Habitat selection and movements of raccoons on a grassland reserve managed for imperiled birds

Abstract

Seasonal habitat selection and foraging movements are important aspects of predator ecology, and individual movements can provide a method to link predator-prey dynamics to the spatial mosaic of the environment. Prairie Ridge State Natural Area in Jasper County, Illinois, is a highly fragmented reserve that provides critical habitat for many declining grassland-dependent birds. Nest predation in this area is likely to be substantial because of high mesopredator populations. We undertook a 2-year telemetry study to investigate raccoon (Procyon lotor) movements and habitat selection on the reserve. During the avian nesting season, raccoon pathways had significantly lower fractal dimension, indicating more linear movements and less searching behavior than for fall-winter pathways. Movement distances and rates did not differ between the sexes or seasons. Habitat selection was significantly different among seasons on 2 hierarchical levels. Raccoons generally avoided grasslands in spring and summer, and the shape of pathways indicated that raccoons apparently did not search for nests in grassland habitats. Consequently, nest predation likely occurred incidentally as raccoons moved across grasslands to richer food patches such as wetlands, streams, and residential areas. © 2007 American Society of Mammalogists.