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The European pond turtle (Emys orbicularis), also called commonly the European pond terrapin and the European pond tortoise, is a species of long-living freshwater turtle in the family Emydidae.

The subspecific name fritzjuergenobsti is in honor of German herpetologist Fritz Jürgen Obst (1939–2018). In the early post-glacial period, the European pond turtle had a much wider distribution, being found as far north as southern Sweden and Great Britain, where a reintroduction has been proposed by the Staffordshire-based Celtic Reptile & Amphibian, a group specialising in the care, research, and rehabilitation of native European and British herpetiles. A trial reintroduction has been initiated, restoring the species back to its Holocene-native East Anglian Fens, Brecks and Broads. In 2004, the European pond turtle was found in the Setomaa region of Estonia.

Fossil evidence shows that E. orbicularis and Testudo hermanni were both present in Sardinia during the Pleistocene, but molecular evidence suggests the extant populations of both species on the island were introduced in modern times.

thumb|A group of European pond turtles in the remnants of the Roman baths in [[Butrint, Albania]]

E. orbicularis prefers to live in wetlands that are surrounded by an abundance of lush, wooded landscape. They also feed in upland environments. They are usually considered to be only semi-aquatic (similar to American box turtles), as their terrestrial movements can span . They are, occasionally, found travelling up to away from a source of water. Due to evident patterns of sexual dimorphism, E. orbicularis adult males are always found to be smaller than females. In males, smaller plastra offer them a wider mobility compared to females. In females, due to their differential diet and foraging habits, there may be a correlation to an adaptive effect on their skull and head morphology. The search for nesting areas, by adult females, can last several hours to several days. Once an appropriate site is found, females take their time with the construction of the nest, painstakingly excavating a small pit out of the soft substrate purely by usage of her small forelimbs. Once satisfied with the depth of the nest, she will turn around (facing away from the nest) and proceed with egg-laying, gently dropping the eggs down and into a small pile. This process varies in duration; laying can take merely half an hour or upwards of several hours, depending on weather, interference by other animals, humans, etc. When laying is complete (and still facing away from the nest), the female turtle will use her back limbs this time, to cover and close the nest. This is another variable routine which can take up to another four hours.

Nest fidelity is a characteristic that is unique to female European pond turtles—selecting a nesting site based on its ecological characteristics—and then returning there for future laying, so long as the site has not changed. The usual life span of E. orbicularis is 40–60 years. It can live over 100 years, but such longevity is rare.

Hatchlings and eggs are preyed upon by various animals including: herons, raccoons, bears (Ursus), kingsnakes (Lampropeltis), ghost crabs, hermit crabs, domestic dogs, gulls (Laridae), alligators (Alligatoridae), crocodiles (Crocodylidae), foxes (Canidae), rats (Rattus), cats (Felis), and cormorants. Young turtles are at risk of becoming prey to predacious fish species as well. Adult European pond turtles are subject to attack by wild dogs, coyotes, carnivorous birds, and humans.

Parasites

E. orbicularis hosts several species of parasites, including Haemogregarina stepanovi, monogeneans of the genus Polystomoides, vascular trematodes of the genus Spirhapalum, and many nematode species.

Human impact

Historically, E. orbicularis had been maintained as pets; however, this practice has been restricted due to protection laws. Ownership of wild caught specimens is prohibited. Only registered captive bred specimens may be owned by private individuals. Due to human impact, the European pond turtle has been found to be relocated in areas distant from its origin. However, it is possible to localize and indicate a region of origin with genetic testing.

The population of E. orbicularis in Ukraine is listed under Appendix III of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

See also

  • List of reptiles of Europe

References

Further reading

  • Arnold EN, Burton JA (1978). A Field Guide to the Reptiles and Amphibians of Britain and Europe. (With 351 illustrations, 257 in colour by D.W. Ovenden). London: Collins. 272 pp. + Plates 1-40. . (Emys orbicularis, p. 93 + Plate 14, figure 1 + Map 48).
  • Boulenger GA (1889). Catalogue of the Chelonians, Rhynchocephalians, and Crocodiles in the British Museum (Natural History). New Edition. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). x + 311 pp. + Plates I-III. (Emys orbicularis, pp. 112–114).
  • Linnaeus C (1758). Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio Decima, Reformata. Stockholm: L. Salvius. 824 pp. (Testudo orbicularis, new species, p. 198). (in Latin).
  • Emys orbicularis
  • ARKive - images and movies of the European pond turtle (Emys orbicularis)
  • Emys orbicularis in The Reptile Database
  • http://politiken.dk/indland/ECE36862/gaaden-om-de-danske-sumpskildpadder/