Do Begging Calls From Nestling Red-Winged Blackbirds (Agelaius phoeniceus) Increase Nest Predation?

Abstract

ABSTRACT I used 20 years of nest records and predation at silent control and begging-call playback nests to determine whether begging calls of Red-winged Blackbirds (Agelaius phoeniceus) attract predators. Survival analysis provided no evidence that vocal begging affected nest predation. Survival schedules during egg and nestling periods were not significantly different, and vocal begging activity was not significantly correlated with daily nest survival. I found that predation at 35 no-longer-active nests at which begging calls were played at natural volume, at a typical rate, and following a normal schedule was slightly but not significantly higher than at 35 silent control nests. Selection may have favored adaptations of nestling Red-winged Blackbirds' begging calls that reduce the risk of predation.