Seasonal habitat relationships of white-tailed deer in northwestern Montana

Seasonal components of white-tailed deer (Odocoileus virqinianus) habitat were determined in northwestern Montana.Sixteen radio collared adult female deer were located throughout the summers and winters of 1986 and 1987.Sixteen deer summer ranges and 15 winter ranges were delineated.Summer home ranges were estimated by the minimum convex polygon method.Winter ranges were estimated using radio locations, and personal knowledge of the habitat and the animals concerned.Harmonic mean measures were used to delineate core areas within summer ranges.Habitat characteristics were determined by systematically sampling 208 points on deer summer ranges and 195 points on winter ranges.In addition, 208 points were sampled in 16 random areas to describe available habitat within the study area.Discriminant function models for summer habitat selection by deer were developed from measured habitat characteristics within deer summer ranges and random areas.White-tailed deer summer ranges contained earlier successional stages, were located nearer to running water, and had less Douglas-fir (Pseudotsuqa menziesii) saplings and poles/ha than random areas.Deer ranges ware also closer to roads, had gentler slopes, less deadfall, greater forb cover, and more hardwood poles/ha.The Chi-square goodness-of-fit test and Bonferroni Z confidence intervals showed a selection (P < 0.05) for moist habitat types.Deer used western aspects less than expected (P < 0.05) based upon availability.Deer summer ranges had significantly (P < 0.05) more edge than random areas.Selected summer habitats of white-tailed deer were riparian areas composed of a mosaic of different habitats.Within the hone range, discriminant models revealed that core areas had higher pole densities/ha, were located farther from trails, had more edge, and gentler slopes than non-core areas.Core areas were also closer to roads, and had higher densities of lodgepole pine (Pinus contorta) poles and hardwood saplings.Selected areas within summer home ranges had dense hiding cover in association with an edge that was located away from trails.Discriminant function models revealed that white-tailed deer winter ranges were located at lower elevations, had more edge, and higher forest canopy cover than randan areas.Deer winter ranges also had lower pole densities/ha, more Douglas-fir saplings, and more mature hardwood and spruce (Picea spp.) trees/ha.Deer selected {P < 0.05) level/gently rolling terrain in valley bottoms, and used southern and western aspects less than expected (P < 0.05) based upon availability.Selected winter habitats of white-tailed deer were mature bottomland forest communities (P < 0.05) which provided shelter in close proximity to small openings.