginning of the rut. 194 I 49 A cow moose may put a bear to flight, especially if the bear is not a large adult. 196 50 Dall sheep, not much worried about bears. 199 I 51 A band of Dall sheep, in migration across a valley. 201 52 Not long after this picture was taken a bear captured a strag- I gling lamb. 204 53 Bears often are seen excavating ground squirrels. 210 54 A young bear looking for a ground squirrel. 212 I 55 Hoary marmots seldom are captured or excavated from their burrows. 217 56 As a rule the bears seem to keep at a safe distance from porcupines. 219 57 Bears often benefit from animals killed by wolves. 222 • 58 I have observed numerous fox dens located in choice bear I country but rarely have seen any disturbance of them by bears. 228 59 Both golden eagles and grizzlies hunt ground squirrels and I are attracted to carrion. 233 60 Photographers sometimes experience unsettling moments. 236 61 Napier Shelton standing beside a spruce tree where a grizzly I attacked him. 238 62 "It would be fitting, I think, if among the last manmade tracks on earth could be found the huge footprints of the I great brown bear."(Earl Fleming, 1958). 242 I ix I I I Tables , I Minimum numbers of grizzly bears observed in M t. I McKinley National Park, 1939-1970. 15 I 2 Frequency of litter sizes at different ages observed in grizzly I bears in Mt. McKinley National Park. 21 I 3 Minimum numbers of families of one, two, and three cubs observed in Mt. McKinley Park, 1922-1970. 22 4 Measurements of grizzly bear tracks. 26 I 5 Summary of home-range data for grizzly bear families seen for two or more summers. 38 I 6 Average length of nursing and nursing interval for families with cubs of different ages. 103 7 Tabulation of foods eaten by grizzlies from observations of I feeding, 1945-1970. 136 8 Occurrence of food items in 810 grizzly bear scats.