Potential distribution, observed impacts, and invasion risk of two non-native snapping turtles, Chelydra serpentina and Macrochelys temminckii

Abstract

Among reptiles, turtles are the most frequently traded and introduced species, and are often released in the wild once they become unwanted as pets. The common snapping turtle Chelydra serpentina and the alligator snapping turtle Macrochelys temminckii are freshwater turtles native to North America. Although their trade is regulated in some countries, they have been introduced worldwide as pets. While C. serpentina already has some established self-sustaining populations outside its native range, there are no such reports for M. temminckii. However, there are increasing records from the wild for both species, and a thorough assessment of the potential climatic suitability, observed impacts and invasiveness of these two species has never been performed. Here, we combined Species Distribution Models (SDMs) under current and future climatic scenarios, standardized scoring impact systems (EICAT(+) and SEICAT) and invasiveness risk assessments (AS-ISK). Our results show a wider climatic suitability for C. serpentina outside its native range but no highly suitable areas outside theits native range of for M. temminckii. Our models also revealed a decrease in climatic suitability for both species in their native range under future climate scenarios, raising potential concerns for their conservation. Only C. serpentina could be assessed for its impacts, being attributed a minor impact score. The invasiveness risk assessments attributed a medium risk to C. serpentina and a low risk to M. temminckii. In any case, Our results suggest, anyway, that proper data collection outside both species’ native ranges are necessary to monitor the status of these as alien species.

Authors and Affiliations

• Iacopo Nerozzi - Alma Mater University of Bologna, Bologna, Italy
• Ismael Soto - University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, 389 25 Vodňany, Czech Republic. ORCID: 0000-0002-7288-6336
• Giovanni Vimercati -
• César Capinha -
• Ali Serhan. Tarkan -
• Fred Kraus -
• Phillip J. Haubrock - University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, 389 25 Vodňany, Czech Republic; Department of River Ecology and Conservation, Senckenberg Research Institute and Natural History Museum Frankfurt, Gelnhausen, Germany; CAMB, Center for Applied Mathematics and Bioinformatics, Gulf University for Science and Technology, Kuwait. ORCID: 0000-0003-2154-4341
• Olivier S. G. Pauwels -
• Marco A. L. Zuffi -
• Paride Balzani✝ - University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, 389 25 Vodňany, Czech Republic.

✝Corresponding author: Paride Balzani