Snakes do not produce heat internally as mammals do. Instead, they must rely on an external source of heat, like the sun, to reach certain temperatures before they can be very active. Snakes can be found in almost every habitat in North America except the Arctic Tundra.
Pit vipers are venomous snakes that are named for the two heat sensing pits used to locate warm blooded prey that are positioned between the eyes and the nostrils. Their venom is hemolytic, which means it destroys the red corpuscles of the blood and releases the hemoglobin into the surrounding fluid. This results in the hemorrhaging of tissue and destroys the snake's normal prey.
Western Diamond Backed — Length 24 to 60 inches. May reach lengths up to seven feet. This snake will not back away when confronted.
Timber — Length 24 to 54 inches
Copperhead — Length 15 to 30 inches. Most common snake bite in the United States, usually from being stepped on.
Western Pygmy — Length 10 to 15 inches
Snakes do not have ears, but are very sensitive to vibrations. A rattlesnake cannot hear its own rattle; it only feels the vibration.