Western Diamondback Rattlesnake
Crotalus atrox • Order: Squamata, Suborder: Serpentes, Family: Viperidae, Subfamily: Crotalinae, Genus: Crotalus, Species: Crotalus atrox
Southwestern United States (Arkansas, Oklahoma, Texas, New Mexico, Arizona, southern California, southern Nevada) and northern to central Mexico.
Look up Western Diamondback Rattlesnake in the Snake Encyclopedia →Venomous Status
Venomous (Solenoglyphous)
Danger Level
Extremely Dangerous; it is responsible for the majority of serious snakebite incidents in North America due to its large size, high venom yield, and irritable temperament.
Family
Order: Squamata, Suborder: Serpentes, Family: Viperidae, Subfamily: Crotalinae, Genus: Crotalus, Species: Crotalus atrox
Conservation
IUCN status: Least Concern. Populations are stable, though threatened locally by habitat loss and 'rattlesnake roundups'.
Physical Description
Heavy-bodied with a triangular head. Coloration is gray, tan, or brown with dark, diamond-shaped dorsal blotches outlined in white. Features keeled scales and a distinctive 'raccoon tail' with alternating black and white bands near the rattle. Eyes have vertical elliptical pupils.
Size & Dimensions
Specimen appears to be an adult approximately 3-4 feet in length. Species typically ranges from 120-150 cm (4-5 feet), with exceptional specimens reaching over 200 cm (6.6 feet).
Habitat
Desert, rocky hillsides, shrublands, and grasslands; found from sea level to about 2,100 meters (7,000 feet). They often seek shelter in rodent burrows or rock crevices.
Behavior & Temperament
Primarily crepuscular or nocturnal during hot months. Generally highly defensive; frequently assumes a coiled S-position and vigorously shakes its rattle to warn intruders. It will strike if it feels cornered or threatened.
Diet & Feeding
Active forager and ambush predator targeting small mammals (rabbits, gophers, rats), birds, and occasionally lizards. Dispatches prey via venom injection.
Reproduction
Ovoviviparous (gives birth to live young); typical litter size ranges from 4 to 25. Breeding occurs in late summer/autumn, with young born about 6-7 months later.
Venom Profile
Complex mixture of enzymes and proteins featuring hemotoxic, cytotoxic, and myotoxic properties. It causes tissue destruction and interferes with blood clotting.
Look-alikes
Often confused with the Mojave Rattlesnake (Crotalus scutulatus), which has narrower white bands on the tail, or the Timber Rattlesnake (Crotalus horridus) which lacks the distinct diamond pattern.
Conservation Status
IUCN status: Least Concern. Populations are stable, though threatened locally by habitat loss and 'rattlesnake roundups'.
Cultural Significance
A cultural icon of the American Southwest; featured in Native American folklore, the 'Don't Tread on Me' Gadsden flag, and extensively in Western cinema. Ecologically vital for rodent population control.
Notable Features
Equipped with heat-sensing loreal pits between the eyes and nostrils to detect warm-blooded prey in the dark, and a keratinous rattle used as an auditory warning signal.