Effect of land use, habitat suitability, and hurricanes on the population connectivity of an endemic insular bat

Habitat loss and fragmentation are a leading cause of vertebrate population declines and extinction. Urbanization and natural disasters disrupt landscape connectivity, effectively isolating populations and increasing the risk of local extirpation particularly in island systems. Puerto Rico, one of the most isolated islands in the Caribbean, is home to 13 bat species that have been differentially affected by disturbance during the Anthropocene. We used circuit theory to model the landscape connectivity within Puerto Rico with the goal of understanding how fragmentation affects corridors among forested areas. Models combined species occurrences, land use, habitat suitability, and vegetation cover data to examine connectivity in the endemic bat Stenoderma rufum, and also at the bat community level across the island. Urbanization in Puerto Rico affected bat connectivity overall from east to west and underscored protected and rustic areas for the maintenance of forest corridors. Suitable habitat provided a reliable measure of connectivity among potential movement corridors that connected more isolated areas. We found that intense hurricanes can disrupt forest integrity and affect connectivity of suitable habitat. Some of the largest protected areas in the east of Puerto Rico are at an increasing risk of becoming disconnected from more continuous forest patches. The disruption of corridors that maintain connectivity on the island could explain previous findings of the slow post-hurricane population recovery of S. rufum. Given the increasing rate of urbanization, this pattern could also apply to other vertebrates not analyzed in this study. Our findings show the importance of maintaining forest integrity, emphasizing the considerable conservation value of rustic areas for the preservation of local biodiversity.