The Mediterranean Basin is a heavily pressured World biodiversity hotspot. Mediterranean coastal areas are especially threatened due to tourism, inland migration and population growth, jeopardizing the remaining natural habitats. Protected areas (PAs) aim to conserve biodiversity and ecosystem services in the long term. Here, we assessed whether coastal PAs in 16 Mediterranean countries had been effective at conserving natural habitats from land development between 2000 and 2020, using a Before-After-Control-Impact design with covariates and case-control matching in R. Mediterranean coastal PAs were effective in reducing land development, with just one exception: Israel. Legally stringent reserves were generally more effective than legally lenient multiple-use PAs, with few exceptions: Albania, France and Cyprus. In a number of countries, reserves completely prevented coastal land development, which shows that reserves are a useful tool to preserve waning Mediterranean coastal habitats. Institutional, social, economic and geographic explanatory factors were analysed for PA effectiveness at country scale, but no significant results were found, suggesting high specificity of PA effectiveness.
