Distribution and Potential Limiting Factors of the European Pond Turtle (Emys orbicularis) in Eastern Europe

Oksana Nekrasova,Andris Čeirāns,Mihails Pupins,Arturs Skute,Oleksii Marushchak,Volodymyr Tytar

doi:10.3390/d13070280

Abstract

In order to use an integrated approach for studying the influence of risk factors on the distribution of the native turtle species E. orbicularis and accompanying invasive species (T. scripta and N. procyonoides) in the northeast of their range, we used GIS modelling and a database (GAEZ, human footprint, CliMond) of 55 preselected variables, which represent a system of bioclimatic and anthropogenic factors. The main variables that influenced the results were factors related to temperature. There was a high correlation (r = 0.6) between the species distribution model’s habitat suitability for E. orbicularis and the corresponding “human footprint” values within the European part of the species’ natural range. Its unpretentiousness towards anthropogenic factors would likely help the further expansion of its range in eastern Europe, because the areas with the highest habitat suitability (r > 0.7) were projected to increase 3.3-fold. When comparing the E. orbicularis model to those obtained for N. procyonoides and T. scripta, we concluded that N. procyonoides could be dangerous because it occupies similar habitats (the degree of correlation is reasonably high in the north of their range (r = 0.5) in Latvia). An expansion of the range of Trachemys scripta is also possible in the future within the northern territories. Therefore, when developing the turtles’ protection algorithms, it is also necessary to take into account the influence of invasive species.

Highlights

It is evident that the environment is changing under the influence of anthropogenic pressure and climatic changes, including the habitats of autochthonous species of animals
E. orbicularis is listed in Resolution No 6 of the Bern Convention (1979) Emys orbicularis (1220), which means that this species requires the development of Emerald Network sites in the territories it inhabits for its protection [21]
Nyctereutes procyonoides occupies a wide range of territories in Polissia and the forest-steppe zone, preferring wet meadows with swampy lowlands, overgrown river floodplains and riverine forests with dense undergrowth; Nyctereutes procyonoides is unpretentious when choosing places to inhabit

Summary

Introduction

It is evident that the environment is changing under the influence of anthropogenic pressure and climatic changes, including the habitats of autochthonous species of animals. Nyctereutes procyonoides occupies a wide range of territories in Polissia (forested biogeographical region which starts from the farthest edge of central Europe and encompasses eastern Europe, including eastern Poland, the Belarus–Ukraine border and western Russia) and the forest-steppe zone, preferring wet meadows with swampy lowlands, overgrown river floodplains and riverine forests with dense undergrowth; Nyctereutes procyonoides is unpretentious when choosing places to inhabit It is quite often spotted in territories with light soils, and sometimes near arid areas along small waterbodies, which is where the turtles breed [28]. We hypothesized that, despite climate change and the possibility of the turtle’s (E. orbicularis) “shift” to the north, anthropogenic influences and newly emerging biotic components of ecosystems (invasive species (predators and competitors)) may be important risk factors to consider

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Results