Physical Characteristics of Arctic Fox (Alopex lagopus) Dens in Northern Yukon Territory, Canada

Physical characteristics of arctic fox (Alopex lagopus) dens on Herschel Island and the Yukon Coastal Plain, Yukon Territory, Canada, are described. The preferred den habitat on Herschel Island is characterized by moderately eroded, sloping, gullied terrain, where foxes select sandy erosional mounds for denning. The preferred habitat on the Yukon Coastal Plain is fluvial landforms, where foxes select streamside cutbanks and occasional dunes for den location. Dens are generally associated with relatively warm, well-drained landscape positions. Burrow entrances are significantly oriented toward the south (P<0.0025). Soils of dens are coarse textured, typically sandy loam to sand. Depth to permafrost is significantly greater under the den than at adjacent sites (p<0.02). Certain unique soil profile characteristics, particularly the replacement of common cryoturbation (frost churning) features with those zooturbation (faunal mixing) and the formation of humus-rich surface horizons, appear to be the result of denning activities by foxes. Observed differences in soil temperature and depth to permafrost between den site soils and adjacent soils have likely been caused, at least in part, by denning activities.Key words: arctic fox (Alopex lagopus), dens, soil characteristics, habitat, distribution, northern Yukon TerritoryMots clés: renard polaire (Alopex lagopus), renardières, caractéristiques du sol, habitat, distribution, nord du Yukon&nbsp

A Land Capability Classification System for Beaver (Castor canadensis Kuhl)

Beaver colony site density was sampled on 136 lakes (about 1830 shoreline km) and 45 stream sections (145 stream km) in the northern interior of British Columbia. Beaver habitat factors were quantified and then related to beaver colony site density by multiple regression analysis. On the basis of separate analysis for lakes and streams, a land capability classification system was developed for beaver. The regression equations are also useful as models of beaver-habitat relationships and can be used for beaver inventory by prediction of beaver colony site density. Conservation of existing aspen (Populus tremuloides) stands, common throughout the bea- ver\u27s range, is considered the most powerful management tool for maintaining or enhancing present beaver land capabilit