Timber Rattlesnake - Crotalus horridus
GENERAL INFORMATION
Rattlesnakes are members of the Pit Viper family, which includes all the venomous snakes found in North America with the exception of the Coral Snake. They are best known for the presence of a "rattle" on the end of the tail. A new segment is added to the rattle each time the snake sheds its skin, which may occur several times a year and rattle segments on the tail periodically break off. When a rattlesnake is frightened or disturbed, it vibrates the tail tip which results in the characteristic buzzing or rattling sound.
DESCRIPTION
The Timber Rattlesnake is a heavy-bodied snake averaging around 3 feet in length with occasional individuals approaching 5 or 6 feet. They vary greatly in overall coloration depending on the region in which they occur. Specimens from the lowlands of eastern North Carolina are typically very light in coloration, often a pinkish-tan with dark black or brown crossbands. Timber Rattlesnakes from the mountain regions of Western North Carolina occur primarily in two varieties, a yellow phase and a black phase. The yellow phase tends to be more common in most areas. Yellow phase Timber Rattlesnakes have a background coloration of yellow or tan with brown or black crossbands. Black phase Timber Rattlesnakes are sometimes almost solid black in coloration but usually sport the same pattern as the yellow phase with the yellow or brown being replaced by much darker pigments. Contrary to popular opinion, the sex of a Timber Rattlesnake cannot be determined by its color phase. Because of its many different color varieties, people often mistake the Timber Rattlesnake for other rattlesnake species, particularly the Eastern Diamondback Rattlesnake; however, the Timber Rattlesnake is the only species of rattlesnake found in Western North Carolina. Like other pit vipers, the head of the Timber Rattlesnake is very broad in comparison to the neck. The pupils of the eyes are elliptical in shape (in bright light only), and there are heat-sensitive pits, one on either side of the face, between the eye and nostril.
HABITS AND HABITATS
Like other snakes, the forked tongue of the Timber Rattlesnake is used for smelling. It trails the stricken animal with its sensitive tongue to wherever the prey has fallen. Interestingly enough, if the snake strikes a bird, it does not let go, instinctively knowing that a bird will fly away, not leaving a scent trail upon the ground that the snake could follow. Then, usually beginning with the head, the Timber Rattlesnake swallows its prey whole. Days or weeks may pass before the Timber Rattlesnake has an opportunity to feed again.Timber rattlesnakes bear live young during late summer or early fall. Litters range from around five to nineteen young which are totally on their own from birth, receiving no care from the female.
HISTORY
The Timber Rattlesnake occupies a variety of habitats depending on the time of year. Summer ranges include heavily forested areas, rocky hillsides, and fields bordered by forests. In early fall, Timber Rattlesnakes begin moving towards their winter hibernation dens which are typically rocky outcrops with deep crevices leading well below the frost line. Rattlesnakes often congregate near the den opening, sunning on warm rocks by day and then crawling inside for protection as the temperature falls at night. Eventually, cold temperatures cause them to remain underground in a dormant state, hibernating until the following spring. Timber rattlesnakes bear live young during late summer or early fall. Litters range from around five to nineteen young which are independent from birth, receiving no care from the female. Timber Rattlesnakes are primarily nocturnal, but may be encountered by day as well. They feed on a variety of small mammals, primarily rodents such as rats, mice, chipmunks, and squirrels. Rattlesnakes may wait quietly for their prey or actively hunt their prey by investigating underground burrows, crevices, and other similar locations. Their heat-sensitive pits help them to pinpoint warm-blooded prey. They kill their prey by injecting venom, a modified and highly specialized form of saliva. The venom is conducted through a pair of fangs in the front upper jaw. Like other snakes, the forked tongue of the Timber Rattlesnake is used for smelling.
HISTORY
Although still common in some locations, the Timber Rattlesnake is rapidly declining throughout much of its range, primarily due to habitat destruction and intense persecution by man. Although most people believe that rattlesnakes are quite aggressive animals, in reality, they are not very aggressive animals. When encountered, most Timber Rattlesnakes will lie quietly, relying on their concealing coloration to protect them from a potential enemy. It is normally only in self-defense, when disturbed or stepped upon, that the Timber Rattlesnake will rattle its tail and strike. Although the Timber Rattlesnake is venomous, very few human bites are recorded and fatalities from bites are extremely rare. These beneficial snakes occupy important niche in our forests and if encountered, would rather be left undisturbed.
MEET OUR TIMBER RATTLESNAKES
The Nature Center has three Timber Rattlesnakes currently on display. These rattlesnakes are long-term captives and have lived at the Nature Center for several years. They were originally wild caught in the Western North Carolina area. They are each fed 2 to 3 pre-killed (to prevent injury to the snakes) rats once every 10 days to 2 weeks. Being cold-blooded, their metabolism is much slower than warm-blooded animals and therefore don't have to be fed as often. Timber rattlesnakes normally have a long lifespan in comparison to many other snake species.



