Non-native common snapping turtle Chelydra serpentina (Linnaeus, 1758) in Western Europe: a focus on Central Italy showing evidence of a hot spot of introduction

Abstract

The common snapping turtle, Chelydra serpentina (Linnaeus, 1758), is a robust aquatic turtle native to southeast North America. However, it has also been introduced to other countries through the exotic pet trade, where it has gained popularity due to its distinctive appearance and impressive size. Over the past decade, a considerable number of individuals, abandoned by their owners, have been recorded and captured in Western Europe. Here, we report the first comprehensive summary of records at continental scale, showing that France and Italy represent the countries with the highest number of sightings. In France, exhibition, exchange, or sale events of exotic animals (until 2022 legal; now illegal) have been located near large cities, although records of C. serpentina were significantly higher outside the core of urban areas. We also recorded a significant increase in total number of records at European scale when comparing the periods of 2010-2015 and 2016-2020. Finally, we focused the current study on a peculiar spatial pattern at local scale (Central Italy) near an important site of exhibition and sale events of exotic animals, suggesting the presence of a hot spot of introduction. Popular events may represent critical colonization hubs from where these freshwater turtles can disperse into the surroundings.