B
Species Profile

Bullsnake

Pituophis catenifer sayi

Prairie's loudest look-alike
Greg Birkett/Shutterstock.com
Closeup of a bullsnake in the wild. The bullsnake has a shield on its nose to help it dig.

At a Glance

Wild Species
Also Known As Gopher snake, Gopher, Chicken snake, Rat snake
Diet Carnivore
Activity Diurnal+
Lifespan 10 years
Weight 3.5 lbs
Status Not Evaluated
Did You Know?

Adults are commonly ~120-180 cm total length; the longest published individuals reach about 250+ cm (e.g., summarized in Ernst & Ernst, 2003).

Scientific Classification

The bullsnake (Pituophis catenifer sayi) is a large, nonvenomous colubrid constrictor of central North America, well known for mimicking rattlesnakes by hissing loudly, flattening its head, and vibrating its tail when threatened.

Kingdom
Animalia
Phylum
Chordata
Class
Reptilia
Order
Squamata
Family
Colubridae
Genus
Pituophis
Species
Pituophis catenifer

Distinguishing Features

  • Large, heavy-bodied gopher snake with tan/yellow ground color and bold dark dorsal blotches
  • Round pupils; lacks a true rattle (tail vibration can mimic one in dry leaf litter)
  • Powerful hiss and ‘blown-up’ defensive posture typical of Pituophis
  • Nonvenomous; kills prey by constriction, commonly rodents

Physical Measurements

Length
4 ft 11 in (3 ft 11 in – 8 ft 2 in)
Weight
3 lbs (1 lbs – 8 lbs)
Tail Length
9 in (7 in – 1 ft 3 in)
Top Speed
4 mph
Top speed about 6 km/h

Appearance

Primary Colors
Secondary Colors
Skin Type Dry, tough scales; dorsal scales are strongly keeled and rough. Enlarged ventral scutes aid locomotion. Like other Pituophis, the rostral scale is large and tough for digging in prairie and grassland soils.
Distinctive Features
  • Bullsnake (Pituophis catenifer sayi) is a large, thick-bodied, nonvenomous colubrid constrictor; adults usually 100–180 cm long, with some reported near 254 cm.
  • Defensive rattlesnake mimicry: when threatened, commonly coils, flattens the head/neck, hisses loudly, and vibrates the tail against dry vegetation/substrate; it does not possess a real rattle (not a Crotalus/Sistrurus).
  • High-contrast checkered belly (black on cream/white) is often visible when the snake is agitated or moving over uneven ground.
  • Enlarged rostral ('shovel-like') snout scale suited for burrowing and excavating rodent tunnels-consistent with its prairie/grassland ecology and rodent-eating role.
  • Dorsal keel gives a matte, roughened appearance compared with many smoother-scaled colubrids; overall look is "bull-necked" and heavy for its length.

Sexual Dimorphism

Sex differences in the bullsnake (Pituophis catenifer sayi) are slight and mostly about shape, not color. Males usually have longer tails and a bulge at the tail base; females tend to be heavier at the same total length.

  • Relatively longer tail compared with females (a common snake dimorphism), sometimes with a slightly thicker tail base due to hemipenes.
  • Often (as in many colubrids) a higher subcaudal count than females; sexing is typically confirmed by probing/popping rather than appearance alone.
  • Often relatively shorter tail and a more gradually tapering tail base compared with males.
  • Frequently more heavy-bodied at equivalent lengths, especially when gravid; coloration/pattern generally overlaps extensively with males.

Did You Know?

Adults are commonly ~120-180 cm total length; the longest published individuals reach about 250+ cm (e.g., summarized in Ernst & Ernst, 2003).

Its defensive "rattlesnake act" can include explosive hissing, head-flattening, S-coiling, and rapid tail vibration in dry grass.

Bullsnakes have a specialized laryngeal structure that amplifies their hiss (often described as an enlarged/modified epiglottis in Pituophis; Ernst & Ernst, 2003).

They are powerful constrictors that frequently take pocket gophers, ground squirrels, mice, and rats-making them important natural pest control on prairies and farms.

They often use and enlarge mammal burrows; the stout, slightly upturned snout helps them dig and push through loose soil.

In captivity, Pituophis catenifer commonly live 15-20+ years; wild longevity is typically shorter due to predation and hazards (range often reported around ~10-15 years in field summaries).

Unique Adaptations

  • Hiss amplifier: a modified glottis/epiglottal region in Pituophis produces an unusually loud, harsh hiss-key to its defensive mimicry (Ernst & Ernst, 2003).
  • Rattlesnake-mimic toolkit: tail vibration + bluff strikes + head/neck flattening increases perceived danger without venom.
  • Digging-capable head shape: a robust skull and slightly upturned rostral area help it push through soil and exploit burrow systems.
  • Prairie camouflage: bold dorsal blotches and a yellow/tan ground color break up the body outline in grasses, sandy soils, and shrub-steppe mosaics.
  • High jaw mobility and recurved teeth: supports handling of bulky prey (e.g., ground squirrels) typical of open-country habitats.

Interesting Behaviors

  • Rattlesnake mimicry display: inflates the body, flattens the head/neck, hisses forcefully, strikes without venom, and vibrates the tail against vegetation or debris.
  • Burrow association: routinely shelters in rodent burrows; will actively search for prey underground and may plug into tunnel systems.
  • Seasonal activity: in the Great Plains, activity peaks in warmer months; individuals brumate (overwinter) in subterranean refuges.
  • Constrict-and-swallow feeding: seizes prey with rearward-curving teeth, coils to subdue, then repositions prey for head-first swallowing.
  • Thermoregulation: alternates between basking in open prairie edges and retreating to burrows/cover to avoid overheating and predators.
  • Reproduction (typical for the subspecies in its range): mating often occurs in spring after emergence; females lay a single clutch of roughly 3-24 eggs in early summer; incubation commonly ~60-80 days depending on temperature (values widely reported across Pituophis catenifer accounts).

Cultural Significance

On the Great Plains, the bullsnake (Pituophis catenifer sayi), often called gopher snake, is seen as helpful by farmers for eating rodents and protecting crops. Its rattlesnake-like act and loud hiss cause misidentification and local stories.

Myths & Legends

A Midwest and Plains tale says the big bullsnake (Pituophis catenifer sayi), also called gopher snake, sneaks into barns at night to drink cow's milk, sometimes with its tail around the udder.

"It can charm livestock" folklore: tales describe a snake "mesmerizing" a calf or cow, leaving the animal oddly calm while the snake feeds (often paired with the barn-milk narrative).

"Chasing snake" stories: people recount bullsnakes "running down" or "chasing" humans in open fields-often linked to the snake's habit of holding ground, bluffing, and moving defensively when cornered on prairie paths.

"Rattlesnake's mate" tradition: in some local storytelling, a bullsnake/gopher snake is described as being paired with rattlesnakes or even acting as their companion-reflecting how closely its display resembles a rattler when threatened.

Name-origin anecdote: early settlers and many later field naturalists noted the bull-like bellowing hiss, which contributed to the common name "bullsnake" and a reputation for being far more dangerous than its nonvenomous nature implies.

Conservation Status

NE Not Evaluated (subspecies not separately assessed by IUCN; species Pituophis catenifer is assessed as Least Concern)

Has not yet been evaluated against the criteria.

Population Unknown

Protected Under

  • IUCN Red List: Pituophis catenifer (species-level) assessed as Least Concern (subspecies P. c. sayi not separately assessed).
  • Canada: Species at Risk Act (SARA) - Bullsnake (Pituophis catenifer sayi) listed as Special Concern at the federal level (prairie Canadian population context); protections and recovery/management planning apply under SARA framework.
  • Canada: COSEWIC has assessed Bullsnake as Special Concern (designatable unit approach in Canada).
  • United States: not listed under the U.S. Endangered Species Act; protection/collection rules vary by state (some states protect native reptiles or regulate take).
  • Subnational: additional protections may occur under provincial/state wildlife acts and regulations (e.g., general prohibitions on killing or collection in some jurisdictions), but coverage is not uniform across the subspecies' range.

Life Cycle

Birth 12 hatchlings
Lifespan 10 years

Lifespan

In the Wild
5–15 years
In Captivity
10–30 years

Reproduction

Mating System Polygynandry
Social Structure Solitary
Breeding Pattern Transient
Fertilization Internal Fertilization
Birth Type Internal_fertilization

Bullsnake (Pituophis catenifer sayi) adults mate in spring after leaving winter sites. Both sexes may mate with multiple partners; males fight. Fertilization is internal, females lay eggs (3–24). No pair bond or parental care; hatchlings are independent.

Behavior & Ecology

Social Aggregation Group: 1
Activity Diurnal, Crepuscular, Nocturnal
Diet Carnivore pocket gophers (Geomys spp.)
Seasonal Hibernates

Temperament

Generally non-aggressive toward humans; prefers escape/avoidance when given cover, consistent with a wide-ranging, fossorially-inclined forager (Ernst & Ernst, 2003).
Bullsnake (Pituophis catenifer sayi) shows defensive bluffing when threatened: loud hissing, flattening head/neck, inflating front body, closed-mouth strikes, and tail vibration that mimics rattlesnakes.
Bullsnakes are mostly active by day in mild weather, but in hot times they are active at dawn and dusk or sometimes at night; temperature, season, and shelter cause this across central North America.
Ontogenetic variation commonly reported in colubrids and noted in field accounts: juveniles/subadults often exhibit higher defensiveness than large adults when handled or closely approached, though individual temperament varies (Ernst & Ernst, 2003).

Communication

Defensive hiss Audible broadband exhalation), often prolonged and repeated during threat displays; produced via forced expiration through the glottis and associated structures (overview in Greene, 1997; species-level natural history in Ernst & Ernst, 2003
Chemical communication via tongue-flicking and vomeronasal Jacobson's organ) sampling of scent trails; used for prey detection and mate tracking (general snake mechanism; discussed in Greene, 1997 and applied broadly to colubrids including bullsnakes
Pheromonal cues in reproduction: males follow female scent trails and engage in close-contact courtship; contact-based chemosensory assessment occurs during mate searching and courtship Ernst & Ernst, 2003
Tactile communication during courtship/mating: body alignment, cloacal apposition, and sustained contact typical of colubrid copulation; not a group-coordinating signal but a direct-contact reproductive behavior Ernst & Ernst, 2003
Visual/postural threat signaling: head/neck flattening, S-coiling, body inflation, and elevation of the forebody; these displays function as deterrent signals to predators Greene, 1997
Substrate-borne signaling component of defense: tail vibration against dry vegetation/leaf litter to create an audible buzz-like sound Greene, 1997; Ernst & Ernst, 2003

Habitat

Biomes:
Temperate Grassland Temperate Forest Desert Hot Desert Cold
Terrain:
Plains Hilly Plateau Valley Riverine Sandy Rocky +1
Elevation: Up to 8858 ft 3 in

Ecological Role

Mid-level terrestrial predator in grassland-prairie-agricultural mosaics; a key rodent-specialist that links small-mammal production to higher trophic levels (as both predator and prey).

Rodent population suppression (notably burrowing/fossorial rodents such as pocket gophers), which can reduce crop and rangeland damage Potential indirect reduction of rodent-borne disease risk by lowering local rodent abundance Energy transfer to higher predators (raptors, carnivorous mammals) that prey on bullsnakes

Diet Details

Main Prey:
Pocket gophers Mice Voles Rat Ground squirrels Prairie dog Cottontails Ground-nesting birds Bird eggs Lizards +4

Human Interaction

Domestication Status

Wild

Bullsnake (Pituophis catenifer sayi) is a wild, non-domesticated North American snake. People have bred them in captivity for pets for decades, making color and pattern varieties, but this is selective breeding, not true domestication. They hiss and mimic rattlesnakes, often leading to them being killed; they help control rodents and face roadkill and habitat loss.

Danger Level

Low
  • Bite risk: nonvenomous; bites can cause puncture wounds and localized pain/bleeding, especially from large adults, but are not medically dangerous in the way venomous bites are.
  • Zoonotic risk: like other reptiles, can carry Salmonella; human infection risk is mitigated by hand hygiene and proper enclosure sanitation (standard public health guidance for reptiles).
  • Defensive behavior: loud hissing, striking, head flattening, and tail vibration can provoke fear and lead to unsafe human reactions (attempted killing/handling).
  • Conservation/human safety crossover: frequent misidentification as rattlesnakes increases intentional killing and harassment; risk to humans is primarily from mishandling or panic rather than from the snake itself (Ernst & Ernst, 2003; Stebbins, 2003).

As a Pet

Suitable as Pet

Legality: Bullsnake (Pituophis catenifer sayi) is often legal as a captive-bred pet in many U.S. areas, but rules vary. Some places limit native wildlife, need permits, or ban capture and transport. Check local laws.

Care Level: Moderate

Purchase Cost: $50 - $250
Lifetime Cost: $1,500 - $6,000

Economic Value

Uses:
Pet trade (captive breeding/retail) Agricultural/ecosystem service (rodent control) Education and outreach (nature centers, classrooms) Scientific research (ecology, behavior, physiology)
Products:
  • live animals (captive-bred pets)
  • educational programming/animal ambassador use
  • non-market pest control value via predation on rodents

Relationships

Predators 9

Red-tailed hawk Buteo jamaicensis
Swainson's hawk
Swainson's hawk Buteo swainsoni
Golden eagle
Golden eagle Aquila chrysaetos
Great horned owl Bubo virginianus
Coyote
Coyote Canis latrans
American badger Taxidea taxus
Red fox
Red fox Vulpes vulpes
Striped skunk Mephitis mephitis
Prairie kingsnake Lampropeltis calligaster

Related Species 11

Gopher snake
Gopher snake Pituophis catenifer Shared Species
Pacific gopher snake Pituophis catenifer catenifer Shared Species
Sonoran gopher snake Pituophis catenifer affinis Shared Species
Great Basin gopher snake Pituophis catenifer deserticola Shared Species
San Diego gopher snake Pituophis catenifer annectens Shared Species
Pine snake
Pine snake Pituophis melanoleucus Shared Genus
Louisiana pine snake Pituophis ruthveni Shared Genus
Baja California gopher snake Pituophis vertebralis Shared Genus
Coachwhip
Coachwhip Masticophis flagellum Shared Family
Great Plains ratsnake
Great Plains ratsnake Pantherophis emoryi Shared Family
Prairie kingsnake Lampropeltis calligaster Shared Family

Ecological Equivalents 5

Animals that fill a similar ecological role in their ecosystem

Prairie rattlesnake
Prairie rattlesnake Crotalus viridis Strong niche overlap in Great Plains/open prairies and rodent-rich habitats. Bullsnakes are well known for rattlesnake mimicry (loud hissing, head/neck flattening, tail vibration), which can cause misidentification in the field where C. viridis is also common.
Great Plains ratsnake
Great Plains ratsnake Pantherophis emoryi Occupies a similar role as a nonvenomous, mid-to-large colubrid predator of small mammals and birds; frequently uses rodent burrows and field edges. Its range overlaps broadly with bullsnakes across parts of the central U.S.
Coachwhip
Coachwhip Masticophis flagellum Shares open-country habitats (prairie, scrub, grassland ecotones) and preys heavily on small vertebrates. Both are diurnally active predators in warm seasons, though coachwhips rely more on speed while bullsnakes rely more on ambush/burrow hunting and constriction.
Prairie kingsnake Lampropeltis calligaster Occurs in grassland and agricultural mosaic habitats and targets similar prey (rodents, small birds, and reptile eggs/young). Prairie kingsnakes can also be intraguild predators of other snakes, creating both niche overlap and potential predation pressure.
American badger Taxidea taxus Both species are strongly associated with burrow systems in prairie and rangeland landscapes: badgers excavate small-mammal burrows that bullsnakes frequently exploit for hunting and refuge, and badgers can also prey on large snakes encountered underground or at den entrances.

A Bullsnake is considered “The farmer’s friend.”

This big snake is one of the largest found in North America, especially in the United States and Canada. Though it can be a bit fractious if it feels cornered, it is welcome on farms because it eats mice, rats, and other vermin. Though it doesn’t eat rattlesnakes as often as it’s rumored to do so, the bullsnake does take them once in a great while, too.

Four Amazing Bullsnake Facts!

Here are four amazing facts about the bullsnake.

  • Males are larger than females, which is unusual for snakes.
  • The bullsnake is a subspecies of the gopher snake.
  • It gets its name because it makes a sound like a bull snorting.
  • It spends most of its day in a burrow and has a shield on its nose to help it dig.
bullsnake

Bullsnakes can be found all across North America and into Mexico.

Where To Find the Bullsnake 

Bullsnakes are found all over North America, from Canada to Mexico. Indeed, in Mexico, it is called the cincuate. It shelters in abandoned gopher burrows in habitats such as grasslands, farms, and open areas.

Scientific Name

The bullsnake’s scientific name is Pituophis catenifer sayi. Pituophis comes from the Greek for “pine” which is pitys and the Greek word for “serpent,” which is ophis. Catenifer is Latin and means “chain-bearing.” This refers to the pattern on the snake’s body. Sayi comes from Thomas Say, who was an American naturalist.

Haasiophis terrasanctus
Haasiophis terrasanctus, found in Israel, is one of the first “true” snakes and still has hind legs.

Evolution

Fossil records show that snakes first appeared during the Cretaceous period — although often retained their hind limbs. The earliest true snake fossils come from the marine simoliophiids, the oldest being hassiophis terasanctus, dated between 112 and 94 million years ago.

Scientists believe that snakes descended from lizards. Pythons and boas, the most primitive snakes, have vestigial hind limbs and some have remnants of a pelvic girdle, appearing as horny projections.

Many modern snakes originated during the Paleocene, alongside the radiation of mammals that occurred after the extinction of non-avian dinosaurs. The expansion of grasslands in North America led to a major radiation of snakes. During the Miocene, the number of snake species increased with the first vipers and elapids and the diversification of Colubridae.

Different Types of Bullsnake

Beautiful specimen of an albino bullsnake hiding in grass. Albino snakes have paler colorations than regular bullsnakes.

Albino bullsnakes have paler colorations than regular bullsnakes.

The bullsnake is a subspecies of the gopher snake and has become a popular pet. Breeders have developed several color morphs including ghost, white-sided, leucistic, Axanthic, red, hypo, and patternless. There are also albino and snow bullsnakes. Albino snakes have paler colorations than regular bullsnakes, while snow bullsnakes are almost completely white. If any patterns show, they are very faint.

Population & Conservation Status 

Scientists don’t know the exact population of these snakes. However, as a subspecies of P. catenifer, the bullsnake’s population is stable and its conservation status is the least concern.

How To Identify Bullsnake: Appearance and Description 

The Bullsnake is similar to the Western Rattlesnake. It has black, brown, reddish or white dorsal blotches on a yellow, cream-colored or beige ground.

The Bullsnake is similar to the Western Rattlesnake in appearance with black, brown, reddish, or white dorsal blotches on yellow, cream-colored, or beige background.

A grown bullsnake is large in size, with a length of as much as 8 feet and a robust body that’s unusual for a member of the usually sleek colubrid family. It usually weighs between 2.2 and 3.3 pounds, though individuals have been found that weigh close to 10 pounds.

Another thing that’s unusual about this nonvenomous snake is that males tend to grow larger than females. A wild bullsnake has black, brown, reddish, or white dorsal blotches on a yellow, cream-colored, or beige ground. The snake usually has spots on its sides, though the sides of some morphs are white. This color pattern makes it resemble a rattlesnake. Baby snakes are gray until their first molt.

The snake doesn’t exactly hibernate but goes dormant during the fall or when food is scarce. It’ll go dormant in a burrow in October and emerge in April — the start of the mating season in some of its range. During its dormancy, it is not unusual to find this otherwise solitary snake with garter snakes, milk snakes, other bullsnakes, or even timber rattlesnakes.

When threatened, the Bullsnake rears up in an S-shape, hisses and vibrates its tail to mimic the venomous rattlesnake.

When threatened, the Bullsnake rears up in an S-shape, hisses, and vibrates its tail to mimic the venomous rattlesnake.

How Dangerous Are Bullsnakes?

Bullsnakes are only dangerous to prey — they aren’t venomous, but their bite can be painful. Some individuals are docile and can be handled, but others will defend themselves with a threatening posture followed by a bite. When faced with a large potential predator that it can’t quickly escape from, the snake rears up in an S-shape, hisses, and vibrates its tail to mimic the venomous rattlesnake. It may lunge and bite even as it tries to slide away.

Behavior and Humans

A coiled light brown with darker markings bullsnake in a natural setting of long golden grass.

Bullsnakes are active during the day and tend to rest at night in old gopher burrows.

Outside of the mating season, these snakes are solitary and spend most of their time resting in old gopher burrows. They prefer open habitats with loose soil. Bullsnakes are active during the day and kill their prey through constriction. They usually take rodents such as mice and rats, but they’re good climbers and have been seen raiding nests for eggs and baby birds.

The snakes’ breeding season begins in March or April, and the female lays her eggs from April to June, depending on where she lives. She usually lays about a dozen eggs in a sheltered area and then leaves them. The baby snakes hatch sometime in August. The lifespan of the snake ranges from 12 to as many as 30 years. Longer life is seen in snakes that are given good care in captivity.

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Sources

  1. Kidadl / Accessed March 1, 2022
  2. Wikipedia / Accessed March 1, 2022
  3. ITIS / Accessed March 1, 2022
  4. The Pithuophis Page / Accessed March 1, 2022
  5. IUCN Redlist / Accessed March 1, 2022
  6. Britannica / Accessed March 1, 2022
  7. Weebly / Accessed March 1, 2022
Lisha Pace

About the Author

Lisha Pace

After a career of working to provide opportunities for local communities to experience and create art, I am enjoying having time to write about two of my favorite things - nature and animals. Half of my life is spent outdoors, usually with my husband and sweet little fourteen year old dog. We love to take walks by the lake and take photos of the animals we meet including: otters, ospreys, Canadian geese, ducks and nesting bald eagles. I also enjoy reading, discovering books to add to my library, collecting and playing vinyl, and listening to my son's music.

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Bullsnake FAQs (Frequently Asked Questions)

Bullsnakes aren’t venomous.