How much can highway stormwater ponds contribute to amphibian ecological network connectivity?

ABSTRACT Several studies assert that transportation infrastructure rights-of-way can play a positive role for many animal species, especially in highly fragmented and human-dominated landscapes. This study examines the contribution of highway stormwater ponds to amphibian ecological networks, questioning both the influence of their location on species richness and their capacity to increase landscape connectivity. The ecological networks of amphibian species were modeled by graph theory around highway A77 (France). Stormwater ponds as well as natural ponds were included as potential habitats and several connectivity metrics were calculated at different scales. The connectivity values of the stormwater ponds were analyzed in relation to species presence data collected in 2018. While most of these ponds contribute little to regional connectivity, some of them represent important connector patches. Statistical analysis also suggests that highway ponds are used by amphibians in areas with few natural pools. This raises questions about how to improve the management of ecological networks by considering the capacity of artificial habitats to serve as a refuge for biodiversity.