Species enrichment and its consequences on the sustainability of an exploited prey-predator system

Abstract

In population ecology, in particular the predator-prey interaction with variable biotic resource can produce more complex dynamics including extinction, periodic solution and switching of stability. One of the mentionable criterion of the present prey predator model is asymmetrical
intraguild predation, where a common resource are consumed by two competitive species and at the same time one consume the other. The intraguild predator secures both the benefits of feeding and removing a potential contender. Our article describes the ecology of an exploited prey predator system with variable biotic resource and we observe a transcritical bifurcation occurs at certain level of enrichment. We investigate the impacts of
harvesting of both prey and predator species separately and again simultaneously under independent effort strategy at global MSTY level. We also explore the successful harvesting strategy corresponding to intermediate and high development rate of biotic resources from both yield maximization and species conservation viewpoint. In particular, intermediate enrichment can improve MSY policy. The most interesting result is that in a highly enriched environment, in spite of the increase of predator density, the maximum sustainable total yield decreases following the decreasing prey density.