Produced by Chris Curnow, Joseph Cooper, Diane Monico, and the Online Distributed Proofreading Team at https://www.pgdp.net USDA FOREST SERVICE RESEARCH PAPER NC-52 1971 [Illustration] Ecological Studies of the TIMBER WOLF in Northeastern Minnesota NORTH CENTRAL FOREST EXPERIMENT STATION FOREST SERVICE U. S. DEPARTMENT OF AGRICULTURE FOREWORD The largest population of timber wolves remaining in the United States (excluding Alaska) lives in northern Minnesota. Many of these wolves inhabit the Superior National Forest, so protecting the habitat of this endangered species is largely a Forest Service responsibility. As the "Age of Ecology" broadens into the 1970's, wolves and wolf habitat will become a subject of concerted research. Forest land managers will have to know more about how the timber wolf fits into a forest system. Building on nearly 50 years of research in northern forests, we at the North Central Station intend to expand our studies of wildlife habitat. We are happy to publish the enclosed papers as one step in this direction. D. B. King, Director North Central Forest Experiment Station D. B. King, Director Forest Service--U.S. Department of Agriculture Folwell Avenue St. Paul, Minnesota 55101 ECOLOGICAL STUDIES OF THE TIMBER WOLF IN NORTHEASTERN MINNESOTA L. David Mech and L. D. Frenzel, Jr. (Editors) CONTENTS Movements, Behavior, and Ecology of Timber Wolves in Northeastern Minnesota L. David Mech, L. D. Frenzel, Jr., Robert R. Ream, and John W. Winship 1 An Analysis of the Age, Sex, and Condition of Deer Killed by Wolves in Northeastern Minnesota L. David Mech and L. D. Frenzel, Jr. 35 The Effect of Snow Conditions on the Vulnerability of White-Tailed Deer to Wolf Predation L. David Mech, L. D. Frenzel, Jr., and P. D. Karns 51 The Possible Occurrence of the Great Plains Wolf in Northeastern Minnesota L. David Mech and L. D. Frenzel, Jr. 60 THE AUTHORS Dr. Mech, formerly with the Department of Biology, Macalester College, St. Paul, Minnesota, is now employed by the U.S. Bureau of Sport Fisheries and Wildlife, Twin Cities, Minnesota. Dr. Frenzel, formerly with the Department of Biology, Macalester College, St. Paul, Minnesota, is now employed by the Department of Entomology, Fisheries, and Wildlife, University of Minnesota, St. Paul, Minnesota. Dr. Ream, formerly with the North Central Forest Experiment Station (maintained in cooperation with the University of Minnesota), Forest Service, U.S. Department of Agriculture, is now employed by the School of Forestry, University of Montana, Missoula, Montana. Mr. Winship is with the U.S. Bureau of Sport Fisheries and Wildlife, Twin Cities, Minnesota.