This rattlesnake decided to get in a standoff with my Jeep the other day while we were prowling around the outskirts of the El Paso Mountain Wilderness in Kern County. The Northern Mojave Rattlesnake is more commonly known as the Mojave Green because it often is a silver-green color that allows it to blend into the creosote scrubland it inhabits. It is considered to be the most deadly of all pit vipers because its venom contains a neurotoxin in addition to a hemotoxin. The venom of a Mojave Green is estimated to be as much as 16 times more potent than that of the Western Diamondback. Immediate treatment is required if you are bitten, so you don't want to mess around with this snake.
They are also more aggressive than Western Diamondback rattlesnakes (crotalus atrox). While other snakes will usually slither away if you give them a chance (stomping on the ground can help), the Mojave Green tends to prefer to stand its ground. This one refused to budge from the center of the trail for more than 15 minutes despite our remaining a good distance away once we spotted it. The upside is that I had more than enough time to grab a telephoto lens so I could photograph it from a safe distance. We didn't want to take a chance trying to drive over it, so we carefully chose a path around it where we would cause minimal damage to the plants.
The Mojave Green looks similar to the Western Diamondback. If it doesn't have the characteristic green color, the Mojave Green has a light stripe that extends from behind its eye to behind its jaw while on the Western Diamondback the stripe goes from behind the eye to intersect with the jaw, and the Mojave Green has 2 large scales between the supraoculars while the Western Diamondback has multiple scales, and near the tail where the diamonds fade the Mojave Green has narrow black rings that are often offset while the Western Diamondback has broad black and white rings that are fairly equal in width.
My husband had never heard a rattlesnake in the wild before. "That's not how I expected it to sound," he said. It's a buzzing sound, not unlike a large swarm of cicadas. It doesn't sound at all like a "rattle" if that's what you are expecting. You can listen to a Mojave Green rattle here on the California Herps website.
The snakes are out and about on warmer days this time of year, so be careful out there! Wear boots, watch where you're walking, and be especially careful when scrambling on rocks.