SHIRAS MOOSE WINTER HABITAT USE IN THE UPPER YELLOWSTONE RIVER VALLEY PRIOR TO AND AFTER THE 1988 FIRES

Abstract

Fourteen radio-collared moose in the upper Yellowstone River drainage of Montana and Wyoming provided information on habitat use patterns during 1987-91. Two basic winter habitat use patterns were evident prior to the 1988 fires in the Yellowstone area. Moose either used willow stands in riparian areas that did not significantly overlap with elk winter range until snow forced them into mature conifer stands, or they used small patches of aspen and willow within elk winter range and retreated to mature conifer stands as these patches were depleted of available browse or covered by snow. Moose that stayed in Yellowstone National Park avoided hunting mortality but may have suffered nutritional penalties by sharing range with elk or by using higher elevation conifer stands with deeper snow. Moose outside thePpark could avoid elk and deep snow more easily but were vulnerable to hunting and faced winter range reduction as mature conifer stands at moderate elevations were logged. Moose that exhibited the high elevation/mature conifer pattern survived extensive burning of their winter ranges by reducing movements and concentrating on small islands of unburned and lightly burned habitat or by shifting home ranges to unburned areas. Moose that shared winter ranges with elk survived the 1988 fires if they were able to avoid excessive movement and find unburned mature conifer stands with snow depths that discouraged elk use.