A bio-economic application to the Cape Rock Lobster resource using a delay difference modelling approach

Abstract

In many species, like the Cape Rock Lobster (Jasus lalandii), the life cycles of males and females differ. This may motivate the use of two-sex models in a stock-assessment analysis. It is also true for this resource, that juveniles do not reach sexual maturity immediately. Therefore a delay-difference model is appropriate. In this study we follow a bio-economic approach and use a two-sex delay-difference model to determine a maximum economic yield strategy. Thus we determine an economic optimum steady state solution at which to harvest this resource subject to the biological constraints of the species.

Keywords: delay-difference, bio-economic, bifurcation, recruitment, harvesting, optimal policy


ORiON Vol. 20 (1) 2004: pp. 7-28