Patterns of Cowbird Parasitism in the Southern Atlantic Coastal Plain and Piedmont

Abstract

Until recently, little information was available on patterns of brood parasitism by Brown- headed Cowbirds (Molothrus ater) in the southeastern United States, a region into which cowbirds expanded their range only during the last half of the Twentieth Century and where their abundance is relatively low. We compiled parasitism data from several published and unpublished studies conducted in Georgia and South Carolina from 1993-2000 to examine levels of brood parasitism and determine frequent host species. The combined dataset included 1,372 nests of 24 species reported in the literature to have been parasitized by cowbirds. The parasitism rate on all species combined was 8.2%. Considering only those species that served as hosts in these studies (n = 12), the parasitism rate was 9.3%. Seven species were parasitized at rates

Citation

Kilgo, John C.; Moorman, Christopher E. 2003. Patterns of Cowbird Parasitism in the Southern Atlantic Coastal Plain and Piedmont. Wilson. Bull. 115(3), 2003, pp. 277-284