About Emys orbicularis (Linnaeus, 1758)
The European pond turtle, scientifically named Emys orbicularis (Linnaeus, 1758), is a medium-sized turtle. Straight carapace length ranges from 12 to 38 cm (4.7 to 15.0 in), with considerable variation across the species' geographic range. Its carapace is dark brown to blackish with a faint green tinge, the head and legs bear yellow spots, and the plastron is yellowish. Temperature and thermal conditions are key factors influencing the development of E. orbicularis. Reportedly, different temperatures across regions lead to varying growth rates for the species, including differences in both body size and clutch size. E. orbicularis displays clear sexual dimorphism: adult males are always smaller than adult females. Males have smaller plastra that give them wider mobility compared to females. For females, differences in diet and foraging habits may be correlated with adaptive changes to their skull and head morphology. This species occurs in southern, central, and eastern Europe, West Asia, and parts of Mediterranean North Africa. In France, only six remaining large populations exist, and these populations are currently declining; the European pond turtle is the most endangered reptile in the country. In Switzerland, the species went extinct at the start of the twentieth century, and was reintroduced there in 2010. During the early post-glacial period, the European pond turtle had a far wider distribution, reaching as far north as southern Sweden and Great Britain. A reintroduction to Great Britain has been proposed by Staffordshire-based organization Celtic Reptile & Amphibian, which specializes in the care, research, and rehabilitation of native European and British herpetofauna. A trial reintroduction has already been launched to restore the species to its original Holocene range in the East Anglian Fens, Brecks and Broads. In 2004, the European pond turtle was discovered in the Setomaa region of Estonia. Fossil evidence confirms that E. orbicularis and Testudo hermanni both lived on Sardinia during the Pleistocene, but molecular data indicates the modern existing populations of both species on the island were introduced in recent times. E. orbicularis prefers to inhabit wetlands surrounded by abundant, lush wooded landscape, and also feeds in upland environments. It is generally considered only semi-aquatic, similar to American box turtles, because its terrestrial movements can cover 1 km (0.62 mi), and it is occasionally found traveling up to 4 km (2.5 mi) from a water source.
