Response of brown-headed cowbirds to simulated conspecific intruders

• Published in: Animal behaviour Vol. 30; no. 4; pp. 1043 - 1052
• Main Author: Dufty, Alfred M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.1982
• Subjects: Molothrus ater
• ISSN: 0003-3472; 1095-8282
• DOI: 10.1016/S0003-3472(82)80194-2

The response of brown-headed cowbirds ( Molothrus ater) to simulated intruders was examined using playbacks of cowbird vocalizations in conjunction with a model of a male or female cowbird. Females reacted aggressively to female vocalizations but not to male vocalizations. Solitary males approached and often courted the female model but did not approach the male model. Males accompanying females showed little reaction to either model, although some evidence suggests that proximity to the male model may influence their response. These data support the hypothesis that female cowbirds are territorial and that males guard females from the solications of other males. The ecological pressures which may have influenced the development of this social system are discussed.