MEPS 256:99-110 (2003)  -  doi:10.3354/meps256099

Optimal foraging in patchy turbulent environments

Jonathan W. Pitchford1,*, Alex James2, John Brindley3

1Department of Biology, University of York, PO Box 373, York YO10 5YW, United Kingdom
2Department of Science and Mathematics, Sheffield Hallam University, Sheffield S1 1WB, United Kingdom
3Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, United Kingdom

ABSTRACT: The problem of what strategy a predator should adopt when foraging in a turbulent and spatially patchy environment is investigated using simple mathematical models. The study was motivated by the need to understand the behaviour of marine fish larvae searching for copepod prey. It is demonstrated that optimal swimming speed should decrease with increasing turbulence, and that in a patchy turbulent environment it is best to concentrate swimming activity within patches of prey until a threshold of turbulence is exceeded and swimming ceases to be energetically favourable. If the predator is unaware of its global environment, or is only able to make foraging decisions based on temporally and spatially local knowledge, then its ability to forage in a near-optimal manner is severely reduced.

KEY WORDS: Optimal foraging · Turbulence · Patchiness · Fish larvae · Individual-based model

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