Abstract
Ecological processes near habitat edges often differ from processes away from edges. Yet, the generality of "edge effects" has been hotly debated because results vary tremendously. To understand the factors responsible for this variation, we described nest predation and cowbird distribution patterns in forest edge and forest core habitats on 36 randomly selected plots in three states in the midwestern United States. We tested four hypotheses that may explain the variation and mechanisms responsible for edge effects among the 36 plots: (1) the landscape context, (2) the local predator community, (3) the local bird (host-prey) community, and (4) the nest site microhabitat structure. We used artificial nests baited with quail and clay eggs to determine nest predation patterns and predators and used point count surveys to determine cowbird and host abundance in forest edge and forest core habitats.
Keywords
Brown-headed Cowbirds,
edge effects,
forest songbirds,
habitat landscapes and fragmentation,
host-Cowbird relationships,
Molothrus ater,
nest predation,
predator community
Citation
Donovan, Therese M.; Jones, Peter W.; Annand, Elizabeth M.; Thompson III, Frank R. 1997. Variation in Local-Scale Edge Effects: Mechanisms and landscape Context. Ecology. Vol. 78 no. 7.:p. 2064-2075. (1997)