Ecology of white-tailed deer on summer-fall range in northcentral Idaho

Abstract

Home range size, migration patterns, and habitat use were determined for white-tailed deer (Odocoileus virginianus) in a coniferous forest of northcentral Idaho. Sixty-nine deer of both sexes were radio-collared and monitored during daytime hours in summer-fall of 1990 and 1991. Summer-fall home range size for male deer (n = 14) averaged 76 ha (SD = 40). Sumner, fall, and summer-fall average activity radii for male deer averaged 0.33 km (SD = 0.08), 0.34 km (SD = 0.17), and 0.40 km (SD = 0.12), respectively. Distances between 1990 and 1991 summer-fall geographic activity centers averaged 0.31 km (SD = 0.25). On average, summer-fall home ranges in 1991 encompassed 44% (SD= 32) of 1990 home ranges. Fall migration distances averaged 38 km (SD = 8) in 1990 and 39 km (SD= 9) in 1991. Deer migrated, on average, in 4 days (SD = 2) and 7 days (SD = 4) to the winter range in 1990 and 1991, respectively. Two subpopulations of deer that differed in respect to date of departure from the summer-fall range and average migration distance were identified. Departure dates and migration distance were related to migration routes. Topography (slope, aspect, elevation, landform types) influenced habitat use to a lesser degree than vegetation structure and composition. Home ranges were composed of a mosaic of unlogged and logged areas. Deer preferred pole timber and avoided sapling stands, clearcuts, and the moistest habitat types. Relative to fall habitat, summer habitat was characterized by more open-canopied coniferous cover types associated with high forb and shrub cover. Male deer showed no differences in habitat use patterns between prehunt and hunt periods.