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Snakes

Western Diamond-backed Rattlesnake

Crotalus atrox

Across the regions where it's common, the Western Diamond-backed Rattlesnake peaks from March to October.

Shows up in 12 ecoregions and 5 states · venomous

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Snakes

Western Diamond-backed Rattlesnake

Crotalus atrox

venomous
Venomous. Do not handle. Give it room and let it move on. If you're bitten, call 911 or go to an emergency room. Don't cut, suck or ice the bite.
Look, don't take. Many states regulate collecting reptiles and amphibians. Photograph it, log it on iNaturalist and leave it where you found it.

Description

The western diamondback rattlesnake (Crotalus atrox) or western diamond-backed rattlesnake, is a rattlesnake species and member of the viper family, found in the southwestern United States and Mexico. Adults commonly grow to 120 cm (4 ft) in length.Wikipedia ↗

Habitat

It is found in the United States from central Arkansas to southeastern and Central California, south into Mexico as far as northern Sinaloa, Hidalgo and northern Veracruz. Its habitats range from flat coastal plains to steep rocky canyons and hillsides; it is associated with many different vegetation types, including desert, sandy creosote areas, mesquite grassland, desert scrub, and pine-oak forests.Wikipedia ↗

When it's active

C. atrox is solitary except during the mating season, when males of the species are single-minded and aggressive in pursuing females. Active, alert, and large (most adults are between four and a half and five feet long), the western diamondback can administer a large amount of venom in its bite; it is not inclined to give ground when confronted.Wikipedia ↗

Venom

Like that of most other American pit vipers, the venom contains proteolytic enzymes. Proteolytic venoms are concentrated secretions that destroy structural tissues and proteins via catabolism, which help in disabling prey.Wikipedia ↗
Sam Kieschnick · CC BY 4.0

Harmless look-alikes

Gopher Snake, Pine Snake, Eastern Hognose Snake, Plains Hognose Snake, Mexican Hognose Snake, Prairie Kingsnake, Desert Nightsnake, Chihuahuan NightsnakeSuperficially, gopher snakes resemble many species of rattlesnakes and are often mistaken for them. Animal Diversity Web ↗Non-human predators are likely to be discouraged from attacking gopher snakes when they are mimicing rattlesnakes. Animal Diversity Web ↗Rattlesnakes vs. gopher snakes, bullsnakes and hognose snakes →

When and where it's active

Each row is its own calendar, counted from records in that area. Seasons shift by place.

PeakShoulderQuiet

Ecoregions

States

JanFebMarAprMayJunJulAugSepOctNovDec
ArizonaCaliforniaNew MexicoOklahomaTexas

About the Western Diamond-backed Rattlesnake

When is the Western Diamond-backed Rattlesnake most active?

Across the regions where it's common, the Western Diamond-backed Rattlesnake peaks from March to October.

Where does the Western Diamond-backed Rattlesnake live?

It has enough records to show in 12 ecoregions and 5 states, including Arizona, California, New Mexico, and Oklahoma.

Is the Western Diamond-backed Rattlesnake venomous?

Yes. The Western Diamond-backed Rattlesnake is venomous. Don't handle it, and give it room.

What snakes get mistaken for the Western Diamond-backed Rattlesnake?

Harmless lookalikes include the Gopher Snake, Pine Snake, and Eastern Hognose Snake.