Monsters In The City: Multiple Deformities Increase In Terrestrial-Breeding Urban Salamanders

Amphibians are subjected to an assortment of environmental stressors responsible for their population declines and malformations. Deciphering the underlying causes of amphibian deformities is challenging due to the complex nature and interplay among factors. We evaluated morphological deformities in 9 urban and 9 woodland populations of terrestrial breeding fire salamanders. We report several types of malformations and higher incidences among urban populations. This model system allowed us to tease apart some of the common factors responsible for amphibian deformations, suggesting airborne/terrestrial pollutants, predation, and/or inbreeding as potential environmental stressors. Yet, the putative underlying factors of fire salamander deformities need to be properly addressed in thorough studies linking habitat quality and the prevalence of morphological abnormalities, as well as predator-prey interactions. Reporting deformation rates among amphibians is key to identify warning signals of population declines and preventing local extinctions.