A western diamondback rattlesnake lying coiled up, with the rattle visible
With spring comes warmth and greenery, but it also welcomes some of the deadliest rattlesnakes in ... More
Across much of the United States, spring marks the peak season for snake activity — especially for venomous rattlesnakes you’d be wise to avoid. They spent the colder months tucked away in burrows or beneath rocky outcrops, waiting for the inevitable warmth of spring to arrive.
Now, with rising temperatures signaling the start of mating season and the return of prey, snakes are back on the move — and encounters with humans become far more likely.
In fact, with every 1°C increase in temperature, the odds of a venomous snakebite rise by 5.6%, according to a July 2023 study published in GeoHealth. And in the U.S., those bites are overwhelmingly from rattlesnakes.
Whether you’re hiking desert trails in Arizona, gardening in Florida or just walking your dog through tall grass in Texas, rattlesnake encounters are a real and seasonal risk. Most bites aren’t fatal, but they can be serious, and a couple of species stand out for their potency, proximity to people and reputation.
1. Western Diamondback Rattlesnake
In the deserts and suburbs of the American Southwest, one snake is responsible for more domestic run-ins with humans than any other — the western diamondback rattlesnake, or Crotalus atrox.
Easily recognized by its distinct diamond-shaped dorsal markings and alternating black-and-white “coontail,” this stout-bodied rattlesnake is well adapted to the arid grasslands, rocky hillsides and urban edges of Arizona, New Mexico, Texas and beyond.
MORE FOR YOU
Trump Imposes Tariffs On Uninhabited Heard And McDonald Islands—‘Remotest Places On Earth’
NYT Mini Today: Hints, Clues And Answers For Thursday, April 3
4 Republicans Break With Trump As Senate Rejects His Canada Tariffs
Western diamondback rattlesnake. Notice the markings on its back and the black and white "coontail"
Getty Images
Unlike its eastern cousin — the eastern diamondback rattlesnake, which holds the title for size — the western diamondback is smaller on average. However, this rattlesnake is also more widespread and more likely to be found near homes, hiking trails and roadways.
During spring and fall, it tends to be active in daylight, while in the heat of summer, it becomes nocturnal, often emerging after dark when temperatures drop. Roads and shaded patios can serve as unexpected resting spots.
Its venom is primarily hemotoxic, causing abdominal pain, swelling and potentially serious tissue damage. The venom also contains hemorrhagic toxins which can cause severe internal bleeding and skeletal muscle damage.
Though less toxic than some rattlesnake species, its relatively large venom yield and readiness to stand its ground when threatened make it a serious medical concern. Immediate medical attention is critical if bitten. Symptoms from the bite can escalate quickly, and untreated bites may become life-threatening within hours.
Known for its distinctive rattle, the western diamondback typically warns before striking. But it’s also one of the more defensive rattlesnake species and is less likely to retreat than some of its cousins. When cornered, it will hold its ground, coil and strike if it feels threatened. Encounters can happen suddenly, especially in shaded areas near homes or on sun-warmed roads and trails.
2. Mojave Rattlesnake
Among the rattlesnakes of the Southwest, the Mojave rattlesnake, or Crotalus scutulatus, stands apart for more than its pale greenish hue. Depending on where you find it, this species may carry one of two wildly different venoms.
One is a neurotoxic cocktail that can cause paralysis, and the other is a hemotoxic blend that destroys tissue and blood vessels. In rare cases, it carries both.
You’ll most likely find the Mojave in arid, open terrain across southern California, Arizona, New Mexico, Texas and parts of Nevada and Utah. While it tends to avoid dense vegetation, it’s been spotted near ranches, roadsides and even residential areas that border desert scrub.
It resembles the western diamondback rattlesnake, but can often be distinguished by a slimmer frame, a greenish tint and less distinctly defined tail bands. The light stripe behind its eye typically angles upward, not down to the mouth.
The Mojave rattlesnake can sometimes be mistaken for the western diamondback. However, the Mojave ... More
getty
The Mojave rattlesnake is actually quite shy and more likely to flee, but it will strike decisively when surprised or cornered. Its bites are rare, but medically serious, especially in areas where neurotoxic venom predominates.
The neurotoxic venom can impair nerve signaling, leading to progressive weakness and potentially respiratory failure. Hemotoxic variants, by contrast, cause intense pain, swelling and widespread tissue damage. Hybrid venoms may unleash both effects simultaneously, complicating treatment and increasing risk.
Regardless of the type of venom involved, every bite from a Mojave rattlesnake must be promptly treated, as respiratory symptoms may develop even in the absence of major swelling or pain.
Venomous snakes like these might inspire awe in some and terror in others. Take a 2-minute test to see where you stand on theFear of Animals Scale.
Editorial StandardsForbes Accolades
Join The Conversation
Comments
0
One Community. Many Voices. Create a free account to share your thoughts.
Read our community guidelines .