Institutional legacies explain the comparative efficacy of protected areas: Evidence from the Calakmul and Maya Biosphere Reserves of Mexico and Guatemala

•Differential effectiveness of protected areas is the result of preexisting political and economic conditions.•Protected areas which have greater levels of economic and political equality may be more effective at nature conservation.•Developing effective conservation plans requires understanding the historical development of local political institutions. The effectiveness of protected areas at achieving nature conservation goals varies widely, but the reasons for this variation are understudied. We argue that an important, but often neglected, factor is the history of institutional development that pre-dates protected area establishment. Through a comparative analysis of pathways of institutional development in Calakmul and Maya Biosphere Reserves, internationally adjoining protected areas in Mexico and Guatemala, we demonstrate that differences in farmer and community-level conservation behavior between the two reserves are the result of differences in land tenure systems that pre-date reserve establishment. Differences in land tenure systems resulted in a lower population density, greater tenure security, and greater economic and political equality in the Calakmul Biosphere Reserve. All of these factors influenced farmers and communities in the Calakmul Biosphere Reserve to have more favorable attitudes towards conservation, conserve more forest on both individual and community managed land, and to create more conservation reserves on both land types. These differences are rooted in the system of land distribution and political organization during the 1970s and 1980s, before protected area establishment, when both areas were agricultural frontiers. As a result of these political processes that pre-date reserve creation, farmers and communities in Calakmul hold more land and hold it more equitably, have less access to surplus labor for expanding commercial production, and have a political system that shares benefits from forest conservation more equitably when compared to Maya. Our work highlights the value of understanding historical political and institutional conditions in the design and development of effective protected areas. Protected areas located in areas with greater economic and political equality may be more effective at conserving nature.