Rapid conservation assessment for endangered species using habitat connectivity models

To avoid extinction of rare species in regions of active environmental change, strategic approaches are needed to manage remaining habitat. When observations of dispersal or metapopulation information are not available, habitat connectivity simulations may offer a valuable alternative source of information to assess threats and evaluate conservation options. For the Critically Endangered San Martin titi monkey (Callicebus oenanthe) in north central Peru, an updated distribution model was generated and land cover in the heavily deforested northern range of the species was mapped. The value of remaining forest fragments was characterized and threats from future land use change were assessed using complementary connectivity models. It is estimated that the species range is less than 14 000 km². Remote sensing analysis reveals that at least 34% of lowland forest in the northern range has been lost, while nearly 95% of remaining habitat fragments are likely too small to support viable populations and less than 8% of this habitat lies within conservation areas. Areas with the highest modelled connectivity comprise only 10% of the remaining forest in the northern range and small patches may contribute disproportionately to movement; these lands represent opportunities for conservation and reforestation to prevent potentially significant impacts from future mining and urban development. This study prioritized remaining suitable habitat patches using modelled connectivity and local knowledge to gain insight into the status of an understudied species. This approach offers a relatively rapid method to identify potential land use conflicts, and to further focus research and locally appropriate conservation.