These turtles also have a complete skeletal system, with partially webbed feet that help them to swim and that can be withdrawn inside the carapace along with the head and tail.

The red-eared slider originated from the area around the Mississippi River and the Gulf of Mexico, in warm climates in the Southeastern United States.

In nature, they inhabit areas with a source of still, warm water, such as ponds, lakes, swamps, creeks, streams, or slow-flowing rivers.

Invasive red-eared sliders cause negative impacts in the ecosystems they are introduced to because they have certain advantages over the native populations, such as a lower age at maturity, higher fecundity rates, and larger body size, which gives them a competitive advantage at basking and nesting sites, as well as when exploiting food resources.

[20] Owing to their popularity as pets, red-eared sliders have been released or escaped into the wild in many parts of the world.

[27] In Australia, it is illegal for members of the public to import, keep, trade, or release red-eared sliders, as they are regarded as an invasive species[28] – see below.

[30] In 2015, Japan announced it was planning to ban the import of red-eared sliders,[31] and officially established in June 2023.

While this bans it and red swamp crayfish from importing, trading and releasing to wild, it is still able to keep it alive at home.

Red-eared sliders do not hibernate, but actually brumate; while they become less active, they do occasionally rise to the surface for food or air.

[11] During this time, the turtles enter a state of sopor, during which they do not eat or defecate, they remain nearly motionless, and the frequency of their breathing falls.

Courtship and mating activities for red-eared sliders usually occur between March and July, and take place under water.

During courtship, the male swims around the female and flutters or vibrates the back side of his long claws on and around her face and head, possibly to direct pheromones towards her.

Young turtles may carry out the courtship dance before they reach sexual maturity at 5 years of age, but they are unable to mate.

This process also permits the laying of fertile eggs the following season, as the sperm can remain viable and available in the female's body in the absence of mating.

During the last weeks of gestation, the female spends less time in the water and smells and scratches at the ground, indicating she is searching for a suitable place to lay her eggs.

Damage to or inordinate motion of the protruding egg yolk – enough to allow air into the turtle's body – results in death.

If it manages to reach term, the turtle will try to flip over with the yolk sac, which would allow air into the body cavity and cause death.

[43] Reptiles are asymptomatic (meaning they suffer no adverse side effects) carriers of bacteria of the genus Salmonella.

[45] This has given rise to justifiable concerns given the many instances of infection of humans caused by the handling of turtles,[46] which has led to restrictions in the sale of red-eared sliders in the United States.

A fine up to $1,001 and / or imprisonment for up to one year is the penalty for those who refuse to comply with a valid final demand for destruction of such turtles or their eggs.

Small children must be taught to wash their hands immediately after they finish playing with the turtle, feeding it, or changing its water.

Some states have other laws and regulations regarding possession of red-eared sliders because they can be an invasive species where they are not native and have been introduced through the pet trade.

However, unusual color varieties such as albino and pastel red-eared sliders, which are derived from captive breeding, are still allowed for sale.

[52] Because red-eared slider turtles eat plants as well as animals, they could also have a negative impact on a range of native aquatic species, including rare frogs.

[53] Also, a significant risk exists that red-eared slider turtles can transfer diseases and parasites to native reptile species.

[50] The turtle may also cause significant public-health costs due to the impacts of turtle-associated salmonella on human health.

[57] Experts have ranked the species as high priority for management in Australia, and are calling for a national prevention and eradication strategy, including a concerted education and compliance program to stop the illegal trade, possession, and release of slider turtles.

[60] Between August 2018 and June 2019, a team of herpetologists from the NGO "Help Earth" found red-eared sliders in the Deepor Beel wildlife sanctuary and Ugratara Devalaya temple pond.

[61] Further reports have been made from an unnamed stream, feeding into the Tlawng river, on a farm in the Mizoram capital, Aizawl.

[citation needed] Within the second volume of the Tales of the Teenage Mutant Ninja Turtles, the popular comic-book heroes were revealed as specimens of the red-eared slider.