The Timber Rattlesnake is a large,
stout-bodied snake measuring on average 38 to 43 inches (97 to 111 cm).
Males are slightly larger than females. The scales are keeled; the head
is broad and, unlike most nonvenomous snakes, noticeably wider than the
neck (often referred to as “triangular”). The dorsal background
coloration is variable, but most individuals range from gray, to
mustard yellow, or black. A series of dark bands, often outlined in
white or light yellow, traverse the body. The banding in “black color
morphs” may be indistinct. Occasionally, individuals will have a light
rust stripe running along the dorsum, or dark brown spots that tend to
become bands toward the tail. The tail itself is often completely dark
brown or black with no banding. Some individuals are nearly uniform
black from nose to tail.
The tail ends in a distinct rattle, not seen on any other Connecticut snake. The eyes have slit-like elliptical pupils like that of a cat, and there is a noticeable loreal pit between the eye and nostril on each side of the face. The body is generally flattened dorsoventrally. Young snakes are typically gray with dark banding, often with a light rust stripe running along the dorsum. They average about 12 inches (30 cm) in length and have a “button,” the first segment of their rattle, on the end of the tail.
The Timber Rattlesnake is venomous.
Live-bearing. Timber rattlesnakes give birth to 6 to 14 young, August through September. Individual females reproduce at 2- to 4-year intervals, with perhaps as few as 3 to 5 reproductive events per lifetime (see Klemens 1993).
An inhabitant of deciduous and mixed forests associated with rocky ledges and open rock outcrops. Timber Rattlesnakes have a wide home range centered around a den site or hibernaculum that is used for over-wintering. Dens are typically located on steep rocky ledges or talus slopes along ridges. In the southern part of the snake’s range, den sites may be associated with wetland habitats. During the active season individual snakes may travel from 1 mile to more than 4 miles from a den. In females, habitat use in a given year depends on reproductive condition.
Feeds almost exclusively on warm-blooded prey. Prey items include rodents and birds.
Timber Rattlesnake populations are distributed from the midwestern to the eastern United States, and throughout the South, except for southern Florida. Historically populations occurred throughout New England; however, Timber Rattlesnakes are believed to be extinct in Maine and Rhode Island. The species is known from nearly every state in the eastern United States, although the southern forms are a different subspecies. In nearly every state throughout most of its range in the U.S. populations have declined significantly. In Connecticut, rattlesnakes are now known from only a handful of localities.
Not federally protected, but the Timber Rattlesnake is listed as endangered, threatened or of special concern in many states throughout its range. Considered an endangered species in Connecticut. Currently, habitat loss and illegal collection are primary factors in population declines. Historically, bounties on rattlesnakes played a significant role in population reductions and localized extirpations.
debate whether or not populations of Timber Rattlesnakes in the
southern and midwestern United States represent separate subspecies.
Rattlesnakes belong to a family of snakes referred to as “pit vipers,”
so named for a pair of heat-sensing pits located on the face. These
sensory organs are used as an aid in detecting warm-blooded prey.
Reminder: A wild snake should never be handled if it cannot be readily identified. Venomous snakes should not be handled by the novice under any circumstances. If left alone and unharmed, even the most venomous species will pose no threat to humans. It is only when threatened by a human that a snake will bite, and then only in self-defense. The Timber Rattlesnake is venomous.
Brown, W.S. 1993. Biology, Statues, and Management of the Timber Rattlesnake (Croatlus horridus): A Guide for Conservation. Society for the Study of Amphibians and Reptiles, Herpetological Circular 22. 84 pp.
Campbell, J.A. and E.D. Brodie Jr., editors. 1992. Biology of the Pitvipers. Tyler, TX: Selva Press. 467 pp.
Conant, R. and J.T. Collins. 1991. A Field Guide to Reptiles and Amphibians: Eastern/Central North America. Boston: Houghton Mifflin. 450 pp.
Klemens, M.W. 1993. Amphibians and Reptiles of Connecticut and Adjacent Regions. Hartford, CT: State Geological and Natural History Survey of Connecticut Bulletin 112. 318 pp.
Petersen, R.C. and R.W. Fritch II. 1986. Connecticut’s Venomous Snakes: The Timber Rattlesnake and Northern Copperhead, 2nd edition. Hartford, CT: State Geological and Natural History Survey of Connecticut Bulletin 111, 1986. 48 pp.
Text by Hank Gruner and Gregory J. Watkins-Colwell.
Photograph © Twan Leenders. All rights reserved. Used by permission.
Animals featured on this page are from Connecticut.