Screening for Batrachochytrium salamandrivorans in a population of Golden Alpine Salamanders at the edge of their distribution range

Abstract

Amphibian populations worldwide are experiencing significant declines, highlighting a critical aspect of the broader biodiversity crisis. Approximately 43% of all amphibian species are facing extinction due to factors such as habitat loss, pollution, climate change, and emerging diseases. The chytrid fungus Batrachochytrium salamandrivorans (Bsal) represents one of the major threats, because it is particularly dangerous for European salamanders. Southern Europe is especially vulnerable due to the presence of numerous endemic salamander species. Despite the risks, few studies have screened Italian salamanders for Bsal. We conducted a Bsal screening on 44 Golden Alpine Salamanders (Salamandra atra aurorae) from the Vezzena plateau in the Trentino-Alto Adige region (Northern Italy). Our molecular analysis of skin swabs revealed no presence of Bsal in any of the 44 specimens examined. Additionally, no macroscopic signs of Bsal-related skin damage were observed. The absence of Bsal in our samples is encouraging, suggesting that the investigated sites are currently unaffected by this pathogen. This finding aligns with other studies reporting no evidence of Bsal in Italy. Future research should explore the factors contributing to the absence of Bsal and the effectiveness of current conservation practices. While our findings are reassuring, the threat of Bsal remains a critical concern. Continued vigilance and enhanced conservation efforts are essential to protect salamander diversity and ensure the long-term survival of these important amphibian populations.