In spring and summer, it is common to see a variety of turtles in and around ponds, streams, marshes and freshwater rivers in woodland and wetland New England habitats. Painted turtles like to congregate on logs or rocks in ponds during morning or afternoon, between periods of foraging. The more shy spotted turtle prefers marshy pastures or streams in woodland areas, basking on logs or clumps of grass.
A female snapping turtle may be seen crossing a backyard or road to find a dry area away from water to lay her eggs. The box turtle and wood turtle, as more land-loving species, prefer bogs or marshy meadows, and like to bask in the morning. The musk turtle, also called the “stinkpot,” is nocturnal like the snapping turtle, so it stays buried in the mud all day, but may be spotted floating just beneath the water’s surface if it decides to bask. The diamondback terrapin is one of two turtle species that prefer brackish water, and it loves to bask in the daytime and sleep in the mud at night.
Turtles Unable to Regulate Body Temperature
While each species might prefer different ways or times of day to bask and be active, what they have in common is that these turtles, like all reptiles, are considered “cold-blooded”—that is, they are unable to regulate their body temperature and must use their environment to warm up and cool down.
In the warmer months, the sun heats their bodies, speeding up their metabolism, enabling them to be more active. When they are in danger of overheating, they can retreat into the water, mud, or beneath a pile of leaves to cool down. The land-loving box turtles, for instance, take shelter from heat under logs, decaying vegetation, or in soft mud. Each species has its own threshold for tolerance of the heat. The diamondback terrapin, for example, is quite tolerant of high temperatures and drying out while basking on mud flats, whereas the stinkpot will seldom emerge from the water, spending most of its time on the muddy bottom..
Hibernation Keeps Turtles Alive
But when winter comes to New England, how does a turtle keep warm when the sun isn’t as strong, the water chills, and ice forms? Where do the turtles go? Like the way of many animals preparing for winter, the turtle eats a lot to shore up its energy reserves. Depending on the species type and age, the turtle may be an omnivore or herbivore, but most of these northeastern turtle species feed like scavengers on a variety of algae, aquatic plants (living or dead), crayfish, worms, snails, insects tadpoles and more.
Anywhere from late September to November, when the temperature drops, the turtle will find a muddy spot in the bottom of a pond or stream, or in the case of the terrestrial box turtle, dig a hole in the ground somewhere, to burrow for hibernation. A snapping turtle or stinkpot might retreat into a muskrat lodge, or dig under a log, burying itself as much as a foot deep. A painted turtle might dig up to 18 inches into the muddy bottom of a pond to stay for the winter.
During hibernation, the turtle’s system slows way down and it no longer uses its lungs for respiration. The turtle absorbs any oxygen it needs from the water around it, through the lining of its mouth or throat. The chemical composition of the turtle’s blood changes so it doesn’t freeze up when the metabolism is so slow.
In some instances, a turtle—or group of turtles—will use the same hibernating spot from winter to winter. Some, like painted turtles, might emerge from hibernation if there is a warm spell, but if a turtle emerges from hibernation too soon, and there is a sudden dip in temperature, it might not survive. Some turtles have been observed crawling under the ice in mid- to late winter. Hibernation is generally over sometime in March or April. After hibernation, turtles will reproduce and nest during late spring and early summer.
The landmark 1972 book Turtles of the United States by notable herpetologists Carl H. Ernst and Roger W. Barbour was used in part to research this article. This comprehensive guide citing scientific observations on individual species’ population, habitat, movement, reproduction and more, has become a standard reference for scholars, and has since been updated to include new information and contributions by Jeffrey E. Lovich.
Nature Note
Anyone who encounters a turtle crossing a road should leave it alone, and stop only to help it cross to the other side if danger is near. Do not remove the turtle from the area or reverse its direction. The turtle is following its instincts and movement pattern, and will only repeat its course. Use gloves and hold the turtle by the sides of its shell, with the exception of snapping turtles—they will bite, and can reach as far as their back legs. It is best to gently grasp a snapper's tail with one hand, then support the belly with the other hand, coming at it from behind.
Photo: Painted turtles on log at Nequasset Lake in Woolwich, Maine, courtesy Laurie LaBar.
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