title: Benefits of foraging in small groups: An experimental study on public information use in red knots Calidris canutus.
abstract: Social foraging is common and may provide benefits of safety and public information. Public information permits faster and more accurate estimates of patch resource densities, thus allowing more effective foraging. In this paper we report on two experiments with red knots Calidris canutus, socially foraging shorebirds that eat bivalves on intertidal mudflats. The first experiment was designed to show that red knots are capable of using public information, and whether dominance status or sex affected its use. We showed that knots can detect the foraging success of conspecifics and choose a patch accordingly. Neither dominance status nor sex influenced public information use. In the second experiment, by manipulating group size, we investigated whether public information use affected food-patch discovery rates and patch residence times. We showed that the time needed before locating a food patch decreased in proportion to group size. Also, an individual's number of patch visits before locating the food declined with group size, and, to our surprise, their average patch residence time did as well. Moreover, knots differed in their search strategy in that some birds consistently exploited the searching efforts of others. We conclude that socially foraging knots have the potential to greatly increase their food-finding rate by using public information. This article is part of a Special Issue entitled: In Honor of Jerry Hogan.
authors.affiliation: Department of Marine Ecology, NIOZ Royal Netherlands Institute for Sea Research, 1790 AB Den Burg, Texel, The Netherlands. Electronic address: allert.bijleveld@gmail.com.
authors.forename: Allert I
authors.initials: AI
authors.lastname: Bijleveld
authors.affiliation: Department of Marine Ecology, NIOZ Royal Netherlands Institute for Sea Research, 1790 AB Den Burg, Texel, The Netherlands.
authors.forename: Jan A
authors.initials: JA
authors.lastname: van Gils
authors.affiliation: Department of Marine Ecology, NIOZ Royal Netherlands Institute for Sea Research, 1790 AB Den Burg, Texel, The Netherlands.
authors.forename: Jeltje
authors.initials: J
authors.lastname: Jouta
authors.affiliation: Department of Marine Ecology, NIOZ Royal Netherlands Institute for Sea Research, 1790 AB Den Burg, Texel, The Netherlands; Chair in Global Flyway Ecology, Animal Ecology Group, Centre for Ecological and Evolutionary Studies (CEES), University of Groningen, PO Box 11103, 9700 CC, Groningen, The Netherlands.
authors.forename: Theunis
authors.initials: T
authors.lastname: Piersma
mesh_terms: D000819:Animal Communication; D000818:Animals; D000066949:Biobehavioral Sciences; D046091:Charadriiformes / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology* / Q000523:psychology*; D033181:Information Dissemination; D012919:Social Behavior
keywords: Animal personality; Consistent individual differences; Inadvertent social information; Local enhancement; Producer–scrounger games; Social foraging