title: Quorum decision-making in foraging fish shoals.
abstract: Quorum responses provide a means for group-living animals to integrate and filter disparate social information to produce accurate and coherent group decisions. A quorum response may be defined as a steep increase in the probability of group members performing a given behaviour once a threshold minimum number of their group mates already performing that behaviour is exceeded. In a previous study we reported the use of a quorum response in group decision-making of threespine sticklebacks (Gasterosteus aculeatus) under a simulated predation threat. Here we examine the use of quorum responses by shoals of sticklebacks in first locating and then leaving a foraging patch. We show that a quorum rule explains movement decisions by threespine sticklebacks toward and then away from a food patch. Following both to and from a food patch occurred when a threshold number of initiators was exceeded, with the threshold being determined by the group size.
authors.affiliation: Department of Biology, University of Leicester, Leicester, United Kingdom. ashleyjwward@gmail.com
authors.forename: Ashley J W
authors.initials: AJ
authors.lastname: Ward
authors.forename: Jens
authors.initials: J
authors.lastname: Krause
authors.forename: David J T
authors.initials: DJ
authors.lastname: Sumpter
mesh_terms: D000819:Animal Communication; D000818:Animals; D003657:Decision Making; D008960:Models, Psychological; D011235:Predatory Behavior; D023701:Smegmamorpha / Q000502:physiology*