The National Natural Park "Corales del Rosario y San Bernardo", located in the Caribbean Sea, is one of the most important parks in Colombia since it hosts high biological biodiversity, receives more tourists than any other natural park in the country and provides sustenance to several communities settled in and around it. However, lack of governance and incompatibility of incentives among authorities, communities and visitors threaten its conservation and sustainability. Using experimental economic games with fisherman communities, we tested different rules related with the management of natural resources in the protected area. In addition to standard rules of communication and external regulation, we tested a rule called co-management, in which we explored the complementarities between repeated communication and external non-coercive authority intervention. We also tested inter temporal effects where over extraction (by the group) in a round reduces the availability of resource for next round and, in consequence, increases effort and reduces benefits for fishers. Results confirmed the effectiveness of communication and, to some extent, external regulation. More important than that, co-management treatment exhibit no matter the location of the communities with respect to the park- the best results in terms of sustainable use of the resource. Participants incorporated dynamic implications in their decisions when information asymmetries were overcome, through internal communication or external guidance. These results highlight the importance of resource management designs that recognize communities as key actors in decision making for the sustainable use and conservation of common pool resources in protected areas.