Eurasian Pond and River Turtles and Neotropical Wood Turtles: Geoemydidae

Just as the habitat, or the natural living area, differs from species to species in this family, so, too, does their behavior and method of reproduction. Some of them hardly ever leave the water, but others live on land. Many of them are active all year long, but others become inactive during the winter months or during dry spells. Some, such as the Chinese stripe-necked turtle, sunbathe, or "bask," onshore to warm their bodies.

Although scientists know few details about many of these turtles, they have noted that the adult male of some species will bite or bump up against a female to persuade her to mate. Also, the heads and legs of a few species will become more brightly colored during mating season, probably to attract a mate. Male painted terrapins, for example, normally have gray heads, but their heads become white with a red stripe during mating season.

Females of the larger species lay the most eggs—up to thirty-five eggs at a time. The smallest species may lay just a single egg. Female painted terrapins travel as far as 31 miles (50 kilometers) to reach a good nesting site and then lay their eggs at night. They lay eggs about five times a year. In many cases, the temperature of the nest does not affect the sex of the newly hatched young turtles. In other species, however, a particularly warm nest temperature produces all females, and a cool one produces males. In at least one species, the eggs may also become females if the nest temperature is especially cold.

Eggs hatch in sixty to 272 days. In some species, males can become parents when they reach three or four years old, but females must wait until they are five to eight years old. Sometimes two different species of Eurasian pond and river turtles and neotropical wood turtles mate with each other and produce young turtles. This can happen often when two turtles from different species of this family are put together in one aquarium, but it may not happen as often in the wild.