European Pond Turtles' Future at Risk: Researchers Reveal the Biggest Threat

Researchers from the HUN-REN Balaton Limnological Research Institute, the Hungarian University of Agriculture and Life Sciences, and the University of Pécs have studied the threats to the European pond turtle (Emys orbicularis) for two years, following repeated discoveries of depredated turtle nests by conservationists and researchers in the southern regions of Kis-Balaton and Lake Balaton. To evaluate the severity of the problem, they used clay eggs placed in artificial nests and clay models imitating hatching turtles. Bite and beak marks on the clay eggs revealed the predators' identities.

The research shows that red foxes are the main cause of egg losses, while newly hatched turtles are attacked by red foxes, corvids, and wild boars.

According to the researchers, it is surprising that survival was worst in the least disturbed Kis-Balaton compared to the more disturbed marshes around Lake Balaton, such as Nagyberek near Fonyód and Ordacsehi-berek. Most of the artificial nests were depredated by predators, although the hatchlings had slightly better chances of survival. However, the limited availability of terrestrial nesting sites and their distance from water were also found to further increase losses. The researchers warn that without targeted conservation efforts—such as predator control and habitat protection—the situation for European pond turtles could worsen further.

More details can be found on the website of the HUN-REN Balaton Limnological Research Institute.