Bullsnakes in New Mexico

Closeup of a bullsnake in the wild. The bullsnake has a shield on its nose to help it dig.
Greg Birkett/Shutterstock.com

Written by Brandi Allred

Updated: April 8, 2023

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New Mexico is home to an astonishing array of desert-dwelling creatures; of these, reptiles are plentiful. Among New Mexico’s reptiles are 46 species of snake, only eight of which are venomous. But are bullsnakes in New Mexico venomous or harmless? We’ll answer that question, and many more, here. 

Bullsnakes are common in New Mexico, and they can grow to pretty large proportions. These creatures are responsible for controlling a certain pest population and should be left alone if encountered. Here, we’ll explore basic bullsnake safety and whether or not you need to be worried about bites. We’ll also find out if it’s true that bullsnakes keep rattlesnakes away and where exactly in New Mexico these incredible reptilians live.

Profile: The Bullsnake


Known as cincuate in Mexico, bullsnakes have been around for a very long time and are well known to locals.

Bullsnakes are large snakes that vaguely resemble the much more dangerous rattlesnake. They’re not endangered, though they are unfortunately frequently killed by humans who mistake them for rattlesnakes. Like all snakes, bullsnakes are ectotherms. This means that they have no ability to control their own body temperature, which is why they become sluggish with the cold and active after they’ve sunned.


Bullsnakes are a subspecies of gopher snakes. Their base color is light tan or sand-colored. Their bellies are pale and lack markings, while the sides have various light brown to dark-brown small blotches. Bullsnakes’ backs have regularly spaced reticulated brown markings, a little bit like the markings of a giraffe. Their heads, necks, and tails tend to have darker blotches than the rest of their bodies.

Bullsnakes in New Mexico may resemble rattlesnakes, but the best way to tell the two apart is by looking at the head and the tail. Bullsnake tails lack rattles, even though they may shake them in mimicry of rattlesnakes. Their heads are narrow, barely wider than their necks, with small eyes and round pupils. Bullsnakes lack the wide, triangular heads of pit vipers, as well as their large fangs and venom glands.



There are few snakes in North America that grow larger than the bullsnake.

Bullsnakes in New Mexico are heavy-bodied snakes that rely on their musculature to constrict prey to death. They’re among the largest native snakes in North America. The largest bullsnakes grow up to eight feet long and weigh nearly ten pounds. It’s not uncommon for these snakes to reach 5-6 feet in length. Bullsnakes are large, but indigo snakes, and western diamondback rattlesnakes, grow even larger. 


Bullsnakes eat mostly rodents, like rats, mice, voles, ground squirrels, and pocket gophers. Because of this, they’re important pest control agents, particularly in suburban and even urban settings. To hunt, bullsnakes ambush prey, then wrap it up in their coils and squeeze until its struggles cease. Then, they swallow their prize whole. However, if confronted with something bigger and more dangerous than they are, bullsnakes respond in surprising ways.

Are Bullsnakes Dangerous to Humans?

Bullsnake - Coiled

Some of the most deadly snakes in the United States include copperheads and coral snakes, but not bullsnakes.

Often, when bullsnakes in New Mexico encounter predators, like humans, dogs, jackals, or larger snakes, they pretend to be something they’re not. That something is the infamous rattlesnake, which poses a much greater threat than the venomless bullsnake. That’s right: bullsnakes might seem scary, but they actually lack any form of venom and pose zero threat to humans. 

But, when bullsnakes are cornered, they actually try to trick the would-be predator into fearing them. They do this by coiling up into rattlesnake-like balls, hissing, and vibrating their tails. Bullsnakes in New Mexico have no rattles, but that doesn’t stop them from trying to make a rattling sound to ward off would-be attackers. If you see a bullsnake, don’t approach it. Rather, walk around it, and leave it to hunt rodents and other pests.

Do Bullsnakes Keep Rattlesnakes Away?

Many people believe that bullsnakes prey on rattlesnakes.

For years, people have whispered that bullsnakes in New Mexico are good to keep around because they eat rattlesnakes. Therefore, more bullsnakes mean fewer dangerous rattlesnakes. But, is there any truth to this? Well, it depends on who you ask, but scientists are certain of one thing: bullsnakes eat a lot more rodents than they eat rattlesnakes. While no one is really sure whether or not bullsnakes keep rattlesnakes away, you can bet that they decrease local rodent populations. So, if you see a bullsnake around your home, be sure to remember that its presence is actually a good thing. And, that bullsnakes in New Mexico might even keep rattlesnakes away.

Distribution and Habitat

Bullsnakes aren’t just widespread in New Mexico, they’re also common in many parts of the Midwestern United States.

Though not quite as widespread as the copperhead, bullsnakes occupy a large swathe of North America. They can be found in southern Canada, the Great Plains, and the southeastern United States. Additionally, bullsnakes live in the mountainous states of Montana and Colorado, among others. They’ve been found at elevations up to 9,000 feet and in New Mexico, as low as 3,000 feet. 

Bullsnakes are very successful habitat generalists. They thrive in all habitats ranging from dry, sandy deserts to wooded valleys and meadows. They’re especially prevalent in agricultural areas and empty fields and may be found escaping the sun’s heat underneath outbuildings.

Where do Bullsnakes Live in New Mexico?

Bullsnakes in New Mexico live throughout most parts of the state. You’re most likely to encounter them in areas with high rodent populations, such as agricultural fields and disused buildings. They can also slither into unused basements, attics, barns, and sheds. Like all snakes, bullsnakes become less active in the winter and may overwinter in unused rodent burrows or rocky crevices. During the hottest parts of the summer, you’re most likely to see them at dawn and dusk.

Other Snakes in New Mexico

Snake, Fang, Rattlesnake, Poisonous, Aggression Snake, Fang, Rattlesnake, Poisonous, Aggression

Rattlesnakes are pit vipers that use powerful venom to subdue their prey.

Some species of snake are welcomed as neighbors – like the bullsnake, which keeps rodents in check and, many believe, also preys on rattlesnakes. Why are bullsnakes welcomed and rattlesnakes hated? Rattlesnakes are deadly, it’s as simple as that.

Rattlesnakes can be easily identified by the rattles on the end of their tails that serve as fair warning to anyone daring to confront this venomous reptile. Rattlesnakes are pit vipers, meaning that they can track prey using the heat sensors located in the pits on either side of their heads. The powerful venom injected by the snake’s long fangs stops the body’s ability to clot blood and destroys internal tissues – quickly disabling the bitten prey. Believed to have evolved more recently than other snakes, rattlesnakes can control the amount of venom they use when they bite, and as many as 50% of bites are “dry” with no venom at all. 50/50 odds aren’t worth the risk – so you would be advised to give these potentially deadly snakes a wide berth.

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About the Author

Brandi is a professional writer by day and a fiction writer by night. Her nonfiction work focuses on animals, nature, and conservation. She holds degrees in English and Anthropology, and spends her free time writing horror, scifi, and fantasy stories.

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