We propose a dynamic model for studying the time evolution of fish stocks in an environment divided into two adjacent zones with different fishing policies. We analyze two particular harvesting methods: constant fishing effort and profit maximization. In this case, some agents engage in competition based on maximization of individual profit whereas others cooperate. The asymptotic behavior of t...

Previous models of marine protected areas (MPAs) have generally assumed that there were no existing regulations on catch and have frequently shown that MPAs, by themselves, can be used to maintain both sustainable fish stocks and sustainable harvests. We explore the impact of implementing an MPA in a spatially structured model of a single-species fish stock that is regulated by total allowable ...

Resumen Spillovers can significantly reduce or enhance the effects of land-use policies, yet there exists little rigorous evidence concerning their magnitudes. We examine how national parks within Costa Rica affect the clearing of forest nearby. We find that average deforestation spillover impacts are not significant within 0-5km and 5-10km rings around parks. However, we argue that this averag...

Socioeconomic and ecological analyses of eleven coral reef conservation efforts make clear that marine protected areas are not the answer, and that in fact support of local communities is far more important than some government mandated 'fishing closure'. Apparently there are marine 'paper parks' just as there are terrestrial 'paper parks'.