Can community-protected areas conserve biodiversity in human-modified tropical landscapes? The case of terrestrial mammals in southern Mexico.

Scientists debate two alternative paradigms for tropical biodiversity conservation in human-modified landscapes (HML). Strict government-managed reserves (GMR) have many limitations, including little social support as they transfer conservation costs to local communities. Community-protected areas (CPA) retain control and benefits of biodiversity for local residents, but evidence of their ability to conserve biodiversity is scarce. To test the hypothesis that CPAs are effective in conserving biodiversity, we used camera-trap data to assess differences in abundance, taxonomic and functional (body size and trophic guild) diversity and composition of terrestrial mammal assemblages among CPAs, GMR, and open-access forests (OAF). CPA and OAF sites were located in a HML adjacent to Montes Azules Biosphere Reserve, which is representative of GMR. CPAs and OAFs did not differ in landscape context (forest cover, distance to towns and roads, patch size). Our results show that the HML retains all of the species in the regional pool. We found no difference in species diversity among protection conditions, but species composition was different among them. Abundance of medium-sized generalist species was higher in the HML than in GMR, while large species and small herbivores were scarcer. Abundance of omnivorous and insectivorous generalists was highest in OAF, where large predators were not detected. OAFs exhibited fewer functional groups. No evidence was found that landscape context affected these results. We conclude that CPAs can play an important role in biodiversity conservation. Spatial integration of conservation initiatives and training communities in wildlife management would increase the effectiveness of CPAs.