Non-Native Turtles (Chelydridae) in Freshwater Ecosystems in Italy: A Threat to Biodiversity and Human Health?

SIMPLE SUMMARY: Marketed globally, freshwater turtles are popular pets. However, the introduction of non-native species can pose a serious threat to biodiversity as well as to human health as carriers of potentially zoonotic pathogens. This update reports the distribution of two species of the Chelydridae family, i.e., the snapping turtle (Chelydra serpentina) and the alligator snapping turtle (Macrochelys temminckii). Their potential impact on human health and biodiversity is also discussed. ABSTRACT: Marketed globally, freshwater turtles are popular pets. Two species of the Chelydridae family are increasingly reported in Italy: the snapping turtle (Chelydra serpentina) and the alligator snapping turtle (Macrochelys temminckii). Both pose potential threats to public safety and habitat biodiversity. This update reports on their distribution and impact on biodiversity and human health. The recent increase in the number of C. serpentina in urban and rural areas suggests illegal importation into the country. Findings are reported for the north (35% and 100% for C. serpentina and M. temminckii, respectively) and the central-northern regions (60% for C. serpentina), predominantly Umbria and Latium, and the Tiber River catchment area in particular. Because omnivorous, Chelydridae species can affect native biodiversity; because they are carriers of pathogens, they endanger public health. Monitoring plans need to take account of this neglected threat.