Rattlesnakes in Pennsylvania State Forests

Pennsylvania Department of Conservation and Natural Resources (DCNR) Bureau of Forestry's 2.2 million acres of State Forest lands provide the largest blocks of timber rattlesnake range remaining in the Northeastern states. These forests are managed according to the principles of ecosystem management, with the realization that all the different species must be present to sustain a healthy, functioning forest.

The presence of timber rattlesnakes is one of the components that gives a wild flavor to State Forest land. The largest populations of timber rattlesnakes occur in the remote, heavily forested regions of Pennsylvania, and the state Wildlife Action Plan recognizes the state's responsibility in maintaining viable populations of native species.

Worldwide, the importance of venomous snakes is being recognized not only for their role as both predator and prey but for their medical value. Recent promising breakthroughs in treatments for hypertension, heart attack, and cancer are attributed to snake venom research.

Pennsylvania experienced a major decline in its timber rattlesnake population during recent decades attributed mainly to unrestricted commercial and sport hunting, den raiding, and land development. This decline prompted the Pennsylvania Fish & Boat Commission (charged with aquatic invertebrate, fish, reptile, and amphibian management) to implement protective regulations and declare the timber rattlesnake a Candidate species for listing (Timber rattlesnakes are listed as threatened or endangered in neighboring states). DCNR urges all State Forest users including recreational visitors, camp lessees, logging, mineral, and rights-of-way contractors, fuel wood cutters, and passers-through to exhibit a tolerance for the timber rattlesnake and abide by all applicable regulations:

• Persons who hunt, capture, kill, or possess timber rattlesnakes must have an Individual Timber Rattlesnake Hunter and Rattlesnake Possession Permit.
• One snake can be taken annually with a valid permit, but the snake must be at least 42 inches in length, measured lenghtwise along the dorsal surface from the snout to tail (excluding the rattle). It also must have 21 or more subcaudal scales. This length requirement protects female snakes as male timber rattlesnakes are larger.
• It is unlawful to hunt, take or kill timber rattlesnakes (even with a valid timber rattlesnake collection permit) west of Route 15 and south of interstate 81 to the Maryland line. Therefore, there is no open season for timber rattlesnake collection in the Michaux State Forest.
• Timber rattlesnakes may not be collected (even with a valid timber rattlesnake collection permit) in the following 28 Natural Areas on State Forest land:

  State Forest	Natural Area
  Bald Eagle	Mt. Logan
  	Rosencrans Bog
  	Tall Timbers
  	The Hook
  Buchanan	Sweet Root
  Delaware	Buckhorn
  	Pennel Run
  Elk	Lower Jerry Run
  	Wykoff Run
  Forbes	Roaring Run
  Gallitzin	Charles F. Lewis
  Loyalsock	KettleCreek Gorge
  Michaux	Carbaugh Run
  Moshannon	Marion Brooks
  Rothrock	Bear Meadows
  	Big Flat Laurel
  	Detweiler Run
  	Little Juniata
  Sproul	Cranberry Swamp
  	East Branch Swamp
  	Tamarack Swamp
  Susquehannock	Forrest H. Dutlinger
  Tiadaghton	Algerine Swamp
  	Berk Cabin
  	Miller Run
  Tioga	Black Ash Swamp
  	Reynolds Spring
  Tuscarora	Frank E. Masland

• Damage to denning or overwintering and basking areas is prohibited.
• Selling timber rattlesnakes or parts thereof is prohibited.
• Timber rattlesnakes are protected under specific regulations by the Pennsylvania Fish & Boat Commission. For more information, consult the most recent "Pennsylvania Summary of Fishing Regulations and Laws" (supplied with fishing licenses) or direct questions to: Nongame and Endangered Species Unit, Pennsylvania Fish & Boat Commission, 450 Robinson Lane, Bellefonte, PA 16823 www.fish.state.pa.us

Scientific Name: Crotalus horridus
Color Phases: yellow (light phase), black (dark phase)
Mating Season: primarily July and August
Birthing: litter of 8-12 in late August through mid-September
Maturity: 5-7 years
Longevity: 30+ years
Mortality Rate: 10-12% annual mortality in adults, possibly higher for immature snakes

Prompted by favorable indicators of ground and air temperatures, Pennsylvania timber rattlesnakes emerge from their six-month long hibernation during late April or early May. Denning or overwintering habitat could be a large outcrop or pile of rocks, or it could be simply a hole in the ground that would go unnoticed by anyone passing by. 

The distinctive tail of the timber rattlesnake is sometimes used as a warning to avoid potential conflicts. The snake rapidly vibrates the tail, giving off a "buzz."
Basking is necessary to ward off parasites and infection and to restore vital functions upon emergence. It also facilitates shedding (1-3 sheds per season) and is crucial to gestating females. Emergence basking may last from several days to several weeks, depending upon the weather and individual needs. Then the rattlesnakes begin dispersing into the surrounding forest where they forage-some will mate-during the course of a summer.

A timber rattlesnake's pattern of movement through the summer range is loop-like, starting at the den with the spring emergence, reaching the apex in July at a mile or more away, and returning to the den in the fall. Along the way, the rattlesnake stops periodically to forage throughout a small area for several days. An adult rattlesnake will typically travel along a similar pathway and through the same general area during each active season of its life.

Foraging timber rattlesnakes are primarily sit and wait predators, stationing along rodent runways to ambush mice, voles, and other small mammals. In an ambush posture typical of Pennsylvania rattlers, the snake positions its head on the surface of a downed snag or fallen branch, often used as runways by rodents.

The strike, injection of venom, and release of prey seem instantaneous, serving to protect the snake from a retaliatory bite. The stricken prey may hobble out of sight, but shortly succumbs; the rattlesnake easily follows the scent trail to find its meal, already partially digested by the venom.

Timber rattlesnakes are extremely well camouflaged and difficult to spot in the forest vegetation.
The frequency of encounters between humans and timber rattlesnakes escalates in July and August when the male snakes actively seek mates. Mature males may travel far and wide (up to 6 miles) in an effort to intersect scent trails of receptive females. This activity, coinciding with Pennsylvania's hot and dry season, is the basis for the misconception that the rattlesnakes are "coming down for water."

During summer months, gravid (pregnant) females that mated the previous summer remain at a basking area typically near their home den through the summer, where optimal thermoregulation conditions help to ensure embryonic development. Around the end of August, pregnant females give birth to live, fully-developed young.

Within about 10 days of birth, the newborn snakes shed their skins and disperse for several weeks of foraging. Although venom-equipped, they are vulnerable to a wide range of predators. Survivors follow the adults' scent trails to the denning sites by mid-October. Rattlesnakes usually return to the same den in successive years throughout their entire life.

With its folding-fang venom delivery system, heat-sensing pit organs, and keratin warning device (rattle), the rattlesnake is perhaps the most specialized reptile in the world. It's the subject of many a campfire story in the hills of Penn's Woods. With your cooperation, timber rattlesnakes will remain a valuable component of Pennsylvania's State Forest lands.

 

Rattlesnakes that take up temporary residence in high use areas such as in or near cottages, residences, and parks should be removed. It is best to contact the local Conservation Officer of the Pennsylvania Fish & Boat Commission to move such snakes.

According to a recent scientific study, displacing a timber rattlesnake 110 yards from its suspected direction of travel is a reasonable solution, considering the well-being of both the snake and the person. The study's subject snakes were able to get their bearings and continue on, not returning to the incident sites. Displacing rattlesnakes long distances has been shown to drastically affect behavior and jeopardize survival.

 

In known timber rattlesnake territory, during the active season of April to October, common-sense precautions will minimize serious encounters with timber rattlesnakes.

• When walking through unmowed grass and brushy areas, wear loose-fitting, full-length pants and high-topped (8") leather boots. Walk at a normal pace so you will not surprise a snake.
• Look for rattlesnakes before you sit down,reach into, over, or under bushes, logs or rocks.
• Be aware that rattlesnakes are attracted to certain structures to hunt for mice and to bask such as a pile of rocks, logs, or boards. They may also be found around a shed or equipment.
• When hiking, step onto rather than over downed logs; this helps prevent stepping on snakes hiding next to logs.
• Never attempt to pick up a rattlesnake, even one that appears to be dead.
   

 

A snakebite from a chance encounter between timber rattlesnakes and people on State Forest land is rare. The snake is generally secretive and docile and normally chooses to move away, hide, or issue a warning in order to avoid a confrontation with an intruder.

When cornered, surprised, or touched, the possibility of a rattlesnake striking in defense (sometimes without warning) becomes more likely. Snakes with "cloudy" eyes are preparing to shed and cannot see well-these snakes may be more likely to defend themselves by striking.

Maintaining a 3-foot buffer around even the largest timber rattlesnakes is sufficient to avoid an effective strike.

Due to the complexity of snake venom and the variables involved in bites and victims, reactions to timber rattlesnake bites vary accordingly: from a "dry bite" (no venom injected in 30% of cases) to a life-threatening situation.

In the rare event of a snakebite:

• Remain calm and reassure the patient. There have been no deaths in Pennsylvania attributable to timber rattlesnake bites for at least the past 25 years.
• If possible, immobilize the affected area and transport the patient immediately to the nearest medical facility.
• Do not attempt first aid measures such as incision, suction, tourniquets, alcohol, or drugs.