River cooters are commonly sold as pets along with other aquatics, i.e. red-ear sliders and map turtles. Hardy, and easy to keep as juveniles, these turtles become too large for most home aquariums. The pictured animal is 28 years old and has a straight line carapace length of 11".
The genus Pseudemys includes several species of cooters and red-bellied turtles. Pseudemys concinna is the species known as the River Cooter. The name "cooter" may have come from an African word "kuta" which means "turtle.
This adult female river cooter is a captive individual. The muted colors of the carapacial design are not usually visible in wild specimens as they would be obscured by mud and algae. Photo by Mary Hopson.
The river cooter is a large (12-16" carapace) freshwater turtle. The carapace is rather flat, not highly domed. It is brown or olive with yellow/cream markings, which vary according to subspecies. The second pleural scute has a characteristic C-shaped mark. Older males may become very dark (melanistic) obscuring much of the carapacial design. Hatchlings have a central keel which disappears with age. The skin is olive to brown, with yellow stripes. Wide, sometimes dark-edged, stripes under the chin form an upside-down "Y." The plastron is yellow and is marked with a large, darker pattern, at least anteriorly. The plastral pattern tends to fade with age. Males have a broader tail and may have a slightly concave plastron. Females tend to grow larger than males.
Ernst, Lovich and Barbour (1994) lists five geographically based subspecies.
In The Wild
River cooters live in a wide variety of freshwater and even brackish locations. Rivers, lakes, ponds and marshes with heavy vegetation provide ideal habitat. Large webbed feet make the river cooter an excellent swimmer, capable of negotiating moderately strong river currents of major river systems. They will collect in large numbers on peninsular floodplains associated with a river oxbow.
In captivity, cooters need an aquatic habitat, with a dry basking area. They need a warming light and UVB radiation (from reptile lights or direct sunshine). As juveniles, they can be kept in a 20- or 30-gallon long tank, but they will outgrow those accommodations, and need a very large tank or outdoor pond.
River cooters enjoy basking on logs or sun-warmed rocks, and are frequently found in the company of other aquatic basking turtles (sliders and painteds) sometimes piled up on top of each other. All are quick to slip into the water if disturbed. Diurnal by nature, these turtles wake with the warming sun to bask and forage. They can move with surprising speed in the water and on land. It is not unusual for them to wander from one body of fresh water to another, but many seem to develope fairly large home ranges, which they seldom or never leave. They sleep in the water, hidden under vegetation. While those that live in areas that are quite warm remain active all winter, river cooters in cooler climes can become dormant during the winter for up to two months, in the mud, underwater. They do not breathe during this time of low metabolism, but can utilize oxygen from the water, which they take in through the cloaca. River cooters perfer to be well hidden under aquatic plants during the winter dormancy period or while sleeping each night.
As with the other basking turtles, the males tend to be smaller than females. Males sport long straight claws which are used as part of the mating dance. After detecting what may be a pheromone signal while sniffing at a female's tail, a male river cooter will court a female by swimming above her, vibrating his long nails and stroking her face. Females have also been observed doing this to initiate courtship. If the female is receptive, she will sink to the bottom of the river and allow the male to mount for mating.
Mating takes place in early spring. Nesting usually occurs from May to June. The female chooses a site with sandy or loamy soil, within 100' of the river's edge. She looks for a rather open area, with no major obstacles for the future hatchings to negotiate on their way to the river. The nest is dug with the hind feet. She lays 10 - 25 or more eggs in one or more clutches. Eggs are ellipsoidal, approximately 1 1/2" long. Incubation time is determined by temperature, but averages 90 - 100 days. Hatchlings generally immerge in August or September. There have been reported instances of late clutches over-wintering and hatching in the spring. A hatchling will have a round carapace, about 1 1/2" diameter, that is green with bright yellow markings.
|The adult female river cooter pictured above laid this egg February 1998, in spite of being indoors for the winter.|
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