Use of Forest Edges by Bats in a Managed Pine Forest Landscape in Coastal North Carolina

Forest edges represent the interface of two vegetation types and often have increased species richness and abundance (edge effects). Edges can affect spatial distribution of species and dynamics of species interactions. Landscapes of intensively managed pine stands are characterized by mosaic-patterning of forest patches and linear forest edges. Managed pine forests are a major landscape feature of the Southeastern U.S., and the effects of intensive pine management on bat communities are poorly understood. Therefore, I examined bat foraging behavior in four structurally distinct stand types (young open-canopy pine, pre-thinned pine, thinned pine, and unmanaged forest) and along forest edges within a managed pine forest landscape in the coastal plain of North Carolina during the summers of 2006 and 2007. At each sampling site, from dusk until dawn, I recorded echolocation calls of bats using Pettersson D240X bat detectors with digital recorders. At each site, I indexed the insect community using malaise insect traps. I captured bats with mist nets to obtain reference echolocation calls. I used negative binomial count regression models to describe bat foraging behavior relative to stand types, forest edges, and availability of insect prey. For all species detected, bat foraging behavior was strongly related to forest edges. Edges were used extensively by six aerial-foraging bat species, but avoided by clutter-tolerant Myotis species. My results emphasize that forest edges are important landscape features in fragmented landscapes