Fish Population Dynamic and Stock Assessment

8.1.1. Introduction

Fish or crustacean or any aquatic population is considered as an integral part of marine ecosystems. The aquatic resources can be made sustainable only if the ecosystem in which living resources live is studied. Hence in ‘ecosystem based fisheries management, the impacts of fishery on the ecosystem is taken into account.

The ecopath software is used for analysing the tropic reactions in fisheries resource systems. This software could be used to assess the stock in an aquatic system. This model describes the ecosystem at a steady state for a given period. This model is called Eosins as it envisages the steady state ecosystem changes over time, This model incorporates all major components of the ecosystem including the feeding interactions.

Ecopath keeps track of all species and all the feeding interactions within the system at one point of time, while the ecosystem emphasizes the changes in one or more components affecting the ecosystem over time.