Painted turtles (like all reptiles) are ectothermic, or cold-blooded, and basking in the sun helps them warm up. Also, leeches and algae that attach to them as they swim dry up and fall off, leaving their shells smooth once again. Painted turtles are quick to slip into the water when disturbed, but if you approach quietly and stay far enough away, you may be able to tell males and females apart. Males have long nails, while females have short ones. The male uses his long nails to stroke the female’s head and neck during courtship and to hold onto her shell during mating. The female uses her nails to dig a hole in which to lay her eggs.