An agent-based integrated model of recreational fishing and coral reef ecosystem dynamics for site closure strategy analysis

Abstract

Managing recreational fishing is among the most difficult natural resource management problems. The complex nature of the impacts caused by management changes makes it difficult to identify the full range of ecological and socio-economic effects. It is difficult to distinguish approaches that are effective from those that are not. For example, the evaluation of area closure strategies needs to incorporate the relationships among stock dynamics, angler responses and consequent changes in the geographical distribution of fishing efforts. Empirically-based tools are needed to predict responses to, and outcomes from, management decision that affect fish stocks and fishing benefits. To address this, an integrated agent-based simulation model of recreational fishing and a coral reef system is presented in this paper to evaluate ecological and economic impacts. Angler behaviour is driven by empirically estimated site choice models which link recreational choices to site attributes and angler characteristics. Coral reef ecosystem dynamics is modelled using a local-scale model describing the relationship between fish populations, fishing activities as well as algal and coral cover. We apply the model to the evaluation of area closure strategies. As a case study for this paper, we choose recreational fishing sites from the Ningaloo Marine Park, an iconic coral reef system in Western Australia. The results show that not only the effectiveness but also the distribution of management impacts can be very different from what one would expect without the benefit of integrated modelling. The simulation of a management change on site closure demonstrates the extent to which the often controversial subjects of recreational fishing management can be facilitated using predictive modelling.