For inquiries contact Thomas F. Tyning ,
Herpetologist, Massachusetts Audubon Society
Newborn rattlesnakes have a single segment (the button) and the first new segment is added at the initial shedding, typically within ten days of birth. Each successive shedding produces a new rattle segment, while the oldest segments at the tip are occasionally broken and are lost. It is uncommon to find a rattlesnake with more than 10 or 12 rattles and equally rare to find only 1 or 2 segments. Accurate identification of timber rattlesnakes is complicated by the fact that several New England snakes (black racer, milk snake, hognose) vibrate their tails when cornered -- but not all that rattles is a rattlesnake!!
In colonial times it was believe that males were black and females yellow, though this has been shown to be inaccurate. Albinistic and melanistic individuals are known, though the darkest morphs and most melanistic individuals are not distributed randomly. There are few black morphs west of the Mississippi River, and no melanistic Canebrakes are known. Some researchers suggest that dark-phase individuals prefer mature forests with numerous fallen logs while yellow-phase rattlesnakes are more frequently found in young forests with predominant leaf litter cover. This is possibly a function of background color matching from both would-be prey and predators. Dark morph snakes predominate at higher, cooler, wetter, and more densely forested sites in Shenandoah National Park and in other areas of the Appalachian mountains, especially in the northeast. There is at least one Connecticut River population that appears to have only yellow-morph individuals. Most other locations have a wide mix of color variants.
In New York, mean maximum migrations were 4.07 km by males and 2.05 km by females. These out-migrations bring the snakes into contact with roads, housing developments, well-used hiking and ORV trails, and potential predators. New Jersey snakes moved in a looping pattern, returning to their wintering site by late autumn. All timber rattlesnakes migrate back to their den areas (showing high fidelity to specific locations) in autumn where they retreat until the following spring. One field researcher estimated the active season ranges from 4.6 months to 7.4 months per year throughout the entire range of C. h. horridus. Gravid female timber rattlesnakes do not migrate far from their dens but seek exposed, well-heated rock outcrops where they bask in the open for most of the summer, often several individuals clustering. This behavior and habitat selection make them especially vulnerable to exploitation. Timber rattlesnakes brought in from 13 separate organized rattlesnake hunts in Pennsylvania between 1985 and 1987 were examined. Almost 84% of the mature females that were captured were gravid, and snake hunters indicated that they specifically searched areas that were rocky and exposed.
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Tyning, Thomas F. 1990. Conservation of the timber rattlesnake in the Northeast. Massachusetts Audubon Society, Lincoln, MA.
Tyning, Thomas F. 1990. A Guide to Amphibians and Reptiles. Stokes Nature Guides. Little, Brown and Co. 440 pp.