More amphibians than expected in highway stormwater ponds
Résumé
Some structures developed for particular technical anthropogenic uses are colonized by biodiversity, but
their potential roles have not been seriously considered. Here, we examined whether and how highway
stormwater retention ponds are colonized by amphibians and are used as reproduction sites in humandominated
landscapes.
We addressed their role as habitats for amphibians by sampling amphibians in highway ponds (n = 58)
and in surrounding non-highway ponds (n = 45) and comparing the species richness and the amphibian
abundance using occupancy models that take detectability into account.
As expected, highway ponds differed in abiotic conditions from surrounding ponds. Surprisingly, we
found seven different amphibian species with breeding populations, including one emblematic rare
species (Triturus cristatus), in these artificial ponds. Further, the proportion of the highway ponds where
amphibians were detected was about similar to that of surrounding ponds. Note, however, that the
amphibian abundances were lower in highway ponds.
Surprisingly, our results suggest that highway ponds may contribute in altered landscapes to the biodiversity
of the pond network at a regional scale. Because the adoption of biodiversity-friendly management
measures for these artificial ponds could promote biodiversity in such landscapes, we highlight the most
important factors driving amphibian distribution in these ponds. Due to the importance of these issues,
we stress the need for complementary studies to continue to precisely examine the potential roles of these
ponds as habitats for amphibians and then to propose, if useful, technical pond design and management
recommendations relevant for common biodiversity.