Western Diamondback Rattlesnake
Crotalus atrox
The most commonly encountered rattlesnake across the desert Southwest, and the snake most people picture when they hear the word “rattlesnake.” Here is how to identify one, exactly where it lives, and what its bite actually means.
How to Recognize a Western Diamondback
Adults typically run 3–7 ft in length and weigh 2.6–14.8 lb, making this one of the largest and heaviest-bodied rattlesnakes most people will encounter in the field.
The "Coon Tail" Bands
The single most reliable ID feature: bold, high-contrast black-and-white bands immediately before the rattle, roughly equal in width. No other widely distributed US rattlesnake shares this exact pattern.
Diamond Pattern
Dark diamond-shaped blotches down the back with pale, lighter borders. Coloration underneath varies by region — tan, gray, brown, pink, or pale blue depending on local soil and rock color.
Heavy, Plump Build
A stocky, heavy-bodied snake with a short tail and a broad triangular head — noticeably thicker-bodied than a Timber Rattlesnake of similar length.
Easily confused with: the Mojave Rattlesnake, which has a very similar diamond pattern. The tail bands are the tell: on a Western Diamondback the black and white bands are roughly equal width, while on a Mojave the white bands are noticeably wider than the black.
Where It Lives
Confirmed across Texas, Oklahoma, Arkansas, New Mexico, Arizona, Nevada, and California, extending south through most of northern Mexico. It is the most commonly encountered rattlesnake in the Phoenix metro area specifically, and one of the most frequently seen venomous snakes anywhere in its range.
Habitat runs from sea level up to about 7,000 ft elevation — hillsides, rocky canyons, desert scrub, and grassland desert. It shelters in rock crevices and abandoned rodent burrows, and in colder parts of its range dens communally with other snakes through winter.
Why It Matters
Venom Delivery
The Western Diamondback has larger venom glands than many other US pit vipers and can deliver a substantial volume of venom in a single bite. Untreated bite fatality is estimated at 10–20%, though prompt antivenom treatment dramatically improves outcomes and most US bites today are treated successfully.
Defensive, Not Aggressive
Given distance, a Western Diamondback will typically coil, rattle, and hold its ground rather than strike first — the rattle exists specifically to warn you off before contact becomes necessary. Most bites occur when a snake is stepped on, handled, or cornered with no room to retreat.
Why the rest of BSG says “no manufacturer publishes a stop-rate percentage”
A large snake with large venom glands is exactly why fit and material thickness matter more than any marketing number when choosing protection.
Common Questions
Look at the tail bands. On a Western Diamondback the black and white bands right before the rattle are roughly equal width. On a Mojave, the white bands are noticeably wider than the black. Both species share a similar diamond pattern, so the tail is the more reliable tell.
Heading Into Western Diamondback Country?
A large, heavy-bodied rattlesnake with a substantial venom yield deserves real protection, not a marketing claim.
Complete Buying Guide
What manufacturers actually publish, by material.
Back to Rattlesnake Hub
Strike range, ID basics, and the other major species.