Nonlethal predator effects on the turn-over of wild bird flocks.

ABSTRACT: Nonlethal predator effects arise when individuals of a prey species adjust their behaviour due to the presence of predators. Non-lethal predator effects have been shown to affect social group structure and social behaviour as well as individual fitness of the prey. In this experimental study, we used model sparrowhawks to launch attacks on flocks of wild great tits and blue tits whilst monitoring their social dynamics. We show that nonlethal attacks caused instantaneous turn-over and mixing of group composition within foraging flocks. A single experimental 'attack' lasting on average less than three seconds, caused the amount of turn-over expected over three hours (2.0-3.8 hours) of undisturbed foraging. This suggests that nonlethal predator effects can greatly alter group composition with

SUBMITTER: Voelkl B 

PROVIDER: S-EPMC5025840 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature