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Rattlesnake

Timber Rattlesnake

Venomous

Crotalus horridus

Timber Rattlesnake
Crotalus horridus, © Etienne Falquet
Timber RattlesnakeTimber RattlesnakeTimber Rattlesnake

4 photographs of the Timber Rattlesnake. © Etienne Falquet.

The Timber Rattlesnake (Crotalus horridus) is a venomous snake in the Viperidae family, recorded in 9 countries.

If you are bitten

Rattlesnake bites are medically serious. Expect intense pain, rapid swelling, and bruising. Stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to an emergency room immediately. Do NOT apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call Poison Control at 1-800-222-1222 or 911 in the US, or your local emergency number. (Source: CDC.)

Also called
Rattlesnake
Family
Viperidae
Size
Typically 2–5 ft; some species exceed 6 ft.
Habitat
Deserts, rocky outcrops, grasslands, and woodland edges, depending on species.
Behavior
Ambush predators that buzz the tail as a warning; mostly active in warm months and often crepuscular in summer heat.
Identify
Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
Danger
high

About the Timber Rattlesnake

The timber rattlesnake (Crotalus horridus), also known commonly as the banded rattlesnake, and the canebrake rattlesnake in southern United States is a species of pit viper in the family Viperidae. The species is native to the eastern United States. Like all other pit vipers, it is venomous, with a very toxic bite. Its venom is extremely potent, and both hemorrhagic and neurotoxic venom are present depending on population and location. C. horridus is the only rattlesnake species in most of the populous Northeastern United States and is second only to its relatives to the west, the prairie rattlesnake, as the most northerly distributed venomous snake in North America. There are no subspecies that are recognized as being valid.

Taxonomy

The timber rattlesnake was one of the many reptile species originally described by Carl Linnaeus in the landmark 1758 10th edition of his Systema Naturae, and still bears its original name Crotalus horridus.

The subspecies C. h. atricaudatus (Latreille in Sonnini and Latreille, 1802), often referred to as the canebrake rattlesnake, is currently considered invalid. Previously, it was recognized by Gloyd (1936) and Klauber (1936). Based on an analysis of geographic variation, Pisani et al. (1972) concluded no subspecies should be recognized. This was rejected by Conant (1975), but followed by Collins and Knight (1980). Brown and Ernst (1986) found evidence for retaining the two subspecies, but stating them apart without having more information than usual is not possible, including adult size, color pattern, the number of dorsal scale rows, and the number of ventral scales. Dundee and Rossman (1989) recognized C. h. atricaudatus, but others take a more neutral point of view.

The timber rattlesnake is one of 36 species in the genus Crotalus. This genus can be distinguished from Sistrurus by the small scales atop the head, rather than nine large scales found on Sistrurus.

Etymology

The name Crotalus is Latin for a rattle or, crŏtălisso to rattle or the sound of the castanet. Horridus is Latin, meaning horrid or dreadful, presumably in reference to its potentially lethal venom. Although southern populations are generally no longer recognized as a valid subspecies, the name canebrake rattlesnake (Crotalus horridus atricaudatus) is occasionally still used and commonly encountered in older literature. Atricaudatus is Latin meaning black-tailed (atri = black, and caudatus = tailed).

Description

Adults usually grow to total length of 91–152 cm (36–60 in). In Pennsylvania, the smallest size females that could produce viable eggs was 72.2 cm (28.4 in). Most adult timber rattlesnakes found measure less than 115 cm (45 in) in total length and weigh between 500 and 1,500 g (1.1 and 3.3 lb), often being towards the lower end of that range. The maximum reported total length is 189.2 cm (74.5 in) (Klauber, 1956). Holt (1924) mentions a large specimen caught in Montgomery County, Alabama, which had a total length of 159 cm (62.5 in) and weighed 2.5 kg (5.5 lb). Large specimens can reportedly weigh as much as 4.5 kg (9.9 lb).

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Timber Rattlesnake

Is the Timber Rattlesnake venomous?
Yes. The Timber Rattlesnake (Crotalus horridus) is venomous and belongs to the Viperidae family (rattlesnake). Its bite is considered high risk to people. Treat any bite as a medical emergency.
Is the Timber Rattlesnake poisonous?
Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Timber Rattlesnake is venomous, delivering venom through a bite.
Is the Timber Rattlesnake dangerous?
Rattlesnake bites are medically serious. Expect intense pain, rapid swelling, and bruising. Stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to an emergency room immediately. Do NOT apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call Poison Control at 1-800-222-1222 or 911 in the US, or your local emergency number. (Source: CDC.)
Where does the Timber Rattlesnake live?
The Timber Rattlesnake has verified records in 9 countries, including United States of America, Canada, Mexico. See the distribution section below for its full range.
How do I identify the Timber Rattlesnake?
Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
How big does the Timber Rattlesnake get?
Typically 2–5 ft; some species exceed 6 ft.
What does the Timber Rattlesnake eat?
The prey of the timber rattlesnake are mainly small mammals, in particular mice, rats, squirrels, and rabbits, but may include small birds, frogs, and other small animals. Like most rattlesnakes, timber rattlesnakes are known to use chemical cues to find sites to ambush their prey and often strike their prey and track them until they can be consumed. Timber rattlesnakes are known to use fallen logs as a waiting site for prey to pass by, giving them an el
Why is it called the Timber Rattlesnake?
The name Crotalus is Latin for a rattle or, crŏtălisso to rattle or the sound of the castanet. Horridus is Latin, meaning horrid or dreadful, presumably in reference to its potentially lethal venom. Although southern populations are generally no longer recognized as a valid subspecies, the name canebrake rattlesnake (Crotalus horridus atricaudatus) is occasionally still used and commonly encountered in older literature. Atricaudatus is Latin meaning black-tailed (atri = black, and caudatus = tailed).

If you are bitten by the Timber Rattlesnake

A venomous snakebite is a medical emergency. Call your local emergency number immediately. In the US, dial 911 or Poison Control at 1-800-222-1222.

Do

  • Get away from the snake and stay calm. Most bites worsen when people panic or try again to handle the snake.
  • Call 911 or Poison Control (1-800-222-1222) right away. Antivenom works best when given early.
  • Note the time of the bite and, from a safe distance, the snake's color and pattern, a phone photo is enough. Do not chase it.
  • Keep the bitten limb still and at roughly heart level. Sit or lie down and limit movement.
  • Remove rings, watches, and tight clothing near the bite before swelling starts.
  • Gently wash the bite with soap and water and cover it with a clean, dry dressing.

Do not

  • Do not cut the wound or try to suck out the venom.
  • Do not apply a tourniquet or ice.
  • Do not drink alcohol or caffeine.
  • Do not take aspirin or ibuprofen, they can worsen bleeding. Acetaminophen is safer for pain.
  • Do not try to catch or kill the snake. A dead snake can still bite by reflex.

First-aid guidance adapted from the U.S. Centers for Disease Control and Prevention (CDC NIOSH), Venomous Snakes. Educational only; always follow the instructions of emergency responders.

Where it is found

Snakes it is confused with

More Viperidae snakes

Classification

How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.

OrderThe broad group of scaled reptiles: all snakes and lizards
Squamata
FamilyA group of related snakes that share key traits
Viperidae
GenusA close-knit group of very similar species
Crotalus
SpeciesThis exact snake, named in the two-part scientific name
Crotalus horridus

Keep learning

Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.