MIDWEST FURBEARER MANAGEMENT MIDWEST FURBEARER MANAGEMENT Edited by Glen C. Sanderson, Head Section of Wildlife Research Illinois Natural History Survey Proceedings of a Symposium held at the 43rd Midwest Fish and Wildlife Conference, Wichita, Kansas 7-8 December 1981 1982 Sponsored by North Central Section, Central Mountains and Plains Section, and Kansas Chapter of The Wildlife Society Library of Congress Catalog Card Number 83-080045 The Kansas Chapter of The Wildlife Society acknowledges the contributions made by the following companies and individuals toward the publication of the 1981 Furbearer Symposium proceedings. Without this generous support, the Chapter would have had difficulty meeting its goal of promoting sound wildlife management in Kansas and throughout the Great Plains. Steven G. Sorensen, President Kansas Chapter, The Wildlife Society Alaskan Fur Co., Inc., 9029 Metcalf, Overland Park, KS Don Gerhardt, Gerhardt Fur Co., 102 West 47th, Kansas City, MO Neil Johnson, P.O. Box 284, Pratt, I(S Darrell Montei, 532 Sunrise, Pratt, KS Kent Montei, 901 South Pearl, Pratt, KS Charles Morgan, 3025 East Avenue South, La Crosse, WI Steven G. Sorensen, 808 West 5th, Concordia, KS Robert Wood, 502 Commodore, Pratt, KS The Central Mountains and Plains Section of The Wildlife Society acknowledges the contributions made by the following companies, individuals, and agencies toward the publication of the 1981 Furbearer Symposium proceedings. Colorado Chapter, The Wildlife Society Joseph Hnatiuk, Saskatoon, Saskatchewan Dean Hoffman, Central States Furs Corp., Aurora, IA North Dakota Chapter, The Wildlife Society Northwoods Import-Export, Greensburg, PA O'Gorman Enterprises, Inc., Broadus, MT South Dakota Chapter, The Wildlife Society Charles Flora: Art Director and Designer Office of Printing Services University of Illinois at Urbana-Champaign ABOUT THE BOOK The seed from which this symposium sprouted was sown during a Midwest Furbearer Workshop, held in Manhattan, Kansas, in April 1979. At this informal gathering of midwestern biologists, it was evident that interest and activity in furbearer manage­ ment had significantly increased as was demonstrated by the large number of new furbearer biologists present, representing states that had just upgraded their programs. The need for enhanced communication among the group was expressed unanimously, and the concept of a special furbearer management program was developed. Later in 1979, during the Midwest Fish and Wildlife Conference in Champaign, Illinois, strong interest was shown in using the biennial symposium sponsored by the North Central Section of the Wildlife Society as a means to bring the furbearer biologists and managers together again and share their information with the rest of the wildlife com­ munity. We, as co-chairmen, had no trouble finding willing participants and an anxious audience. The format and subject matter of the symposium were developed by us with much advice from state, federal, and university biologists, but the faults and omis­ sions are ours. The initial papers are reviews of techniques necessary to carry out progressive furbearer management programs: census techniques, aging and tooth histology, productivity measurements, and harvest surveys. Two papers deal with the use of scientific information to interpret population phenomena. The 3 papers that follow address some special problems relating to the fur resource: identifying the resource users, the fur marketplace, and rabies. Next, the history of the red fox describes how people and management can interact with a valuable furbearer. The paper on reintroduction of mustelids reviews information from diverse sources on what is becoming a population management practice. The final paper is a historical overview and a discussion of the future of furbearer management in the Midwest, pointing out some of the major problems that may face managers in-years to come. Some of the information presented in these papers is restricted to the Midwestern states and provinces: North Dakota, South Dakota, Nebraska, Kansas, Missouri, Iowa, Minnesota, Wisconsin, Illinois, Michigan, Indiana, Ohio, Ontario, and Manitoba. None­ theless, we hope professionals and students interested in the management of furbearers throughout North America will find it useful. #14~ Neil F. Johnson Furbearer Project Leader Kansas Fish and Game &!~ Assistant Professor School of Forestry, Fisheries andWildlife University of Missouri-Columbia FOREWORD Furbearers have always attracted special management interest because they are among the few species of wildlife that have a legal trade value in North America. This interest has intensified in recent years because pelts of certain species have been particularly valuable and methods of taking fur have become controversial. The time was ripe for furbearer biologists to meet and review current management problems and programs. A Iurbearer management symposium was originally proposed by the Kansas Chapter of The Wildlife Society to be held in conjunction with the 43rd Midwest Fish and Wildlife Conference at Wichita. The North Central Section offered to co-sponsor the symposium in keeping with its objective (since 1965) of conducting biennial symposia. The Central Mountains and Plains Section provided some financial assistance. So, a unique opportunity was present for sub-units of The Wildlife Society to cooperate in an effort to disseminate information on furbearer management. The final result is this book. It is evident that the symposium chairmen, authors, and editor have done their work well. Like many cooperative ventures, this symposium was a success because of effective teamwork. The contents of this book should be useful to wildlife workers for many years. Hopefully, the main beneficiaries will be the furbearing mammals of the Midwest. Northcentral Section The Wildlife Society President Kansas Chapter The Wildlife Society President Central Mountain & Plains Section The Wildlife Society The pen and ink drawings used at the beginning and ends of the chapters were drawn especially for this publication by Beverley C. Sanderson, Champaign, Illinois. Charles W. Schwartz, formerly with the Missouri Department of Conser­ vation, provided the pen and ink drawing used in the program for the symposium and as the Frontispiece for this publication. Both artists donated the use of their drawings, and we thank them for their contributions. PREFACE The role of Iurbearers in the settlement of North America is well known and several major studies dealing with furbearers were published prior to 1950. Furbearers in the Midwest and in much of North America received little attention from researchers, managers, and administrators from the late 1940's through the 1960's. Interest in furbearers increased rapidly in the 1970's with dramatic increases in pelt prices, an increased awareness of the values of all wildlife, endangered species legislation, increased de­ mands for outdoor recreation, and the development of antihunting and antitrapping sentiment. This symposium is one result of the increased interest in furbearers in the Midwest. This symposium was organized by Neil F. Johnson and Erik K. Fritzell. We thank Eva Steger for editorial assistance and Elizabeth Anderson and Cynthia Jackson for retyping some of the manuscripts; all are with the Illinois Natural History Survey. We give a special thanks to the individuals who reviewed the manuscripts. They were: Ernest D. Ables, Stephen H. Allen, Major L. Boddicker, William L. Clark, William R. Edwards, David W. Erickson, Larry Frederickson, Erik K. Fritzell, Lonnie P. Hansen, George F. Hubert, [r., Douglas H. Johnson, Neil F. Johnson, Stephen R. Kellert, W. D. Klimstra, Carl O. Mohr, Tony J. Peterle, Charles M. Pils, Ernest E. Provost, Alan B. Sargeant, Howard J. Stains, G. L. Storm, B. J. Verts, and Vernon Wright. Thirteen papers were presented during the symposium. The theme was management of furbearers in the Midwest, but several reports include information from beyond this geographical area. Twelve of the papers presented at the symposium are included in these proceedings. Only the abstract of the remaining report is included as the authors failed to submit a completed manuscript. Financial support for publication of this book was provided by the North Central Section, Central Mountain and Plains Section, and Kansas Chapter of The Wildlife Society. Success of the symposium can be measured by the large attendance registered at the sessions, the enthusiasm of the speakers, and the quality of the papers presented. Because of that success, special recognition is warranted for those individual society members who volunteered their time to serve on the committees and many work details necessary to organize and coordinate the symposium. We also recognize Mr. George Gragg of Gragg Furs International of Wichita and the Kansas Fish and Game Commission, whose significant financial support of the Kansas Chapter made their part in hosting the symposium possible. CONTENTS 1 A Perspective on Furbearer Management 1 Eril~ K. Fritzell, Nell F. Johnson 2 Review of Population IndicesApplied in Furbearer Management 11 William R. Clerk, Ronald D. Andrews 3 Population Modeling for Furbearer Management 25 Douglas H. Johnson 4 Assessing Productivity of Furbearers 39 Neil F. Payne 5 Estimating and Using Furbearer Harvest Information 53 David W. Erickson 6 Techniques for Aging Furbearers Using Tooth Histology 67 D. H. Johnston, I. D. Watt, D. Joachim, M. Novok. S. Strathearn, M. Stricklond