Turtles


Natural History of Turtles
Western Pond Turtle (Clemmys marmorata)
Turtles are fascinating animals that carry their homes around on their backs. They have a hard shell, called a carapace, that encloses all their internal organs. Tortoises are turtles that retract their heads into their shells by pulling their neck into an S-shaped curve. Some turtles hide their heads by bending their necks sideways. Turtles vary in size. Small North American box turtles can be six inches long, while the huge leatherback sea turtles can reach eight feet in length. Turtles do not have teeth. While some turtles are vegetarians, most are omnivorous. Turtles lay their eggs in sand or dirt. A few turtles live a long time, some reaching 100 years. The eggs are leathery, rather than hard like bird eggs. Some pond turtles have webbed feet. One of the largest pond turtles in the world is the alligator snapping turtle. It can get up to 200 pounds. Look for turtle tracks near water. The best time to look for them is the summer or fall. Females come out of the water to lay their eggs in late spring or early summer. They did a hole in soft sand to deposit the eggs in. Some land-dwelling turtles will dig burrows. Sometimes the tail or shell will leave drag marks in the trail. The tracks are almost oval in shape with the toes showing on one side of the oval. There are five toes.
(Clemmys marmorata) Western Pond Turtle

Notice how this pond turtle has drawn its head into the protective covering of its shell. Turtles have many ways of protecting themselves. They are alert and wary and will dive into the water if they are approached too closely. They can remain underwater until the threat goes away, or simply surface only enough to allow the nose to stick above water, allowing them to breathe.

	The left front foot of a western pond turtle. Notice the webbing between the toes. This helps them swim. If you would like to see a turtle swimming, see the Turtle Underwater Videos.

This view shows the toes spread and the webbing is prominent. You can see why turtles are good swimmers. They may move slowly on land, but they are much faster in the water. Their four webbed feet propel them with ease.

	This trail of parallel turtle tracks was found just above the water's edge. Turtles are normally found near water.

A close-up showing several turtle tracks and their size. The claws usually leave good marks, while the feet themselves may or may not make a distinct mark.

	A sandy right front turtle foot.

Nice view of the webbed right hind foot of a pond turtle. When swimming, these webs are spread wide and act as large paddles, moving the turtle through the water with ease.

	The left front foot of a pond turtle folded back to protect the animal. This is the retracted position the turtle holds when it retreats into the shell. The front feet have long claws.

Some nice turtle tracks with prominent claw marks. There are two trails here, one on top of the other. The direction of travel is from bottom to top in the photo.

	Very nice footprints of a pond turtle in sand. The right front and right hind tracks are clearly visible. Damp sand is a great medium for tracking because it holds the shape of the footprint for a long time. Dry sand is the opposite.

	This turtle had crawled up onto a very steep rock face at the base of a cliff above the river. The benefit of this position is that the turtle merely had to let go and slip back into the water and there was a shelf under which it could hide just below the water surface. A perfect place to bask and avoid predators! Notice how closely the turtle is keeping an eye on the photographer too. I was not allowed to get too close. Being reptiles, turtles have to get their warmth from external sources, such as sitting in the sun. They are called exotherms because of this.

Late one afternoon, I came to the river to look for tracks. I found this turtle basking on a rock above water level. It watched my slow approach with caution. When I got too close for comfort, the turtle dove underwater. Small animals have to be wary because predators are always looking for them.

	The river near my home has numerous pond turtles. Unless you spend time really looking at the river, you won't see them. A casual glance often misses the turtles quietly sunning themselves on riverside logs. Sit by the river and look carefully. You will see them.
Late spring and early summer are good times to see the baby turtles. This tiny pond turtle was found in the South Fork of the Eel River in Humboldt County, California.
	Turtles climb onto rocks and logs at the water's edge to sun themselves.
Claws are visible on the hind foot of this baby turtle. Even turtles this size are great swimmers.
	Do you know how hard it is to get a baby turtle to sit still on a ruler so you can get a picture of its size? It's not easy. They don't like to sit still at all. This turtle was about two inches long and full of energy.
This large pond turtle was found in Bull Creek, Humboldt Redwoods State Park, California. Summer 1999.








Turtle Tracks Photo courtesy of Mark Seaver.

	Turtles


	The right front track of a Western Pond Turtle