The impact of predation by red-winged blackbirds on European corn borer populations

Abstract

Population estimates of the European corn borer (Ostrinia nubilalis Lepidoptera: Pyralidae) were significantly positively correlated with distance from a blackbird roost near Beauharnois, Quebec. Gullet contents of male red-winged blackbirds (Agelaius phoeniceus) indicated that corn borers were consumed, particularly in the late fall. This predation appears to be responsible for lowering corn borer populations in standing corn the following year. It was estimated that the benefit provided by red-winged blackbirds through predation on com borers compensated for approximately 20% of the damage the birds did to standing corn.