The turtle eats aquatic vegetation, algae, and small water creatures including insects, crustaceans, and fish.

[9] Although they are frequently consumed as eggs or hatchlings by rodents, canines, and snakes, the adult turtles' hard shells protect them from most predators.

In modern times, four U.S. states (Colorado, Illinois, Michigan, and Vermont) have named the painted turtle their official reptile.

[12] The subspecies name, marginata, derives from the Latin for "border" and refers to the red markings on the outer (marginal) part of the upper shell; dorsalis is from the Latin for "back", referring to the prominent dorsal stripe; and bellii honors English zoologist Thomas Bell, a collaborator of Charles Darwin.

The western and southern subspecies met in Missouri and hybridized to produce the midland painted turtle, which then moved east and north through the Ohio and Tennessee river basins.

Although this proposal was largely unrecognized at the time due to evidence of hybridization between dorsalis and picta, the Turtle Taxonomy Working Group and the Reptile Database have since followed through with it, although both the subspecific and specific names have been recognized.

Similar to the top shell, the turtle's skin is olive to black, but with red and yellow stripes on its neck, legs, and tail.

Also, the slider has a prominent red marking on the side of its head (the "ear") and a spotted bottom shell, both features missing in the painted turtle.

[29][64][65] There is a harsher divide between midland and eastern painted turtles in the southeast because they are separated by the Appalachian mountains, but the two subspecies tend to mix in the northeast.

Many studies have been performed in the border regions to assess the intermediate turtles, usually by comparing the anatomical features of hybrids that result from intergradation of the classical subspecies.

[31][75][76] In the southeast, the border between the eastern and midland is more sharp as mountain chains separate the subspecies to different drainage basins.

Further west, the rest of Illinois, Wisconsin and the UP are part of the range proper, as are all of Minnesota and Iowa, as well as all of Missouri except a narrow strip in the south.

However, the turtle is confirmed present in the lower elevation southwest part of the state (Archuleta and La Plata counties), where a population ranges into northern New Mexico in the San Juan River basin.

[92] In Utah, the painted turtle lives in an area to the south (Kane County) in streams draining into the Colorado River, although it is disputed if they are native.

[3] To thrive, painted turtles need fresh waters with soft bottoms, basking sites, and aquatic vegetation.

Rivers and large lakes have lower densities because only the shore is desirable habitat; the central, deep waters skew the surface-based estimates.

[109] For older turtles, some attempts have been made to determine age based on size and shape of their shells or legs using mathematical models, but this method is more uncertain.

[117] Although all subspecies of painted turtle eat both plants and animals (in the form of leaves, algae, fish, crustaceans, aquatic insects and carrion), their specific diets vary.

[121] Painted turtles obtain coloration from carotenoids in their natural diet by eating algae and a variety of aquatic plants from their environment.

As adults, the turtles' armored shells protect them from many potential predators, but they still occasionally fall prey to alligators, ospreys, crows, red-shouldered hawks, bald eagles, and especially raccoons.

She presses her throat against the ground of different potential sites, perhaps sensing moisture, warmth, texture, or smell, although her exact motivation is unknown.

[116] Hatchlings north of a line from Nebraska to northern Illinois to New Jersey[137] typically arrange themselves symmetrically[138] in the nest and overwinter to emerge the following spring.

The painted turtle is genetically adapted to survive extended periods of subfreezing temperatures with blood that can remain supercooled and skin that resists penetration from ice crystals in the surrounding ground.

Adaptations of its blood chemistry, brain, heart, and particularly its shell allow the turtle to survive extreme lactic acid buildup while oxygen-deprived.

[150] However, painted turtles can tolerate long periods of anoxia due to three factors: a depressed metabolic rate, large glycogen stores in the liver, and sequestering lactate in the shell and releasing carbonate buffers to the extracellular fluid.

[3] The painted turtle's high reproduction rate and its ability to survive in polluted wetlands and artificially made ponds have allowed it to maintain its range,[46][168] but the post-Columbus settlement of North America has reduced its numbers.

[178] Other factors of concern for the painted turtles include over-collection from the wild,[188] released pets introducing diseases[189] or reducing genetic variability,[187] pollution,[190] boating traffic, angler's hooks (the turtles are noteworthy bait-thieves), wanton shooting, and crushing by agricultural machines or golf course lawnmowers or all-terrain vehicles.

[213][214] Wisconsin formerly had virtually unrestricted trapping of painted turtles but based on qualitative observations forbade all commercial harvesting in 1997.

Nets, hand capture, and fishing with set lines are generally legal, but shooting, chemicals, and explosives are forbidden.

[234] Colorado chose the western painted turtle in 2008, following the efforts of two succeeding years of Jay Biachi's fourth grade classes.