Date of Award:
Master of Science (MS)
Department name when degree awarded
Frederick F. Knowlton
Coyotes (Canis latrans) prey upon domestic sheep. The Animal Damage Control (ADC) program currently relies heavily on aerial gunning in winter to control coyote depredations on mountain grazing allotments. Some people claim that winter aerial gunning is not effective because coyotes migrate to lower elevations during winter, following herds of big game animals, and may not be on the allotments where summer depredations occur. I studied the seasonal movement patterns of coyotes in the Bear River Range of Utah and Idaho to determine if coyotes in montane habitats move on a seasonal basis. Radio-collared coyotes were located from fixed-wing aircraft from 13 November 1987 to 15 September 1989.
I used 3 parameters to assess interseasonal movement patterns: overlap in seasonal home ranges, distance between harmonic mean centers of activity, and seasonal differences in mean elevation. All mature coyotes showed overlapping seasonal home ranges, which suggests they did not move substantially between seasons. In contrast, none of the sub-adult coyotes had seasonal home ranges that overlapped. Distances between harmonic centers of seasonal activity were easily assigned to one of two groups (≤5000 m and ≤10,000 m). These corresponded precisely with coyotes that did and did not display overlap in seasonal home ranges. Significant changes in the elevations of seasonal locations were not evident for any age or sex group. I conclude (1) that movement of sub-adult coyotes in the Bear River Range is part of dispersal behavior and is not motivated by seasonal change and (2) that these sub-adult coyotes generally cease wandering during their second years. My findings are similar to other studies where nomadic wandering was more common among sub-adult coyotes and was not correlated with season. I saw no movement of coyotes from the mountains to valley locations. Adult coyotes were in the same location in summer as in winter.
Gantz, Glen F., "Seasonal Movement Patterns of Coyotes in the Bear River Mountains of Idaho and Utah" (1990). All Graduate Theses and Dissertations. 5249.