Biology Letters
Restricted accessPopulation ecology

The effect of social facilitation on foraging success in vultures: a modelling study

Andrew L Jackson

Andrew L Jackson

Department of Zoology, School of Natural Sciences, Trinity College DublinDublin 2, Ireland

[email protected]

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,
Graeme D Ruxton

Graeme D Ruxton

Institute of Biomedical and Life Sciences, University of GlasgowGlasgow G12 8QQ, UK

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and
David C Houston

David C Houston

Institute of Biomedical and Life Sciences, University of GlasgowGlasgow G12 8QQ, UK

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    The status of many Gyps vulture populations are of acute conservation concern as several show marked and rapid decline. Vultures rely heavily on cues from conspecifics to locate carcasses via local enhancement. A simulation model is developed to explore the roles vulture and carcass densities play in this system, where information transfer plays a key role in locating food. We find a sigmoid relationship describing the probability of vultures finding food as a function of vulture density in the habitat. This relationship suggests a threshold density below which the foraging efficiency of the vulture population will drop rapidly towards zero. Management strategies should closely study this foraging system in order to maintain effective foraging densities.

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