RED-EYED VIREOS HAVE DIFFICULTY RECOGNIZINGINDIVIDUAL NEIGHBORS’ SONGS

I investigated recognition of individual neighbors’ songs in a migratory species with large repertoires, the Red-eyed Vireo (Vireo olivaceous). To test for abilities to recognize individual neighbors, I measured responses to playbacks of neighbors songs from appropriateand inappropriate boundaries in two different years. Because the responses to the two typesof playbacks were not statistically different in either year, I concluded that Red-eyed Vireos have difficulty recognizing their neighbors by song. If recognition of neighbors serves to reduce energy expended in territorial defense during the breeding season, a large repertoire could be costly to male Red-eyed Vireos.

RENEE GODARD, The Auk 110(4):857-862, 1993