Shadows on the Snow: Following Winter's Wolverines

By Diane Evans Mack, Idaho Department of Fish and Game After eight months of quiet inactivity, small log cabins are back in service in the wilds of central Idaho. But don't expect to make a reservation for a back-country ski vacation; these cabins are not for human guests. They're designed to entice hungry or just plain curious wolverines to hop in, tug on some bait and close the lid on themselves. In doing so, these enigmatic animals become key players in a research study initiated last winter in the Payette National Forest to examine the interactions between winter recreation and wolverines. Wolverines roam the wilder, more remote areas of Idaho. They're built for snow, from their thick fur to their large paws. When other animals hibernate or retreat to lower elevations in winter, wolverines remain and make a living in their harsh environment by uncovering carcasses or bones buried under snow. However, there is concern that remote areas wolverines occupy are no longer truly remote in winter due to increasing recreational activity. This changing human presence potentially could affect wolverines, especially where females are denning or raising their young, known as kits. A research project looking at this question is led by Kim Heinemeyer of Round River Conservation Studies and John Squires of the U.S. Forest Service Rocky Mountain Research Station. Idaho Department of Fish and Game is a partner, as are the Payette, Boise and Sawtooth national forests, Idaho State Snowmobile Association, Central Idaho Recreation Coalition, Brundage Ski Area, University of Montana, The Wolverine Foundation, and Valley County. Tracking wolverines is one piece of the puzzle. Winter recreationists are the other. Last year, back-country skiers and snowmobilers voluntarily wore small GPS data loggers and contributed over 700 individual tracks that mapped where and when they traveled. When overlaid on the movements of six collared wolverines, these data began to show how these groups interact. Yet this kind of study requires several years in multiple locations. Thus begins year two. On the Sawtooth National Forest, remote cameras and hair snagging brushes are collecting wolverine images and DNA as a first step to trapping next year. The Payette National Forest study area was expanded to the Warm Lake area of the Boise National Forest, and already two new wolverines, an adult male and an adult female, are Ôon the air' with radio collars. And north of McCall, five of the six animals captured last year survived the summer and fall and were recaptured and collared again. Two new animals in this area also have been collared, one of which may be a kit from one of last year's female study animals. Nine wolverines and a busy recreation season made for an amazing first month. Field work will continue through April, when the animals will be captured again to remove collars and relinquish their data. To learn more about the study, contact idahowolverine@gmail.com. Diane Evans Mack is regional wildlife biologist in the Southwest Region.