Overfishing has become a major global issue that endangers ecosystems and the livelihoods of millions of people. Weak enforcement and illicit fishing behaviors limit the effectiveness of institutional arrangements designed to curb overfishing. In this paper, we designed and tested a series of potential interventions to reduce overexploitation driven by illegal fishing. We use surveys, interviews, and common pool resource experiments to investigate the behavior of Mexican fishermen in the upper part of the Gulf of Baja California. We find that resource exploitation can be reduced using a mechanism that regroups fishermen according to their past fishing exploitation levels. More precisely, we observe that the announcement of this mechanism and the actual regrouping reduce common pool exploitation, regardless of group composition. Further experimental evidence shows that the regrouping intervention also achieves the desired outcomes in environments with informational asymmetries or regrouping imperfections.
