Local human activities limit marine protection efficacy on Caribbean coral reefs

Marine ecosystems globally have suffered habitat, biodiversity and function loss in response to human activity. Marine Protected Areas (MPAs) can limit extractive activities and enhance ecosystem resilience, but do not directly address external stressors. We surveyed 48 sites within seven MPAs and nearby unprotected areas to evaluate drivers of coral reef condition in the Mexican Caribbean. We found that local human activity limits protection effectiveness. Coral cover was positively related to protection characteristics, but was significantly lower at sites with elevated local human activity. Furthermore, we predict ongoing coastal development will reduce coral cover despite expanded protection within a regionwide MPA if an effective integrated coastal zone management strategy is not implemented. Policy makers must acknowledge the detrimental impact of uncontrolled coastal development and apply stringent construction and wastewater regulations in addition to marine protection.