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Timber Rattlesnake

I began formal mark-recapture studies on the Timber Rattlesnake in 1973 in the central Appalachian region. ( I had been observing and catching them for about 15 years at that time. ) Approximately two dozen sites, out of several hundred where I found rattlesnakes, located from west-central Virginia northward along the Virginia/West Virginia border, and across Maryland to southern West Virginia, were selected for longterm life history studies.

The Timber Rattlesnake is a long-lived predator of the Eastern Deciduous biome. Individual snakes normally return to the ancestral communal denning area in October and emerge from hibernation in April. Females typically travel from 0.5 to 1 mile away from the den and males 1 to 1.5 miles during the course of the summer. Litters averaging eight snakelings are born in late August and early September. The newborns remain with the female at the birthing site for one to two weeks until they shed their skins. Then the young and their mothers scatter in search of a meal before returning to the overwintering den. Newborns will take shrews and half-grown mice, while adults typically take mice and chipmunks. Timber Rattlesnakes are an important factor in the control of rodents, which are vectors for Lyme disease. Newborns are about 11 inches at birth and reach 18 inches during their first year and 24 inches during their second, and will have a rattle consisting of the postnatal button, two free segments, and a basal segment. During their first six to seven years, the acquisition of rattle segments averages 1.5 per year. Because of rattle breakage, older adults never have a complete string of rattles, so calculating their age accurately is not possible. Adults reach sexual maturity at around 34 inches, which can be at four to five years of age, but females, due to lack of fat, typically do not produce their first litter until they are eight years of age and then produce subsequent litters at three- or four-year intervals, again, contingent on how much fat they can store. Big reproductions typically occur two years after a big mast crop. Females, if they live long enough, eventually reach lengths of 36 to 43 inches and males, 45 to 52 inches. (Rattlesnakes are measured from the tip of the nose to the base of the rattle.) The background color of the Timber Rattlesnake varies from light tan, yellow, greenish tan, or gray, yellowish-brown to dark olive-brown. They have crossbands of brown or black and these are usually edged in yellow. Occasional individuals are a dark, velvety black and the pattern is obscured. There is no consistent correlation between sex and color but females are usually darker than males toward the rear half of the body.

An entire colony may use a single fissure or hole or several closely spaced holes for the den, but more often the "den" consists of a creviced area that may spread out over as much as a quarter-mile of a mountainside. Typical dens in the central Appalachians support 10 to 30 adults and some of the bigger dens have 40 to 80 breeding-age adult rattlesnakes. While populations in remote areas of the Appalachians have remained relatively stable during the course of the study, populations in the Bull Run Mountains have declined precipitously to the edge of extinction. Even the bigger dens in the Bull Run Mountains currently support only about 6 to 12 adults. As late as the 1980s, I typically found three to five females reproducing annually at a couple of sites. In recent years reproduction has averaged about one litter every second year at each of these same sites. Whether this is enough to prevent extinction, remains to be seen. The major factor in their decline has been the rampant residential development and the resulting increase in highway traffic. Rattlesnakes typically take about 30 minutes to cross a typical road and there are few roads in the area that don't have a vehicle pass in that time. People raised in the cities and suburbs typically do not have their eyes attuned to watching for snakes and have usually run over them before they ever see them. Longtime rural residents on the other hand, are more aware of snakes, and usually make a deliberate effort to kill any snake seen on a road. Either way, a rattlesnake rarely makes it across a road.

The Timber Rattlesnake is an inoffensive animal that simply wishes to be left alone. Yes, a rattlesnake is capable of producing a life-threatening bite, and yes, they will defend themselves if stepped on or grabbed. However, most people that are bitten are either attempting to catch or kill the snake or to step on it. Literally hundreds of times I have stepped within a foot of a coiled rattlesnake and never has one attempted to bite. They prefer not to waste precious venom on non-food items, but instead prefer to warn you away with the buzz of the rattle. The danger is exaggerated in the popular mind. A person suddenly encountering a rattlesnake coiled 3 feet away is likely to feel instinctive fear even though there is not the slightest danger from that snake, provided it is left alone. That same person drives up and down the highways with cars zipping by 3 feet away and feels absolutely no fear, yet one moment of inattention on either driver and the occupants of both vehicles are dead or seriously injured.

Should you be unfortunate enough to be envenomated by a rattlesnake, what is the recommended first aid? Get to the hospital and have them call a poison control center. The only other venomous snake in northern Virginia is the Copperhead. Like the rattlesnake, the Copperhead is a pit viper and as such has heat-sensing pits near the nose. Copperheads are smaller than Timber Rattlesnakes, with adults typically ranging from 23 to 34 inches in total length. They have hourglass-shaped crossbands and a plain unpatterned coppery-colored head. Their bite, while serious, is not usually considered life threatening. The closely related venomous Cottonmouth Moccasin has not been recorded north of the vicinity of Petersburg, Virginia