Can protected areas potentially enlarge viability domains for harvesting management?

We study the viability domains of bio-economic constraints for two different harvesting models. The first model is the classical one introduced by Clark, while the second one brings to the fore a reserve or protected area. Both dynamics are subject to two constraints: one of ecological type ensuring a minimum stock level, the other one of economic type ensuring a minimum income for fishermen. The goal of this study is to investigate theoretically, with the help of dynamical models, the benefits of creating reserve zones, on both economic and environmental criteria.