Imitating flush-pursue foraging birds : the role of pivoting body movements interspersed between hops during foraging

Abstract

Avian flush-pursuers exploit escape behavior in insects by using displays of spread tails and wings to visually cause insects to escape, when they are pursued by birds in aerial chases. By using simple bird models that approach insects in the bird territories we studied reactions of flies, dragonflies, and two types of moths to the previously unstudied mode of foraging movements comprising displays of the visual patterns, pivoting / pirouetting body movements performed by birds during intermittent pauses between hops along branches or trunks. The results suggest that these pirouetting movements, conspicuously present in flush-pursuing birds, may substantially help the birds to increase the number of prey flushed and available for chase.