Summary: | A non‐linear stochastic model has been proposed and analized for fish harvesting. The model encompasses Gordon–Schaefer model and Pella–Tomlinson model that have been used in the study of extensive data on baleen whales, harp seals and Gulf of St. Lawrence cod. It has been established that the harvesting of those species is more profitable in terms of biomass for which data supports α>2, as compared to that for which α⩽2, where α is general index in the model: $${{\rm d}n(t) \over {\rm d}t} = {rn(t)} {\left[ {1- \left\{{{n(t)} \over {K}} \right\}^{\alpha-1}} \right]}$$ Copyright © 2003 John Wiley & Sons, Ltd.
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