The efficiency of adaptive search tactics for different prey distribution patterns: a simulation model based on the behaviour of juvenile plaice |
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Authors: | S. L. Hill,M. T. Burrows, R. N. Hughes&dagger |
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Affiliation: | SAMS, Dunstaffnage Marine Laboratory, P. O. Box 3, Oban, Argyll PA34 4AD, U.K. and;School of Biological Sciences, University of Wales, Bangor, Gwynedd LL57 2UW, U.K. |
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Abstract: | Juvenile plaice Pleuronectes platessa are particularly useful for studying forager search behaviour because their search paths are essentially two dimensional, and punctuated by natural stops. Their prey occur in a range of natural distributions from highly aggregated to over‐dispersed. Juvenile plaice use area‐restricted search near aggregated prey and extensive search, consisting of longer moves and fewer turns, between aggregations and when searching for dispersed prey. They search for less conspicuous prey items mainly in the pauses between movements. This saltatory search behaviour contrasts with the continuous search that is usually assumed in search models. A simulation model of saltatory search behaviour showed that a strategy combining extensive and intensive search allows the efficient exploitation of a range of natural prey distribution patterns, and that it is particularly effective when the search behaviour is controlled by perceived prey density. This allows the predator to respond to the localized aggregations which often occur in nature. The selective use of intensive search was more efficient than the continuous use of extensive search even in prey distribution patterns that were statistically over‐dispersed. |
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Keywords: | area‐restricted search foraging nearest‐neighbour analysis saltatory search simulation model |
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