Trachemys scripta elegans
Reptiles-Turtles
The Slider Turtle (Trachemys scripta) in North America currently is taken to consist of 3 subspecies, T. s, scripta, native to the southeastern US from Virginia to Mexico, T. s, troosti, (Cumberland Slider) with a limited range in western Virginia and eastern Tennessee, and T. s. elegans (Red-eared Slider), with an extensive range in the Mississippi Basin, from West Virginia to Kansas, and Alabama . This turtle ranges form 116 to 294 mm, with males being longer than females. It favors warm-temperate climate but can tolerate cold winters, and summer temperatures up to 40 °C. It prefers freshwater, but tolerates salinity up to 40 PSU. Red-Eared Sliders were extensively harvested in the 19th century and shipped to the East and West Coast as food. In the 20th century, young Red-eared Turtles were extensively shipped to cities for the pet trade. In addition, adult turtles were shipped to schools and college for research and teaching. Some of these animals survived and were released, resulting in many established populations, mostly near urban areas. The pet trade in the US started in the 1920s and mostly ended in 1975, when the Food and Drug Administration banned shipment of turtles less than 4 cm in carapace length, because of risks of Salmonella infection, but juvenile T. scripta continue to be exported to other countries (up to 1-2 million per year). Red-Eared Turtles have been introduced to at teast 31 states and ~51 countries. The IUCN (International Union for the Conservation of Nature) Global Invasive Species Database counts Trachemys scripta elegans among the '100 Worst Inavasive Species).. Global concerns include competition from native turtles, often depleted by harvesting and habitat disturbance, and spread of diseases.
Introduced estuarine populations are known from the San Francisco Bay Delta, the Columbia River estuary, the Delaware River, and Chesapeake Bay, and from the Great Lakes basin. Dates of invasion are difficult to determine, because there are many records of the capture of single animals. Individuals were captured in North Carolina in 1916. and near Lake Michigan in 1924. They were established around Baltimore by 1941, and near Washington DC in 1959. In the San Francisco Bay Delta by 1976, and in the Columiba River estuary by 1994. Established estuarine populations are probably more widespread, given this turtle's wide distirbution.