Habitat features associated with predation of New England cottontails: What scale is appropriate?

Abstract

We examined habitat features at several spatial scales that were associated with predation of New England cottontails (Sylvilagus transitionalis) by mammalian carnivores. The fate (killed or survived) of marked cottontails was compared with the characteristics of the habitat patch they occupied and composition of the surrounding landscape. The perimeter-to-area ratio of an occupied patch, the amount of disturbed habitat within 0.5 km of a patch, and the amount of coniferous forest within 1 km of a patch were greater for killed rabbits than for those that survived. The amount of water within 1 km and an index of landscape evenness were greater for rabbits that survived. Habitat features in the vicinity of patches occupied by cottontails apparently influenced the distribution and movements of carnivores. Characteristics of patches likely influenced rabbit exposure and predator success. We propose that predation of cottontails was a multiscaled process. Landscape composition (ca. 250 km2) influenced the relative abundance of predators. The distribution of predators within a landscape was a function of the distribution of life requisites (multiple patches, ca. 250 ha). Predators then selected a patch in which to forage on the basis of its relative productivity compared with adjacent patches. Finally, once a predator entered a patch, the vulnerability of a resident cottontail was dependent on the site (ca. 250 m2) occupied by the rabbit. This hierarchical approach may help resolve the current debate on the risk of predation in fragmented landscapes.