8 Types of Venomous Snakes in New Mexico! (ID Guide)
“What kinds of venomous snakes can you find in New Mexico?”
This question is extremely common. Everyone wants to know if any dangerous snakes live near them and what they look like!
Believe it or not, you can find EIGHT types of venomous snakes in New Mexico. But please don’t live in fear, thinking that you are going to be bitten. In general, snakes try to avoid any contact or interaction with people. As long as you leave them alone, you shouldn’t have any trouble!
Did you know that snakes are considered venomous, NOT poisonous? If you eat something that makes you sick, then it’s considered “poisonous.” If an animal, like a snake, delivers its toxins when it bites, then it’s considered “venomous.”
*If you come across any of these species, PLEASE DO NOT DISTURB! Venomous snakes are dangerous animals and should be left alone. The more you agitate them, the more likely you could get bitten. DO NOT RELY ON THIS ARTICLE to correctly identify a snake that has recently bitten you. If you have recently been bitten, GO DIRECTLY to the nearest hospital to get help and to determine if the snake is venomous.*
8 Venomous Snakes That Live in New Mexico:
RELATED: The 27 Types of SNAKES Found in New Mexico! (ID Guide)
#1. Arizona Coral Snake
- Micruroides euryxanthus
- Adults are typically between 11 and 24 inches long.
- Smooth scales with bands of red and black, which are divided by narrower bands of light yellow or white.
- The head is black, and the red bands are typically absent from the tail.
Arizona Coral Snakes, which are also called Sonoran Coral Snakes, can be found in desert scrublands, semi-desert grasslands, rocky canyons, and oak woodlands. Due to their secretive nature and the fact they are nocturnal, these venomous snakes are not often seen.
These snakes rarely harm people in New Mexico, despite being highly venomous.
They are generally considered non-aggressive and have small, fixed fangs that make it difficult for them to deliver venom to larger animals. However, they should still be treated with care if found!
Coral snakes use their toxic venom to immobilize and kill prey. Interestingly, this species feeds primarily on other snakes, with Thread snakes being their most favorite victims. However, they also consume various types of lizards.
You may hear them produce a “popping” sound when threatened or captured, which sounds like they are passing gas. This noise is made by expelling air from their cloaca.
#2. Western Diamond-backed Rattlesnake
- Crotalus atrox
- Adults typically grow to about 4 feet in length.
- Coloration ranges from brown, gray, brick red, pinkish, and chalky white. Look for the darker diamond-shaped blotches down its back, which are outlined by white scales.
- Broad, spade-shaped head with a black mask over the eyes. Elliptical pupils and pits between eyes and nostrils.
- A rattle on the tail alternates between black and white-colored bands.
This famous venomous snake has a wide range of habitats in New Mexico!
You might spot them in deserts, grassy plains, forested areas, rocky hillsides, and river bottoms. But your best chance to see one might be on a rural road in the evening because of the heat the pavement retains.
Western Diamond-backed Rattlesnake Range Map
Western Diamond-backed Rattlesnakes hibernate in communal caves, dens, or rock ledges called hibernacula during the winter. They sometimes share these spaces with snakes of other species and can survive in hibernation for several months without eating.
The Western Diamond-backed feeds on small mammals such as squirrels, chipmunks, gophers, prairie dogs, rabbits, mice, and rats. They will also consume birds that fly within reach. Like other pit vipers, they ambush their prey and track them while the venom takes effect.
When threatened, the Western Diamond-backed will typically stand its ground. They rattle and coil, lifting themselves off the ground to prepare to strike.
If you hear their characteristic rattle, make sure to leave the area slowly! Due to their specialized fang and large venom glands, these snakes can deliver a lot of venom in a single bite! Untreated bites have a mortality rate of 10 – 20%, so make sure to get to the hospital quickly if struck!
These venomous snakes reach sexual maturity at three years of age and mate in the spring after emerging from hibernation. Females give birth to ten to twenty live babies. The young snakes have a high mortality rate, but those that survive may live for 20 years or more!
#3. Rock Rattlesnake
- Crotalus lepidus
- Adults rarely exceed 32 inches in length.
- Robust snake with a tail rattle, elliptical pupils, and a heat-sensing pit between the eyes and nostril.
- Coloration reflects the local environment and is typically gray to green with dark brown or black banding. There may be dark speckles between the bands.
These small venomous snakes inhabit arid habitats in southern New Mexico, including grasslands and mountainous areas up to 9600 feet of elevation. They’re often spotted in rocky outcrops and rocky man-made roads. They will shelter in animal burrows, under rocks, and in or under rotting stumps and logs.
Rock Rattlesnakes are a diurnal species, which means you’re most likely to see them out during daylight hours. However, they’re somewhat secretive and hard to spot due to their excellent camouflage.
Rock Rattlesnakes primarily feed on lizards but will also consume centipedes, small mammals, birds, and other snakes when available. Like other rattlesnakes, they use their venom to subdue their prey before consuming it. The venom can cause swelling, bleeding, extreme pain, and local necrosis in humans.
Unfortunately, these venomous snakes are often seen in the exotic animal trade for their beauty and relatively docile nature. Rock Rattlesnakes are known to be declining and are considered threatened in some parts of their range. Additionally, they are listed as a species of least concern on the ICUN Red List.
#4. Black-tailed Rattlesnake
- Crotalus molossus
- Adults range from 32 to 40 inches in length.
- Coloration is mixtures of yellow, olive green, brown, or black with darker blotches, diamonds, or bands with light edges.
- Elliptical pupils, heat-sensing pits between eye and nostril, and distinctive uniform black or dark gray tail with a rattle.
Black-tailed Rattlesnakes inhabit deserts, grasslands, and rocky mountainous areas. They prefer warm and rocky areas like the sides of canyons and caves where they can easily find shelter. They hibernate in animal burrows or rock crevices during the winter.
In the spring and fall in New Mexico, these venomous snakes are more likely to be seen during the day. As the weather gets hotter in summer, they become more nocturnal to avoid the heat.
Black-tailed Rattlesnakes feed on rodents, other small mammals, birds, and small reptiles. Like other rattlesnakes, they use their hemotoxic venom to subdue prey.
They are generally considered docile venomous snakes, and bites to humans are very rare. They’re believed to be less toxic than other species like the Western Diamondback. However, a bite should still be treated at a hospital!
#5. Mojave Rattlesnake
- Crotalus scutulatus
- Adults range from 2 to 4 feet in length.
- Coloration is green, gray, brown, tan, or yellow with darker diamond or diamond-like markings down the back.
- Heavy-bodied, triangular head, elliptical pupils, heat-sensing pits between the nostrils and eyes, and a black and white banded rattle at the end of the tail.
Sometimes called the Mojave Green, these venomous snakes are generally found in arid habitats. They prefer desert flatland with sparse vegetation, high desert, mountain slopes, grassy plains, Joshua tree woodlands, and scrub brush areas.
Mojave Rattlesnake Range Map
The Mojave Rattlesnake is one of the most venomous snakes in New Mexico!
Their venom contains both neurotoxins that attack the nervous system and hemotoxins that attack the blood. These snakes are ambush predators and use their camouflage to wait unseen for unsuspecting lizards, rodents, toads, and snakes.
Interestingly they are sometimes confronted by California Ground Squirrels. These ground squirrels are resistant to snake venom and adept at dodging strikes. They will defend their pups from the Mojave Rattlesnake with vigor!
When disturbed, these venomous snakes will give the characteristic tail rattle as a warning. Their potent venom means that you should give them distance and respect. If someone is bitten, chances of survival are good so long as medical attention is sought immediately.
#6. Prairie Rattlesnake
- Crotalus viridis
- Adults typically range between 3.3 and 5 feet in length.
- Coloration is highly variable and can be greenish-gray, olive green, greenish-brown, light brown, or yellow. All variations have dark blotches on the body that turn into rings near the tail.
- Broad triangular head, elliptical pupils, heat-sensing pits between the eyes and nostrils, and a tail rattle.
These venomous snakes can be found in New Mexico in open prairies, grasslands, semi-desert shrublands, and forested environments. They can even be found at elevations up to 9500 feet!
The Prairie Rattlesnake hibernates during the winter, often in communal dens. These dens are typically rock crevices, caves, or old mammal burrows. Individual snakes will return to the same den each winter and migrate up to seven miles to their hunting grounds in the spring.
When they feel threatened, these snakes will freeze, trying to use their camouflage to avoid detection. They may also quietly crawl away to cover. If approached, they may coil and rattle their tail as a warning before striking. Their potent venom has both hemotoxic and neurotoxic properties, and although rare, can be fatal to an adult human.
Prairie Rattlesnakes are listed on the ICUN Red List as a species of least concern. However, they are considered threatened and declining in parts of their range. They have faced pressure from habitat fragmentation and hunting.
#7. Western Massasauga
- Sistrurus tergeminus
- Adults range from 14 to 36 inches in length.
- Coloration is gray to light brown with dark brown blotches on the back.
- Thick body, large triangular head, heat-sensing pits between the eyes and nostrils, elliptical pupils, and rattle on the tail.
- Often referred to as the Desert Massasauga.
The Western Massasauga is one of the smallest venomous snakes in the country! They primarily inhabit grassland habitats but can also be found in open sagebrush prairie, rocky hillsides, prairie hillsides, open wetlands, and grassy wetlands.
Western Massasauga Range Map
This venomous snake is secretive and is not often seen in New Mexico.
When detected, they often freeze rather than rattling. However, when they do rattle, Western Massasaugas make a distinctive sound. Their rattle is significantly higher pitched than larger rattlesnakes and has earned this small snake the nickname “buzz tail.”
Though their venom is highly potent, the small quantity they deliver makes their bites much less likely to cause fatality in humans than some larger venomous snakes. However, you still need to respect them as their venom is hemotoxic and will cause localized swelling, extreme pain, and necrosis. Medical attention should be sought immediately if bitten!
#8. Ridge-nosed Rattlesnake
- Crotalus willardi
- Adults are only 12 to 24 inches in length.
- Coloration is typically reddish-brown to yellowish gray and matches the color of leaf litter in its habitat. White or pale horizontal striping on its body.
- Look for two white streaks beneath the eyes, heat-sensing pits between the eyes and nostrils, elliptical pupils, and tail rattle.
These reclusive venomous snakes are typically found in far southwestern New Mexico at mid to high elevations in pine, oak, and juniper woodlands. Their limited mountainous habitat and small size means that sightings are rare.
Ridge-nosed Rattlesnakes are threatened across most of their habitat. Fires, mining, habitat loss from cattle farming, and deforestation are all challenges. In addition, these small snakes have to deal with getting killed and collected by humans.
During the breeding season, males compete hard for mating privileges. They raise their upper bodies, intertwine, and try to press the other male to the ground. Males are opportunistic breeders, but females can be very selective. Courting and mating occur in late summer or early fall from about July to August. Females typically reproduce every second or third year.
Do you need additional help identifying a venomous snake?
I recommend purchasing a Peterson Field Guide to the Reptiles and Amphibians of North America. These books have lots of helpful information, including pictures and range maps. View Cost - Amazon
Which of these venomous snakes have YOU seen in New Mexico?
Leave a comment below!