Nature Notebook – Painted Turtle Nesting

Female painted turtles begin nesting soon, leaving their ponds to dig nests in which they will deposit a clutch of eggs. But, hatchlings have already been spotted by observant hikers. How is that possible?

These young turtles actually hatched late last fall. Instead of heading right to water, like their early fall-hatching compatriots, they hunkered down in their nest for the winter. The warmer spring temperatures triggered the emergence and migration of the hatchlings.

The turtles utilize a physiological adaptation similar to that of wood frogs to survive the winter temperatures. They literally freeze in a controlled manner. The liquid parts of their body develop ice crystals but their cells do not. Once they emerge, the turtles lose the ability to develop anti-freeze and must hibernate protected by soil.