The western painted turtle is a small, brightly colored aquatic turtle with a smooth upper shell. The general color of the carapace (upper shell) is olive, olive brown, or nearly black; usually there are irregular yellow lines; the marginal scutes (shell scales) may have one or more yellow bars and a red-orange outer edge. The plastron (lower shell) is yellow orange, bright orange, or red, with a prominent pattern of brown markings. Exposed skin is dark brown or black and is strongly patterned with yellow lines. Lines on the neck and forelimbs can be orange or red.
Similar species: The closest relative in Missouri is the southern painted turtle (Chrysemys dorsalis), but it occurs only in the Bootheel region, where the western painted turtle is not found. The southern painted turtle looks similar, but it has a prominent lengthwise orange, red, or yellow stripe down the upper shell; also, its lower shell is plain yellow.
See "Status" below for a discussion of possible intergrades and subspecies in Missouri.
Less closely related, but still rather similar to painted turtles, are a number of other aquatic or semiaquatic members of the pond and box turtle family. Some of these relatives may occur in the same Missouri regions as the western painted turtle. These include the northern map turtle, Ouachita map turtle, northern false map turtle and Mississippi map turtle, eastern river cooter, and red-eared slider.
Adult upper shell length: 4½ to 8 inches; occasionally to 10 inches. Females are larger than males.
Occurs statewide, excluding the Missouri's extreme southeastern corner. Apparently most abundant in marshlands in the grassland regions of western and northern Missouri.
Habitat and Conservation
This turtle is usually active between early April and October. In Missouri, the western painted turtle occurs in slow-moving rivers, sloughs, oxbow lakes, ponds, drainage ditches, and marshes, especially where there is ample mud and abundant aquatic vegetation. They typically avoid waters with fast-flowing current.
Painted turtles are active by day and sleep during the night in pools or ponds. During the day, they alternately bask and forage in the water. They require objects, such as partly submerged logs, rocks, or mats of aquatic plants, upon which they may climb and bask.
Although this species is mainly aquatic, individuals are seen crossing roads, fields, and yards.
During the cold winter months, adults overwinter in the deeper bottoms of wetlands, usually buried in the mud.
This turtle eats aquatic plants and algae, snails, crayfish, earthworms, leeches, insects, and fish. It will also readily consume carrion. The young reportedly eat more animal material than adults.
Taxonomically, the status of the painted turtle group is somewhat uncertain. Currently, three subspecies of C. picta are recognized, now that the southern painted turtle (formerly considered a subspecies) has been elevated to full species status. Questions still remain about the validity of the three subspecies and about apparent intergrades occurring in Missouri.
There may be small populations of intergrades between the midland painted turtle (C. p. marginata) in a few eastern Missouri counties; also, painted turtles captured in the southeastern part of the Ozarks typically have a weak mid-dorsal stripe compared to C. dorsalis and less intense belly patterns compared to C. p. bellii. Additional studies are needed in these areas to verify these possible intergradations.
Courtship and mating occur in shallow water from April to June, but these activities have also been observed in the fall. Egg-laden females leave the water to search for a suitable place to dig a nest. Ideal nest sites are on gentle, south-facing slopes with loose dirt or sand and some low vegetation. In Missouri, eggs are laid in mid-May through July. There can be 4–23 eggs per clutch (the average is 12), with 2 or 3 clutches per season. Eggs hatch in about 8–11 weeks. Hatchlings stay underground until spring if the eggs were laid late in the summer.
Males become mature at 2–4 years of age; females mature at 6–10 years of age. Lifespan in the wild can be at least 30–40 years.
Painted turtles appear in Native American legends and are beloved by many people. They are often kept as pets in captivity, but a great many of those die due to improper care, including specific food, lighting, water, and heating needs. In some parts of the world, they are an invasive species.
Although the hard shell protects adults from predators, the eggs and young are vulnerable to a wide array of predators.
What explains the bright colors? It turns out that turtles have good color vision, so unique colors and patterns probably help them recognize members of their own species.
The western painted turtle's range extends north into south-central Canada, Wisconsin, and eastern Montana, and in numerous other western states. Surviving long periods of inactivity in these northern climates, where winters can be incredibly cold, can be a challenge for many freshwater turtles. Painted turtles have unique physiological adaptations to survive for extended periods within these cold environments.
- To survive winters, adult painted turtles significantly reduce their metabolic rates. Additionally, as they hibernate under water, they can prevent a deadly lactic acid buildup in their bodies caused by the oxygen-depleted environment. A large amount of lactic acid is transported into the turtle shell, where it is buffered (de-acidified or neutralized) and stored.
- Meanwhile, the hatchlings that overwinter in their rather shallow nests (only to about 5 inches deep) might easily freeze, their body tissues and blood vessels disrupted and split by the formation of ice crystals. But researchers have found that these hatchlings can survive by supercooling to resist actual freezing. Basically, they do not freeze because their tissues can drop below the freezing point without ice crystals forming. This occurs not because their bodies create an antifreeze (such as elevated levels of glucose in the blood to lower its freezing point), but by purging ice-nucleation sites (tiny particles where ice crystals can start to form) from the blood and other liquids in their bodies. Also, the chemistry of their shells and skin prevents any ice that forms around them from causing the fluids in their bodies to freeze.