Saturday, August 09, 2008

Snakes in the Swamp

It'sssssssss sssssssssummer in the ssssssssswamp! The hot weather has kept the swamp's five species of snakes relatively inactive and difficult to many of us! Snakes, like other reptiles, warm their bodies mainly by lying in the sun, but it is possible for reptiles to get too hot. Since reptiles do not need calories to maintain a warm body temperature, there is little reason for them to move about when it's hot. The Red-bellied Water Snake below has found a sunny spot on a fallen tree over the water. Not only is the snake in direct sunlight, should danger approach, it can also make a quick escape by dropping to the water below.

Another water snake seen from the boardwalk this week is the Banded Water Snake. The individual shown below is close to black with the dark red bands rising from its belly to its back.

The Banded Water Snake shown below is slightly lighter in overall color, it still shows the dark red bands rising from its belly to its back, but it is also showing its light belly as it repositions itself on the sunny log. When at rest, the lighter belly does not show making the snake harder to detect in its environment.

The juvenile (teenager) Red-bellied Water Snake shown below appears to be a Banded Water Snake with slight traces of red bands rising from its belly. Variations in markings and color within the same species can make identification difficult, so we do not need juveniles trying to confuse us too!

The third species of snake in the swamp is the Greenish Rat Snake. The Greenish Rat Snake is a combination (integrade) of the Black Rat Snake, which is found farther to the west, and the Yellow Rat Snake, which is found closer to the coast and south. Greenish Rat Snakes are superb climbers. They can climb straight up the tallest Bald Cypress tree, find a meal, and climb straight back down the tree.

The only venomous snake in the swamp is the Eastern Cottonmouth. Notice the triangular shape of the head. That is the biggest clue that this is a snake that needs to be given plenty of room. Like the other water snakes, the Cottonmouth eats mainly fish and amphibians (frogs, salamanders, toads), though it will eat small mammals, birds, lizards, and snakes. Notice the forked tongue that this Cottonmouth is using to hunt for its prey. Chemical traces in the air stick to the tongue, which the snake then sticks into receptors in the roof of its mouth. The receptors are connected to the brain, which helps the snake determine if suitable prey is nearby. If more chemicals stick on the left fork of the tongue, the snake knows that it must move in that direction to find its prey.

Most of the time, snakes will leave people alone. Snakes are basically a long backbone. (Yes, they DO have a backbone and even ribs... lots of them!) Even the smallest human can snap the back of a snake. Therefore, snakes attempt to avoid detection by using camouflage or remaining perfectly still. If detected, snakes will often attempt to flee. If not allowed to flee, snakes may hiss, fake a strike, or show off their "cotton" mouth. If all this fails to convince the human to go away, the snake may bite.

Notice in the image above that the fangs of the Cottonmouth are not descended. If the snake were to strike out, the fangs would descend before impacting the prey or the unwise human.

Look at the image below and see if you can detect the two Banded Water Snakes and the fish-eating Brown Water Snake, which is the last of the five species in the swamp at Beidler Forest.

Banded and Brown Water Snakes - images may be used for educational purposes only

If you didn't find them all before you scrolled s..l..o..w..l..y over them with your cursor, you probably need to watch you ssssssssstep when you go outside!

Images by Mark Musselman

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