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The Naturalist: |
Turtles |
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The Naturalist: |
Turtles |
There are six species of turtle that definitely are at home in New Hampshire and a possible seventh whose presence and fate are precarious. Of these, the ones most often seen are the Snapping and the Eastern Painted Turtle.
The largest of our turtles is the Snapping Turtle. By the time they are sexually mature their shells are usually at least ten inches long and they continue to grow. These animals are uniformly black with a very long, spiny tail. They are mostly aquatic, leaving ponds only to lay their eggs or move to a new location. Most of their time is spent buried in leaves and mud at the bottom of ponds waiting for prey to approach. Although they are omnivorous feeders and at times have been known to take young waterfowl, snapping turtles are not considered destructive to natural populations of fish or birds. Snapping turtles are usually seen starting in mid-June. The females tend to be loyal to certain nesting sites where they return year after year usually laying twenty to thirty eggs at a time. The eggs hatch from August to early October but the young may overwinter in the nest until the following spring. Although not an aggressive species, their jaws are strong and their necks very long, so they must be handled carefully if at all. For information about helping this species and the Eastern Painted Turtle out of a potentially dangerous situation during the nesting period, please see Nesting Turtles.
The most common turtle and the one most often seen is the Eastern Painted Turtle which spends a considerable amount of time basking in the sun. In addition to yellow stripes on its face, it has red markings around the edge of its shell. The male of the species has long claws on the front feet and a long tail. His bottom shell is somewhat concave. The females have short claws and stubby tails. Like the Snappers, these turtles lay their eggs on land in June with hatching occurring in September. The hatchlings often spend the winter in the nest, emerging the following spring.
The most aquatic of New Hampshire's turtles, and the smallest is the Musk Turtle, also know as Stinkpot. Only three-and-a-half to five-and-a half inches in length, these turtles leave the water only to nest. They are most active at night but someone at the shore of a pond or lake very early in the morning may lure them closer by the use of a tempting tidbit - pieces of freshwater clam or fish will do. Their most distinguishing feature is a pair of yellow lines on each side of the head that go from the tip of the nose along the face, around the eye, and onto the neck. Nesting takes place close to the water and while shallow nests are sometimes dug, the egg clutch, usually averaging only four or five, is often deposited in rotting logs or leaf litter. These eggs, too, take from two to three months to hatch and the babies may opt to emerge the following spring rather than in the fall.
The earliest turtle to emerge in the spring, often appearing in March while snow is still on the ground, is the Spotted Turtle. These turtles are small and each one has a distinctive pattern of yellow spots on its carapace and face. They prefer shallow ponds and wetlands and often show up at vernal pools to feed. Spotted Turtles are of special concern in New Hampshire due to the loss of habitat and their slow reproduction rate. Females usually lay only 4 or 5 eggs and very little is known about hatchling behavior. While the eggs take from two-and-a-half to three- months to hatch like the species discussed above, it is not known whether the young attempt to overwinter in the nest. Spotted Turtles are more apt to be seen on cold, sunny days than in warm weather. They are unusual in that they do not like the heat and practice estivation, the warm-weather equivalent of hibernation.
Another turtle of special concern here is the Blanding's Turtle. These turtles are fairly large (10.5 inches long) and are distinguished by a helmet-shaped carapace and bright yellow chin and throat. They spend most of their time in the water and have extremely long necks so that they can extend their heads to the surface to breathe while keeping their bodies out of sight. Like the Spotted Turtle, the Blanding's likes feeding in vernal pools. Nesting usually takes place along the edges of fields or in forested areas with open canopies that are close to water. Eggs hatch in August or early September and, as with the Spotted, not very much is known about the hatchlings.
A characteristic that all of the above turtles have in common is that the sex of their offspring depends on the temperature around the egg at a crucial time of embryo development. Females develop in areas with the coolest and warmest temperatures and males hatch from the area between the two extremes.
While the Eastern Box Turtle was once known to roam the woods of New Hampshire, especially in its southern portion, they were so extensively collected that any seen today are thought to be escaped or released pets. We are able, however, to boast of a terrestrial species - the Wood Turtle. These turtles are quite different from their pond-loving relatives. Their top shells are made up of low, pyramid-shaped plates and are sculpted and bumpy rather than smooth and shiny. Males have dark skin with orange markings under their chins, on their throats, and on the inner parts of their legs. Females are lighter in color with lighter markings. Active in forested areas all summer long, they overwinter in deep, clear, slow-moving streams. An elaborate courtship dance takes place on land before they go into the water to mate and a clutch averages four to twelve eggs. They are unusual in that the sex of the offspring is genetically determined rather than dependent on temperature. Very little is known about the hatchlings as they are seldom seen.
Humankind went through a number of stages before achieving its current evolutionary configuration. Turtles were a perfect design from the start and have remained virtually unchanged since the time of the dinosaurs. Observing turtles is a glimpse into an ancient and mysterious world. They are worthy of our respect.
Anyone interested in learning more is urged to read The Year of the Turtle beautifully written and illustrated by David Carroll.
Further information on turtles: