Red-eared slider
Trachemys scripta elegans
The red-eared slider is a medium-sized freshwater turtle belonging to the family Emydidae. It is characterized by its flat, olive-green to dark brown carapace and distinctive red longitudinal stripes behind the eyes. Native to the Mississippi Valley, it has spread globally as an invasive species due to the pet trade. It is a highly adaptable species that prefers stagnant or slow-moving waters with abundant vegetation and basking sites.
Details
Identification
Red patches behind the eyes, yellow stripes on head and limbs, flat carapace with dark spots on marginal scutes.
Social behavior
Solitary, though they often congregate at basking sites without true social bonds.
Diet
Juveniles are predominantly carnivorous (insects, larvae, small fish), while adults increasingly consume aquatic plants and algae.
Hunting strategy
Active hunting of prey in the water as well as grazing on vegetation.
Spawning substrate
Sunny, sandy, or loose soil sites near the water's edge.
Overwintering
Brumation at the bottom of water bodies or buried in mud.
Ecology
Ecological role
Predator of invertebrates and small vertebrates, competitor for native turtle species such as the European pond turtle.
Natural predators
Raccoons, foxes, larger birds (especially for eggs and hatchlings); adults have few natural predators.
Competitor species
Emys orbicularis (European pond turtle)
Ecosystem service
Low; helps control insect populations but often disrupts local ecosystems.
Threats
Habitat loss in their native range; globally more of a threat than threatened.
Scientific profile
Profile
Distinguishing features
Characteristic red postorbital stripe; yellow stripes on head and limbs; posterior margin of the carapace is slightly serrated; strong claws (especially in males).
Habitat
Prefers stagnant or slow-moving waters with soft muddy bottoms, abundant aquatic vegetation, and numerous basking sites. In Europe, frequently found in urban park ponds, lakes, and oxbows.
Diet
Omnivorous; juveniles are predominantly carnivorous (insects, larvae, tadpoles, small fish, crustaceans). With increasing age, the proportion of plant-based food increases (aquatic plants, algae).
Role in food web
Invasive species in Europe; competes with the native Emys orbicularis for basking sites and food. Predates on amphibians and invertebrates. Eggs and juveniles are preyed upon by raccoons, foxes, or herons.
Protection & threats
Main threats
Not threatened in Europe, but rather a threat to biodiversity itself (invasive species). In its native range (USA), locally under pressure due to habitat loss and pollution.
Population trend
In Europe, stable to increasing due to illegal releases, although trade has been strictly regulated since 1997 (EU-wide) and by the Union List (2016).
Conservation measures
Classified in the EU as an invasive alien species of Union concern (Regulation (EU) No 1143/2014). Measures include trade bans, possession bans (with exceptions for existing stock), and removal from the wild to support native species.