Optimization in the ‘Pelagic complex’ : a multi-species competition model of North East Atlantic fisheries

Abstract

Optimal management of herring, mackerel and blue whiting in the North East Atlantic is analyzed. The main motivation is to quantify the potential gain from implementing multi-species management compared to traditional single-species management. The objective is to maximize discounted net revenue; in other words a sole-owner perspective. The results are derived from an empirically based surplus growth type of model with three species. The biological interaction in the model is mainly competition for food. An important result is that discounted net revenue could have been up to 30% higher if the stocks had been optimally managed from a multi-species perspective.