Wing-Flashing by Northern Mockingbirds While Foraging and in Response to a Predator Model

Abstract

Some insectivorous avian species may improve foraging success by flashing conspicuously colored wing patches or tail spots to startle potential prey and elicit escape behavior. While some studies of Mimus polyglottos (Northern Mockingbird) suggest that wing-flashing (WF) behavior may enhance strike rate and/or foraging success, other studies are equivocal or suggest a negative relationship. Anecdotal observations suggest that WF in mockingbirds may serve an additional role, as this behavior has been documented in response to a potential predator. The biological roles of WF remain unclear in Northern Mockingbirds; thus, we sought to systematically study: (1) the seasonal use of WF while foraging, and (2) the behavioral response of mockingbirds when presented with 2 model organisms—a nest predator and a neutral avian species. We found that foraging bouts during the reproductive period were more likely to include WF than those during the non-reproductive period, but that there was no significant relationship between WF rate and either strike rate or foraging-success rate. When exposed to models, mockingbirds only employed WF during the reproductive period, and then, only to the predator model. Our results suggest that WF is confined primarily to the reproductive period of the annual cycle, and that this behavior is utilized while foraging and in response to the presence of a potential predator. However, the biological role WF plays in both of these circumstances bears further examination.