An Experimental Translocation of the Eastern Timber Wolf

Part 1

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FOREWORD

The Fish and Wildlife Service is proud to present this bulletin describing an experimental attempt to re-establish an endangered species in part of its native range. Two States, a Federal agency, a university, and two private conservation groups pooled their resources to make the project possible. This effort exemplifies the type of cooperation the Department of the Interior believes is imperative in beginning the gigantic task of trying to save and restore the threatened and endangered animals in this country today.

Our pride is bittersweet, however. The experiment was a complete success in providing the information sought: What might happen when a pack of wolves is transplanted to a new area where the native population has been all but exterminated by Man? It was the answer to this question that was disappointing. Nevertheless, experiments are for learning, no matter what the answers may be. We are convinced that the answers provided by this project will ultimately be most helpful in future attempts to restore endangered animals to parts of their native ranges where they can begin again on the road to recovery.

DIRECTOR

U. S. Fish and Wildlife Service

Additional Copies Available from

UNITED STATES DEPARTMENT OF THE INTERIOR

FISH AND WILDLIFE SERVICE

REGION 3

Federal Building

Fort Snelling

Twin Cities, Minnesota 55111

AN EXPERIMENTAL TRANSLOCATION OF THE EASTERN TIMBER WOLF

THOMAS F. WEISE Department of Biology Northern Michigan University

WILLIAM L. ROBINSON Department of Biology Northern Michigan University

RICHARD A. HOOK Department of Biology Northern Michigan University

L. DAVID MECH Endangered Wildlife Research Program U. S. Fish & Wildlife Service

Marquette, Michigan 49855

Division of Cooperative Research, Patuxent Wildlife Research Center, Laurel, Md. 20810. Mailing address: North Central Forest Experiment Station, Folwell Ave., St. Paul, MN. 55101.

TABLE OF CONTENTS

FOREWORD Inside front cover

ABSTRACT Back side of title page

INTRODUCTION 1

THE STUDY AREA 2

METHODS 4

RESULTS 8 Social Structure of the Translocated Wolves 8 Aerial Tracking 10 Movements of the Translocated Wolves 11 Post-Release Phase 11 Directional Movement Phase 11 Exploratory Phase 11 Settled Phase 11 Movements of the Remaining Pack Member 11 Movements of Wolf No. 10 12 Feeding Habits 16 Citizen Sightings 17 Habitat Use 19 Failure of Female No. 11 to Whelp 19 Demise of the Translocated Wolves 19

DISCUSSION 21 Effect of Captivity and Human Contact 21 Movements 22 Environmental Influences 22 Possible Homing Tendencies 22 Distances Traveled 23 Home Range Size 25 Selection of a Territory 25 Vulnerability and Mortality 25 Food Habits and Predation 26 An Alternate Approach 26

Part 2

CONCLUSIONS 26

ACKNOWLEDGMENTS 27

LITERATURE CITED 27

ABSTRACT

Two male and two female eastern timber wolves (Canis lupus lycaon), live-trapped in Minnesota were released in March 1974 near Huron Mountain in the Upper Peninsula of Michigan. Their movements were monitored by aerial radio-telemetry.

The wolves separated into a group of three and a single animal after release. The single, a young female, remained in the release region in an area of 346 square miles (896 km²). The pack of three moved generally westward for 13 days and then explored a 1,631 square-mile (4,224 km²) region but settled after 2 months in a 246 square-mile (637 km²) area about 55 miles (88 km) southwest of the release site. The adult female, which mated while captive prior to release, failed to whelp.

In early July, one male was killed by an automobile, and the other was shot. The remaining female from the pack then began to move over a much larger area again. On September 20th she was trapped by a coyote (Canis latrans) trapper and shot. Two months later the single female was killed by a deer (Odocoileus virginianus) hunter.

These results indicated that wolves can be transplanted to a new region, although they may not settle in the release area itself. The displacement of the translocated wolves in this experiment apparently caused an initial increase in their daily movements, and probably increased their vulnerability, at least during the first 2 months after release. The two females examined post-mortem were in good physical condition indicating that food supplies were adequate in Michigan.

Human-caused mortality was responsible for the failure of the wolves to establish themselves. Therefore recommendations for a more successful re-establishment effort include a stronger public-education campaign, removal of the coyote bounty, and release of a greater number of wolves.

INTRODUCTION

The eastern timber wolf (Canis lupus lycaon) originally occurred throughout the eastern United States and Canada but is now extinct in most of the United States. The only substantial population left inhabits northern Minnesota (Fig. 1). The estimated wolf population in the Superior National Forest of northeastern Minnesota in winter 1972-73 was about 390 (Mech 1973), and a tentative population estimate for the entire state is 500 to 1,000 (Mech and Rausch 1975). A well known population of about 15 to 30 wolves is also found in Isle Royale National Park, Lake Superior, Michigan (Mech 1966; Wolfe and Allen 1973; Peterson 1974).

In the Upper Peninsula of Michigan, Hendrickson et al. (1975) estimated the wolf population in 1973 at 6 to 10 animals, existing in three scattered areas: Iron County, Northern Marquette County, and Chippewa and Mackinac Counties (Fig. 2). Lone wolves made up 90 per cent of verified wolf observations there in recent years, and no more than two animals have been found together in at least the past 13 years.

Hendrickson et al. (1975) postulated that the current low wolf population is maintained through possible sporadic breeding and immigration from Ontario and Minnesota (via Wisconsin), but is suppressed by illegal shooting and losses incidental to coyote (Canis latrans) bounty trapping.

The eastern timber wolf was classed as an endangered species in the conterminous United States in 1967 under the Endangered Species Act of 1966. There then followed widespread national and international concern and support for preserving natural wolf populations. Substantial scientific and ethical arguments exist for preventing the extinction of a species or subspecies of any plant or animal. In addition, the presence of the wolf adds immeasurably to a wilderness experience; its esthetic value is incalculable.

Thus in 1970, D. W. Douglass, Chief of the Wildlife Division, Michigan Department of Natural Resources, suggested that restoration of a viable population of wolves in Michigan would be desirable, especially if such efforts could be supported by private organizations. In 1973 the Huron Mountain Wildlife Foundation and the National Audubon Society offered financial support, and we undertook this pilot project to obtain information necessary for a full-scale restoration effort.

The objectives of the research project were to determine whether (1) wild wolves could be moved to a new location, (2) such translocated wolves could remain in the new area, (3) they could learn to find and procure enough food in the new area, (4) they could tolerate and survive human activities, and (5) they would breed and help to re-establish a new population in Upper Michigan.

As background we had the results of three previous attempts to transplant wolves to new areas. In 1952, one male and three female zoo wolves were released on Isle Royale (Mech 1966). They were attracted to humans, became nuisances, and had to be disposed of. Two were shot, one was captured and returned to the mainland, and the male escaped; his fate is unknown.

The second transplant effort took place on uninhabited, 36-square-mile (92 km²) Coronation Island in southeastern Alaska (Merriam 1964; Mech 1970). In 1960, two male and two female, 19-month-old captive wolves, were released there. They learned to prey on black-tailed deer (Odocoileus hemionus columbianus), and multiplied to about 11 members by 1964.

In the third case, two male and three female laboratory wolves from Barrow, Alaska were released near Umiat in August 1972, 175 miles (282 km) southeast of Barrow (Henshaw and Stephenson 1974). Eventually, all moved toward centers of human habitation and three were shot within 7 months. A fourth returned to the pens where she was reared, and was recaptured, while the fate of the fifth wolf remains unknown. Three of the five had taken the correct homing direction.

Because results of the earlier attempts at translocating wolves suggested that pen-reared wolves did not fare well in the wild, we decided to use wild wolves that were accustomed to fending for themselves and avoiding people. They would have to be released in the most inaccessible area we could find and encouraged to stay there. To maximize their chances of breeding, we would have to try to obtain animals with already established social ties, that is, members of the same pack. Approval was obtained from the Minnesota Department of Natural Resources to live-trap up to five wolves in Minnesota, and a permit was granted by the Michigan Department of Natural Resources to release up to five in Upper Michigan.

This bulletin describes the results of the experimental translocation.

THE STUDY AREA

The area selected for the release of the translocated wolves was the Huron Mountain area (Fig. 2) in northern Marquette County in the Upper Peninsula of Michigan (47° N Latitude; 88° W Longitude). This is one of the largest roadless tracts in Michigan, and has one of the lowest year-around densities of resident humans. Much of the area is owned by the Huron Mountain Club, on which accessibility is restricted.

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