Applying niche-based models to predict endangered-hylid potential distributions: are neotropical protected areas effective enough?

Tropical amphibians face a severe decline crisis with ca. 35% of species being currently threatened in the Neotropics. We selected 16 endangered-hylid species and used species records to model their potential geographical distribution for the continental Neotropics. We found that there is a strong influence of slope in hylid geographical distribution that interacts synergistically with maximum rainfall and temperature changes over the year. We identified some intersecting areas of species overprediction along southern Neotropics, which could be important for future biological surveys searching for undescribed microendemic hylid species. Nine of the 16 studied hylids have small geographic ranges with only 25% of its potential distribution being currently protected in the Neotropics. The remaining seven species are still in need of additional conservation areas to ensure the protection of at least 25% of its original distribution range in Mesoamerica. Most Neotropical endangered hylids have only the periphery of their distribution protected with its core distribution outside protected areas. These species may be especially threatened because they now occur in small, isolated subpopulations due to habitat fragmentation and loss. We suggest that conservation efforts for Neotropical hylids should be focused on restricted-range species and in the establishment of additional conservation area networks in Mesoamerica. Remaining habitats for threatened hylids need to be managed as a coordinate network including site-scale and landscape-scale actions to buffer the extinction-driven process caused by inbreeding, genetic drift, and demographic stochasticity.