A Dynamic Model of Mesh Size Regulatory Compliance in Fisheries

The violation of fishing regulations is a criminal activity that leads to depleting fish stock levels across the world. This paper focuses on fishing violations in developing countries. In particular, the paper analyses the use of a fishing net with illegal mesh size in a two regimes, namely a management regime where each community claims a territorial use right over the fishery and a regulated open access regime. This paper employs a dynamic model for fishery crimes that involve time and punishment to analyse the use of a net with illegal mesh size in the different regimes. We found that if the community has territorial use right, the illegal activity in addition to decreasing the intrinsic growth rate and the cost of fishing would increase the community’s effective discount rate and consequently result in a much lower equilibrium stock and harvest relative to the situation where the community only use nets with the legal mesh size. Furthermore, under a regulated open access management the equilibrium stock will be lower if a community violates the regulation and the proportionate change in the risk of punishment is higher than the proportionate change in the harvest potential. Moreover, the optimum penalty for violation must be set higher in the open access fishery relative to the complete territorial use right management regime.