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Recent recolonization of northwestern Montana by wolves (Canis lupus) provided an opportunity to examine behavioral responses of coyotes (Canis latrans) to a reestablished wolf population. Coyote and wolf annual home ranges overlapped extensively; however, seasonal overlap was not as pronounced. Most seasonal coyote home ranges were located between wolf packs or along the edge of wolf territories, but wolves and coyotes did not use the seasonal overlap area differently than expected. Most of the coyotes maintained random separation distances from wolves, though three coyotes were closer to wolves than expected. No difference in summer activity was found between the canids; however, temporal partitioning occurred during the winter, which may have allowed the increase in home-range overlap observed during the winter. Additionally, temporal partitioning occurred through differential arrangement of canid home ranges (i.e., wolf home ranges were smaller in summer) and reduced overlap of seasonal home ranges. Coyotes were usually singletons and some pairs, and before wolf colonization they fed on lagomorphs and plants. After wolf colonization, coyotes tended to be in pairs and small packs and they relied on ungulates. Although we documented wolves killing coyotes, coyotes are coexisting with wolves through spatial and temporal separation and behavioral changes.

Many studies determine which habitat components are important to animals and the extent their use may overlap with competitive species. However, such studies are often undertaken after populations are in decline or under interspecific stress. Since habitat selection is not independent of interspecific stress, quantifying an animal's current landscape use could be misleading if the species distribution is suboptimal. We present an alternative approach by modeling the predicted distributions of two sympatric species on the landscape using dietary preferences and prey distribution. We compared the observed habitat use of kit foxes (Vulpes macrotis) and coyotes (Canis latrans) against their predicted distribution. Data included locations of kit foxes and coyotes, carnivore scat transects, and seasonal prey surveys. Although habitats demonstrated heterogeneity with respect to prey resources, only coyotes showed habitat use designed to maximize access to prey. In contrast, kit foxes used habitats which did not align closely with prey resources. Instead, habitat use by kit foxes represented spatial and behavioral strategies designed to minimize spatial overlap with coyotes while maximizing access to resources. Data on the distribution of prey, their dietary importance, and the species-specific disparities between predicted and observed habitat distributions supports a mechanism by which kit fox distribution is derived from intense competitive interactions with coyotes.