They prefer areas with soft substrate, an abundance of aquatic plants and suitable basking sites. Turtles found in the southern ranges are active year around, but turtles found farther north must hibernate in the winter. Daily behavior begins with a morning bask and continues with a mix of foraging and basking. Food preference of the red-eared slider varies with age. Juveniles are highly carnivorous, but as they grow older, eat more vegetable matter.
Adults are omnivorous, eating various aquatic plants and animals.
At the zoo they are fed trout chow, fish and commercial turtle food. Courtship and mating occur in both the spring and fall. Females lay several clutches of 2 to 25 oval shaped eggs each season. Hatchlings are round and are more brightly colored than adults.