Conspecific Egg Destruction by a Female Cerulean Warbler

Abstract

Abstract Conspecific egg destruction is an adaptive behavior that has typically evolved in multi-brooded, polygynous, or colonial avian species, and can be difficult to observe. We describe the first case of egg destruction in the Parulidae, which consists of mostly single-brooded and socially monogamous species. In this case, a female Cerulean Warbler (Dendroica cerulea) destroyed 5-day old eggs at a conspecific's nest. This act was likely committed to secure a breeding opportunity with a high quality male or to decrease local competition for resources. There is also the possibility this behavior may have been pathological and not adaptive.