Instructions
Examine the boney plates (called scutes) that make up the turtle shell. These look like large rectangular or rounded scales. As the turtle grows, it sheds the outer layer of the scute to reveal a new plate.
Look for distinct rings that surround the scute. These may be lighter in color and look similar to the rings seen in trees. According to the Lee and Rose Warner Nature Center, each year's growth produces a ring around the perimeter of the plate; however, Animal Planet asserts that although many experts rely on rings to determine age, judging the age of a turtle by rings on the scutes can be deceiving. Under some circumstances, if the turtle experiences two separate periods of growth in one year, the scute may produce two rings. During periods of slow growth when the turtle nears maturity, the turtle's shell may not produce a ring.
Count the number of rings to determine the approximate age of the turtle. Although scute rings do not provide an exact age, they do provide clues to the overall age of the turtle.
How to Tell How Old a Painted Turtle Is?
Painted turtles sunning themselves on logs and stones along the stream are a common sight in rural parts of the U.S. Emerging in early spring, these slow-moving reptiles absorb the heat of the sun while remaining safely out of reach of predators or the hands of little boys. When danger lurks, turtles disappear by sliding off the rock and plunging deep beneath the surface of the water. If caught, they quickly draw their head and legs beneath their scaly shell. This tough shell provides protection from predators and harbors the secret of their age as well.