In this paper, maximum sustainable yield policy in prey-predator system is discussed where the prey population follows logistic law of growth. Here a model is proposed involving linear prey–predator interaction and intra-specific competition among predator populations. The growth rate of the predator depends upon predation on the modelled and alternate prey. In traditional prey–predator system, fishing under combined harvesting effort at MSY level may be a sustainable policy, but if MSY does not exist then it is due to the extermination of the predator species only. In MSY level harvesting of one species is sustainable policy. Therefore it can be summed up that MSY (or MSTY) policies in prey predator models are unlikely to fit requirements of biological diversity conservation in all cases.

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Maximum Sustainable Yield Prey Predator Harvesting Effort Intraspecific Compition.