Geographic variation in foraging ecologies of breeding and nonbreeding birds in oak woodlands

Abstract

I studied geographic variation in the foraging ecology of four breeding and four non breeding species in three oak (Quercus spp.) woodlands of California. Variations were evident for all species. Variations in tree-species use, foraging tactics, substrates, and behaviors were species-specific. For example, White-breasted Nuthatches (Sitta carolinensis) used tree species with different frequencies at each study area, although they specialized in where and how they foraged within a tree. The foraging behavior of Yellow-rumped Warblers (Dendroica coronata) varied little among study areas, although they were generalists in their use of trees and in their foraging locations. Because foraging ecologies of birds can be highly site-specific, studies should be conducted at different locations. To preserve site-specific characteristics of a species' foraging ecology, researchers should not pool samples from different geographic locations.

Citation

Block, William M. 1990. Geographic variation in foraging ecologies of breeding and nonbreeding birds in oak woodlands. Studies in Avian Biology. 13: 264-269.