Multiscale drivers of amphibian community occupancy in urban ponds

Urbanization has driven the loss of natural aquatic habitats while concurrently increasing the abundance of artificial urban ponds. Urban ponds are not typically designed for wildlife but are often colonized by species of conservation concern, including amphibians. Urban ponds may have conservation value, but it is unclear whether they are equally suitable habitat for all amphibians within a local assemblage and which factors most affect habitat quality. Here, we surveyed 96 ponds in the greater Madison, Wisconsin area from four land-use types: 1) golf course ponds, 2) urban park ponds, 3) urban stormwater ponds, and 4) ponds within mixed-use exurban regions. We assessed which local pond characteristics and landscape factors influenced occupancy of amphibian communities using a Bayesian multispecies occupancy model. We detected nine species, finding at least one species at most ponds (91.8%). Ponds within golf courses and urban parks had higher naïve species richness than other urban ponds. We grouped species based on their habitat requirements in their adult stage as (1) upland (for terrestrial adults) and (2) fully aquatic. Occupancy of upland species increased with greater forest cover and pond area, while occupancy of fully aquatic species increased with greater wetland cover, water fluorescence, and lower water turbidity. Our results suggest that species habitat preferences influence the urban ponds they occupy. Urban ponds provide important amphibian habitat for varied species assemblages. Strategic management of urban ponds could therefore provide key ecosystem services, while also facilitating the conservation of amphibians that are increasingly threatened by habitat loss.