Introduction
The timber rattlesnake (Crotalus horridus) is a large, thick-bodied snake between 3 and 5 feet long. Individuals may be mostly black or patterned with yellow and brown. They have a broad triangular head and keeled scales that give a rough appearance. At the end of the tail is a large, blunt rattle. In New England, they are listed as extirpated in Maine and Rhode Island, and endangered in Connecticut, Massachusetts, Vermont, and New Hampshire. They are sit-and-wait predators feeding mostly on small mammals. The major threats are fragmentation of habitat from road development and mortality from human persecution. It is listed as a Species of Greatest Conservation Need in all six states in BCR 14.
Habitat Needs
Timber rattlesnakes are deciduous or mixed forest species that require large patches of mature forest with adequate openings in the canopy for basking. Gravid females require exposed basking sites to develop their young. These basking sites typically consist of rocky outcroppings with protective cover such as crevices, patches of dense vegetation and fallen woody material. Thick understory vegetation is important in both closed and open canopy areas. Rocky hillsides with southern exposures and crevices leading to a hibernaculum below frost line are often used communally.
Habitat Management Practices
Canopy openings created through forest harvesting could improve timber rattlesnake habitat by creating foraging opportunities and basking locations for gravid females. Refer to recommendations for the different forest types for additional guidance.
Avoid timber harvests in known timber rattlesnake areas from mid-April to late-October to avoid direct impacts to rattlesnakes.
Allow dead trees and woody material to decompose naturally. After timber harvests, leave stumps, blowovers, logs, dead standing snags, and other woody material to provide foraging opportunities. When whole-tree chipping, fell and leave some low-quality trees.
Rock outcrops are used as hibernacula and basking sites. If shaded, thin or girdle trees to allow significant sunlight to hit the outcrop for improved basking areas for gravid females and snakes coming out of hibernation in the spring.
Sources
Gilbert, M. 2012. Under cover: wildlife of shrublands and young forest. Wildlife Management Institute, Cabot, VT. 87pp.
Clifford, B. and M. Marchand. 2015. Timber rattlesnake. Pages A32-A43 in the New Hampshire Wildlife Action Plan, NH Fish & Game Department, Concord, NH.
Mitchell, J.C., A.R. Breisch, and K.A. Buhlmann. 2006. Habitat management guidelines for amphibians and reptiles of the Northeastern United States. Partners in Amphibian and Reptile Conservation, Technical Bulletin HMG-3, Montgomery, Alabama. 108pp.
PSE&G. 2011. Critical habitat/endangered species mitigation plan for PSE&G's Susquhanna-Roseland 500kV tranmission line project. PSE&G Delivery Projects and Construction, Newark, NJ. 102pp.