PREDICTING WHITE-TAILED DEER HABITAT USE IN NORTHERN IDAHO

Winter habitat use patterns of white-tailed deer (Odocoileus virginian us) have been studied extensively across their northern distribution. However, previous research has contributed little to predicting habita t use of unstudied populations. Thus, we evaluated winter habitat use of white-tailed deer in the Priest River drainage of northern Idaho an d developed a predictive model of winter habitat selection. Our findin gs suggest that winter habitat selection is predictable given seasonal changes in basal metabolism and the effects of snow accumulation on f orage availability and energy expenditure. During early (18 Nov-8 jan) and late (3 Mar-2 Apr) winter, when basal metabolic rates were elevat ed and snow depths did not exceed 30 cm, white-tailed deer selected lo dgepole pine (Pinus contorta) and Douglas-fir (Pseudotsuga menziesii) pole timber stands that provided the greatest availability of preferre d forage species. During mid-winter (9 Jan-2 Mar) when snow depths exc eeded 40 cm and basal metabolism was depressed, white-tailed deer sele cted western red cedar (Thuja plicata) and western hemlock (Tsuga hete rophylla) old growth forest stands characterized by depauperate unders tories, dense canopy cover, and low snow accumulation. We analyzed thi s relationship with logistic regression, which provided a biologically meaningful model of winter habitat selection that could be applied to predict habitat selection patterns of unstudied populations. Our data suggest that in northern Idaho and on other white-tailed deer winter ranges where snow depths commonly exceed 40 cm, habitat managers shoul d provide old growth forest, or mature second growth stands with simil ar structural attributes to satisfy winter habitat requirements.