Timber Rattlesnake (Crotalus horridus)

 

 

Timber Rattlesnake

(Crotalus horridus)

venomous*

 

At a glance: The Timber Rattlesnake is a venomous, but typically docile, pitviper of the eastern United States. This species occurs in both mountains and swamps, and is protected in many parts of its range.

*This snake is a pitviper with large front fangs. This species should be approached with care, and only handled by professionals. While typically docile, this species can and will bite. The venom is potent, and can cause severe injury or death. If bitten seek emergency medical care immediately. 


Quick Facts:

Scroll down for deeper look at each section

 

Common Names: Timber Rattler, Velvet Tail, Canebrake, Diamondback (incorrect)

Identification: Thick body, rattle on tip of tail, rough (never shiny) appearance.

Range: United States: New Hampshire south to Florida, west to Texas, North to Minnesota. Canada: Ontario.

Black: Extirpated, Orange: Threatened, Red: Endangered.
Timber Rattlesnake occurrence by state. Black: Extirpated, Orange: Threatened, Red: Endangered. Extirpated in Ontario, Canada. Map created by the author.

Activity: Diurnal (day), Nocturnal (night), Crepuscular (dawn and dusk)

Diet: Small mammals, occasionally birds and reptiles.

Habitat: Habitat generalist. However, due to widespread habitat loss and persecution, this species is now mostly found in mountainous areas and swamps.

Herping Tips: This species can be sensitive to disturbance, particularly around winter dens and rookeries. Try not to disturb this imperiled snake during the early spring, late summer, and fall.



In Depth Information:

  Identification:

Pattern and Color: The Timber Rattlesnake (timber) is a highly variable species, and can range from melanistic (black) to to bright yellow. In general, this snake has a light background with dark chevrons (marks that look like a sideways “V”). There is often a pale dorsal stripe (line down the back). Freshly hatched snakes are typically pale grey with dull marks, which lighten with each shed, including snakes that will eventually be completely black.

    • Snakes in the southeast are typically pale grey to pink, with reddish-brown dorsal stripe, and a dark post-ocular (behind the eye) stripe.
    • Snakes in the western portion of this species’ range also tend to be grey or pink, but with a more reddish/orange dorsal stripe, and a reddish-brown post-ocular stripe. They may also have white edges to their chevrons.
    • Snakes in the northeast tend to be either yellow or black, with yellow snakes lacking a post-ocular stripe, and melanistic snakes being completely or partially black.

A sample of the variation in this snake is show below. Information on the different regional color varieties paraphrased from The Reptiles and Amphibians of Eastern/Central North America, by Conant and Collins.


Head: The head is broad and flat. The eyes are small but prominent, and the pupils are vertical. There is a loreal (heat) pit between the eyes and nostrils, used to sense infrared radiation. Inside the mouth are a pair of fangs, used to inject venom.

Key features in the head of a timber rattlesnake.
Key features in the head of a timber rattlesnake.

Body: This snake is heavy set, and a 6 foot snake can exceed 5 pounds in weight.

The author (6'3) with a 5+ lb timber rattlesnake. This snake was being handled as part of a scientific study and was prefaced by extensive safety training. Please do not attempt to handle wild rattlesnakes.
The author (6’3) with a 5+ lb timber rattlesnake. This snake was being handled as part of a scientific study and was prefaced by extensive safety training. Please do not attempt to handle wild rattlesnakes.

Size: Baby timber rattlesnakes snakes are typically between 7 and 16 inches long. Most adults snakes are between 3 and 5 feet, but the largest individuals max out at 6 feet 2 inches. Snakes longer than this should be reported to a professional herpetologist, but care should be taken to ensure lengths are not exaggerated.

Photography tricks should be taken into consideration before believing “giant” snake claims. Photo from http://www.livingalongsidewildlife.com/2009/07/return-of-giant-killed-rattlesnake.html

 

 


Behavior: The Timber Rattlesnakes is generally a placid snake, ignoring the presence of people. However, when agitated, the snake will use its tail rattle as a signal to the predator. This rattle is a warning, and this snake can strike up to half its body length or more. Do not approach wild rattlesnakes, just observe from afar. It is commonly thought that these snakes chase humans, but this is a myth. Given the chance, snakes will flee. Snakes that are not rattling can still strike and all rattlesnakes should be considered dangerous.

When hunting, this snake will often wait in ambush against a log, tree, or branch. The body will be coiled, with the upper body poised and tense. Timber rattlesnakes can remain in this hunting position for hours.

An Indiana timber rattlesnake waiting in ambush. Photo taken by the author.
An Indiana timber rattlesnake waiting in ambush. Photo taken by the author.

 


Range:

Current and historic range of the Timber Rattlesnake. Photo copywrite: The Orianne Society: http://www.oriannesociety.org/sites/default/themes/orianne/images/rangemaps/Timber_Rattlesnake1.jpg
Current and historic range of the Timber Rattlesnake. Learn more about this map and the conservation of this species at http://www.oriannesociety.org/timber-rattlesnake

Activity: Timber Rattlesnakes are most active during the spring and fall, as they emerge and enter their winter dens. In colder portions of their range, they may be limited emerge from their dens as late as May, and enter hibernation in October. In warmer regions, they may be active during every month of year, but limit winter activity to the warmest, sunniest days. This snake is diurnal, but may be active at night during the summer, particularly in the southern portion of their range.


Diet: This snake eats mostly rodents, but will occasionally eat small birds.

A large male Timber Rattlesnake eating a Grey Squirrel. Photo by the author.
A large male Timber Rattlesnake eating a Grey Squirrel. Photo by the author.

Habitat: Historically this snake was a generalist, occupying a wide range of habitats and geologic regions. Today, this snake is limited to wilder areas, with less human impact. In the northeast, Timber Rattlesnakes have been pushed back to the mountains, with small isolated populations. Of particular note are the snakes still left in the New Jersey Pine Barrens. In the south, they are snakes of both coastal plain swamps and Appalachian Mountains. Snakes living at higher elevations areas of low canopy cover, such as rock outcroppings, to bask and reach optimal body temperatures. These mountain snakes often den communally, whereas southern swamp snakes may den individually.


Herping Tips: Down south, these snakes can be found under cover objects such as tin sheets or wooden boards, or found crossing roads in the early morning/early evening.

 

In the northeast, this snake is becoming increasingly rare, so protecting locality information is very important! If you see a Timber Rattlesnake, make sure you don’t disclose that information to the public, and remove the GPS coordinates from any digital pictures you share!


 

John with tortoise

About the Author: John Vanek is a Master’s candidate at Hofstra University,where he studies the ecology of Eastern Hog-nosed Snakes. He received a BS in Wildlife Science from the SUNY-College of Environmental Science and Forestry in 2010. John has been fortunate enough to study a wide range of wildlife, including Eastern Hellbenders, Timber Rattlesnakes, Black Bears, and Peregrine Falcons. He has worked as a wildlife technician and environmental consultant for several companies, universities, and organizations. John can be reached on Twitter @Nomadofthehills and Instagram @johnpvanek. He is also a moderator for the 2,500 member facebook group Snake Identification.

Be sure to visit John’s article on the Eastern Hog-nose Snake