Is time partitioning the currency of coexistence for a grassland canid community?

Abstract

Habitat and diet preferences are often considered major aspects of niches differentiation among species; however, partitioning of habitat and resource use temporally is often overlooked in modeling coexistence. The plasticity of temporal activity patterns of individuals may influence the species’ response to selective forces and long-term persistence. Temporal avoidance may be a mechanism by which subordinate species can reduce the likelihood of direct competition with dominant sympatric species. Here, we examine temporal activity patterns of three canid species (swift fox Vulpes velox , red fox Vulpes vulpes and coyote Canis latrans ) to determine how temporal activity patterns and activity overlap varies among species. We found that all species presented seasonal differences in activity patterns. When activity patterns were compared among species, the estimates of activity overlap in the spring season (i.e. breeding and pup-rearing periods) were higher than the activity patterns in the fall (i.e. juvenile dispersal and pair-formation periods); however, activity pattern overlap among species was significant only during the fall. Overall, these patterns revealed a close temporal overlap between swift fox (subordinate species) and both red fox and coyote (dominant species), which provides insight into conditions under which time partitioning may not be as clear as predicted, and other mechanisms may facilitate species coexistence. Considering swift fox population decline and distribution contraction across the North American grasslands, investigating temporal activity patterns of the canid species may reveal the implications of altering such patterns for individual animals, populations and ecosystems.