Biology of the wolverine in central Idaho

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I determined wolverine (Gulo gulo) presence, ecology, spatial characteristics, movement, demographics, social structure, and habitat use in central Idaho from 1992-1995. My study area encompassed approximately 8,000 km2 of primarily roadless and statutory wilderness habitats. The study area was characterized by montane coniferous forests at lower elevations, to high-elevation subalpine habitats associated with talus scree and non-forested mountain tops. Nineteen wolverines were captured and instrumented with intraperitoneal implant transmitters. I monitored wolverines weekly, by ground and aerial telemetry, collecting 1,050 relocations. Annual home ranges of resident adults averaged 384 kmz for females and 1,582 km2 for males. Adult home ranges were segregated by sex, with female home ranges overlapping <10% and male home ranges overlapping <15%. Offspring of both sexes remained associated with the natal area for up to 2 years corresponding with sexual maturation. Juveniles and subadults interacted with resident kin, including their mother, the resident male, and siblings. Evidence of resident adult wolverine associating with subadult wolverine was previously undescribed. Periods of association lasted as long as 7 days with individuals traveling together or localizing at foraging sites. The extended association of subadults and adults may be related to the highly dispersed nature of food resources and may account for large home range sizes of resident females. Adult male home ranges encompassed up to 3 female home ranges. Snow-tracking sessions were conducted to document scent-marking and foraging behavior. Food resources were widely dispersed but consistent in timing and presence which may produce traditional foraging routes. Such sites were revisited within a season of use and between years and were shared within kinship groups. Urination was the primary method of scent-marking observed during this study. The reproductive rate for 4 adult females was less than 1 kit/female/year. Females used secluded high-elevation cirque basins for natal den sites. Human disturbance at maternal dens resulted in den abandonment but not kit abandonment. Kits remained with the adult female for approximately 3 months subsequent to weaning at 9 to 10 weeks of age. Females commonly left dependent kits at rendezvous sites comprised of large boulder talus or riparian areas associated with mature overstory and dense timber deadfall. Boulder talus associated with subalpine habitats was also used for resting and foraging sites. Four male wolverines dispersed at sexual maturity, with 2 emigrating distances greater than 185 km. Two of these individuals appeared to establish at the new location while the other 2 returned to the study area. Seven wolverines died during the study, with predation accounting for 43% of the mortality. Distinct seasonal shifts in elevational use were recorded, with higher-elevational talus/rock cover types preferred during summer months and montane coniferous forest cover types preferred during winter. Wolverines avoided lowland grass/shrub and ponderosa pine (Pinus ponderosa) cover types. Movement to lower elevations during winter months may be correlated with increased presence of carrion attributable to the fall big game hunting seasons. Ungulate species including mule deer (Odocoileus hemionus), elk (Cervus eluphus), moose (Alces alces), and domestic cow (Bos bos) and horse (Equus sp.) were present at similar proportions in both summer and winter scat and foraging site collections. Other prey items included 5 species of carnivores; 12 rodent species, including 5 sciurids; and 1 lagomorph species. Avian species constituted 4.9% of species occurrences while insects, primarily ants, occurred at 5.9%.

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ELECTRONIC FILE - Zoology

Generic citation: Copeland, J. P. 1996. Biology of the wolverine in central Idaho. Unpublished thesis, University of Idaho, Moscow. 138 pp.

SWAP (2/19/2016) citation:
Copeland JP. 1996. Biology of the wolverine in central Idaho [master's thesis]. Moscow (ID): University of Idaho. 138 p. [accessed 2016 Feb 8]. https://www.researchgate.net/profile/Jeffrey_Copeland/publication/345380....