This document describes a study that will experimentally evaluate two interventions aimed at reducing the sale of illegally caught fish during a fishing ban period in Chile: 1) Monitoring and penalizing vendors that sell illegal fish, and 2) Informing consumers about the ban and consequences of overfishing. The study aims to answer questions about the effectiveness of enforcement activities and information campaigns in reducing illegal fish sales, both individually and combined. It also seeks to understand how vendors may adapt their behavior in response to different enforcement strategies. The results could provide insights on regulating common resource exploitation and curbing undesirable behaviors in developing countries.