Timber Rattlesnake
Crotalus horridus • Order: Squamata, Suborder: Serpentes, Family: Viperidae, Subfamily: Crotalinae, Genus: Crotalus, Species: Crotalus horridus
Venomous Status
Venomous; solenoglyphous (hinged, front-folding fangs).
Danger Level
Extremely Dangerous. High risk due to large size, significant venom yield, and long fangs. While generally shy, a bite is a life-threatening medical emergency.
Geographic Range
Eastern and central United States, from southern New Hampshire and Vermont to northern Florida, and west to eastern Texas and southeastern Nebraska. Extinct in parts of Canada.
Conservation Status
IUCN Least Concern globally, but considered Endangered or Threatened in many individual U.S. states due to habitat loss and persecution.
Physical Description
Heavy-bodied snake with a triangular head and a rattle on the tail. Base color ranges from gray to yellowish-brown with dark, chevron-shaped crossbands. A dark stripe may be present behind the eye; keeled scales; vertical pupils.
Size & Dimensions
The specimen in the image appears to be an adult, approximately 36 to 48 inches (91-122 cm). Species maximum can reach up to 60 inches (152 cm).
Habitat
Found in deciduous forests, rugged terrain with rocky outcroppings, and lowland floodplains. They prefer areas with southern exposure for basking and deep crevices for winter hibernacula.
Behavior & Temperament
Typically docile and cryptic, relying on camouflage to avoid detection. They are crepuscular or nocturnal during hot months and diurnal during spring/fall. If threatened, they may rattle loudly but prefer to retreat.
Diet & Feeding
Primarily small mammals (squirrels, chipmunks, mice) and occasionally birds. They are sit-and-wait ambush predators that use heat-sensing pits to track warm-blooded prey.
Reproduction
Viviparous (gives birth to live young). Litter size typically ranges from 5 to 14. Females have low reproductive rates, often breeding only every 2 to 4 years.
Venom Profile
Venom Type
Variable; often hemotoxic (causing tissue destruction, bruising, and blood disorders), but some populations in the southern range (lowlands) also contain neurotoxic components.
AI-generated — see a qualified source if acting on this. For any snakebite, call emergency services immediately.
Look-alikes
Eastern Copperhead (lacks rattle, has hourglass bands), Gray Ratsnake (lacks rattle, distinct head shape/pattern), Eastern Hognose Snake (upturned snout, different defensive display).
Conservation Status
IUCN Least Concern globally, but considered Endangered or Threatened in many individual U.S. states due to habitat loss and persecution.
Cultural Significance
Historical icon in the American Revolution (Gadsden flag: 'Don't Tread on Me'). Ecologically vital for controlling rodent populations and preventing Lyme disease spread.
Notable Features
Features a segmented rattle made of keratin and highly sensitive loreal pits (heat-sensing organs) located between the eyes and nostrils for detecting infrared heat.