You may download the complete report by clicking the link below: Implant- versus collar-transmitter use on black bears PDF Format (527KB) Gary M. Koehler is a wildlife research scientist with the Washington Department of Fish and Wildlife who recently completed a 7-year field study of black bears. Before joining the department in 1994, he was lecturer in wildlife management at Moi University, Kenya. He received a B.A. in biology from Western Washington University and M.S. and Ph.D. degrees in wildlife management from the University of Idaho. He has studied and published on marten, wolverine, Canada lynx, bobcat, cougar, coyote, African lion, and South China tiger. Gary’s interests include carnivore ecology and international programs for carnivore conservation. P. Briggs Hall is a wildlife veterinarian for the Washington Department of Fish and Wildlife. He received his undergraduate degree from Brigham Young University and D.V.M. from Washington State University. He studied fish diseases and pathology at the University of Washington. Briggs was in private clinical practice for 23 years and has worked for the Department of Fish and Wildlife since 1992. His interests include carnivore, ungulate, and marine mammal diseases. He enjoys biking, backpacking, and other outdoor activities. Mary H. Norton is an associate veterinarian at Kenmore Veterinary Hospital in Kenmore, Washington. She earned a B.S. in biology from Whitman College, an M.A. in zoology from Oregon State University, and a D.V.M. from Washington State University. She has been in clinical practice in small-animal medicine for the past 24 years and has enjoyed the opportunity to work periodically with the Department of Fish and Wildlife since 1994. Her interests include animal behavior, internal medicine and surgery, and habitat conservation. D. John Pierce is currently Chief Wildlife Scientist with the Washington Department of Fish and Wildlife, where he has worked since 1984. He is also a Ph.D. candidate at the University of Washington, developing survey and monitoring techniques using noninvasive DNA sampling techniques. John received a B.S. in wildlife management at the University of Washington and an M.S. in wildlife ecology at the University of Idaho, where he studied moose ecology. His interests include population dynamics, habitat relationships, and exploring ways to involve local communities in collection and analysis of scientific data.

Implant- versus collar-transmitter use on black bears Gary M. Koehler, P. Briggs Hall, Mary H. Norton, and D. John Pierce Reprinted with permission from Wildlife Society Bulletin 2001, 29(2): 600–605 Abstract: Bears are difficult to radiomark for long-term studies because of juvenile growth rates, dramatic seasonal weight changes, and similar head andneck girths for adults. Because collars may be discarded if mounted too loosely or cause neck ulcerations if mounted too tightly, we compared use of collar and implant radiotransmitters for black bears (Ursus americanus) at 3 locations in Washington during 1994–1999. We marked 22 females and 38 males with collar transmitters and 30 females and 40 males with implant transmitters. Marking bears with collars or implants and collecting morphological data and specimens required 20–55 minutes. Amount of Telazol™ used to anesthetize bears marked with collars and to conduct implant surgery and amount of drug used between fall and spring captures differed significantly. Amount of drug did not differ between genders or for bears captured by helicopter or snares. Bears lost collars with cotton breakaway spacers after approximately 21 (±3.4, SE) months in the study area where mean annual precipitation was 52 cm, and 10 (±2.5) months where mean annual precipitation was 200 cm. For bears marked with collars, detection rates (number of radiotelemetry relocations/aerial monitoring session) were similar for males and females and among study areas. In contrast, we detected implant-marked males at lesser rates than females and detected bears at different rates among study areas. Decreased signal strength for implant transmitters resulted in fewer locations and greater search effort for males because they used larger spatial areas and were more difficult to relocate than females. Differences in numbers of relocations obtained for male and female black bears marked with implant transmitters may affect precision of spatial and habitat use estimates and gender comparisons of resource use and mortality rates. For these reasons, implant transmitters may be adequate to monitor animals with small home ranges but may not be appropriate to monitor wide-ranging animals. For more information, see: Living with Washington Wildlife: Black Bear   For more information on wildlife science, please contact WDFW Wildlife Management Program. Phone: 360-902-2515 E-mail: wildthing@dfw.wa.gov Files formatted in Adobe Portable Document Format (PDF) require the Adobe Acrobat Reader to view and print. You can download the free reader directly from Adobe. Windows versions are approximately 4MB in size.

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