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Rattlesnake

Lower California Rattlesnake

Venomous

Crotalus enyo

Lower California Rattlesnake
Crotalus enyo, © MarvalPhotography19
Lower California RattlesnakeLower California RattlesnakeLower California RattlesnakeLower California RattlesnakeLower California Rattlesnake

6 photographs of the Lower California Rattlesnake. © MarvalPhotography19.

The Lower California Rattlesnake (Crotalus enyo) is a venomous snake in the Viperidae family, recorded in 2 countries.

If you are bitten

Rattlesnake bites are medically serious. Expect intense pain, rapid swelling, and bruising. Stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to an emergency room immediately. Do NOT apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call Poison Control at 1-800-222-1222 or 911 in the US, or your local emergency number. (Source: CDC.)

Also called
Rattlesnake
Family
Viperidae
Size
Typically 2–5 ft; some species exceed 6 ft.
Habitat
Deserts, rocky outcrops, grasslands, and woodland edges, depending on species.
Behavior
Ambush predators that buzz the tail as a warning; mostly active in warm months and often crepuscular in summer heat.
Identify
Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
Danger
high

About the Lower California Rattlesnake

Crotalus enyo, commonly known as the Baja California rattlesnake or Lower California rattlesnake, is a pit viper species native to the coast and islands of northwestern Mexico. Like all other pit vipers, it is venomous. Three subspecies are currently recognized, including the nominate subspecies described here.

Description

The maximum reported length of this species is 89.8 cm (35.4 in) (Klauber, 1972). It is sexually dimorphic, with the males typically being larger than the females. The head is remarkably small and narrow, while the eyes are proportionately large.

Geographic range

In western Mexico in the north, it is found in the Baja California Peninsula from around Río San Telmo on the west coast and from opposite Isla Angel de la Guarda on the gulf coast, south to Cabo San Lucas. It is also found in the Gulf of California on the islands of San Marcos, Carmen, San José, San Francisco, Partida del Sur, Espírita Santo and Cerralvo. Off the Pacific coast, it is also found on the island of San Margarita. The type locality is "Cape San Lucas, Baja California Sur".

Habitat

It prefers desert, but in the northwestern part of its range, it can be found in chaparral country, while in the cape region (Sierra de San Lázaro), it occurs in pine-oak and tropical deciduous forest. It can be found in rocky areas with arid thorn scrub and cacti, but sometimes also in sand dunes. It is often attracted to human habitation, where it has been found in piles of refuse.

Conservation status

This species is classified as Least Concern on the IUCN Red List (v3.1, 2001). Species are listed as such due to their wide distribution, presumed large population, or because they are unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend was stable when assessed in 2007.

Feeding

Snakes of this species, regardless of their size, are known to eat small rodents, lizards, and centipedes. This is in contrast to many other rattlesnake species that prey on lizards almost exclusively as juveniles, switching to mammals as adults. With C. enyo, small snakes eat lizards more often than do large ones, and large snakes eat mammals more often than do small ones. Adults also prey on large centipedes of the genus Scolopendra.

Reproduction

Captive specimens have produced litters of two to seven young. Newborn specimens with lengths of between 20.6 and 22.2 cm (8.1 and 8.7 in) have been mentioned. Grismer (2002) reported finding neonates in the wild between late July and mid October, which would indicate the species mates in the spring and gives birth in the summer or early fall.

Subspecies

Taxonomy

All three of the current subspecies were recognized by Beaman and Grismer (1994) in their review, but they indicated C. e. furvus should not be considered a separate subspecies, and C. e. cerralvensis would best be considered a full species.

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Lower California Rattlesnake

Is the Lower California Rattlesnake venomous?
Yes. The Lower California Rattlesnake (Crotalus enyo) is venomous and belongs to the Viperidae family (rattlesnake). Its bite is considered high risk to people. Treat any bite as a medical emergency.
Is the Lower California Rattlesnake poisonous?
Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Lower California Rattlesnake is venomous, delivering venom through a bite.
Is the Lower California Rattlesnake dangerous?
Rattlesnake bites are medically serious. Expect intense pain, rapid swelling, and bruising. Stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to an emergency room immediately. Do NOT apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call Poison Control at 1-800-222-1222 or 911 in the US, or your local emergency number. (Source: CDC.)
Where does the Lower California Rattlesnake live?
The Lower California Rattlesnake has verified records in 2 countries, including Mexico, United States of America. See the distribution section below for its full range.
How do I identify the Lower California Rattlesnake?
Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
How big does the Lower California Rattlesnake get?
Typically 2–5 ft; some species exceed 6 ft.
What does the Lower California Rattlesnake eat?
Snakes of this species, regardless of their size, are known to eat small rodents, lizards, and centipedes. This is in contrast to many other rattlesnake species that prey on lizards almost exclusively as juveniles, switching to mammals as adults. With C. enyo, small snakes eat lizards more often than do large ones, and large snakes eat mammals more often than do small ones. Adults also prey on large centipedes of the genus Scolopendra.

If you are bitten by the Lower California Rattlesnake

A venomous snakebite is a medical emergency. Call your local emergency number immediately. In the US, dial 911 or Poison Control at 1-800-222-1222.

Do

  • Get away from the snake and stay calm. Most bites worsen when people panic or try again to handle the snake.
  • Call 911 or Poison Control (1-800-222-1222) right away. Antivenom works best when given early.
  • Note the time of the bite and, from a safe distance, the snake's color and pattern, a phone photo is enough. Do not chase it.
  • Keep the bitten limb still and at roughly heart level. Sit or lie down and limit movement.
  • Remove rings, watches, and tight clothing near the bite before swelling starts.
  • Gently wash the bite with soap and water and cover it with a clean, dry dressing.

Do not

  • Do not cut the wound or try to suck out the venom.
  • Do not apply a tourniquet or ice.
  • Do not drink alcohol or caffeine.
  • Do not take aspirin or ibuprofen, they can worsen bleeding. Acetaminophen is safer for pain.
  • Do not try to catch or kill the snake. A dead snake can still bite by reflex.

First-aid guidance adapted from the U.S. Centers for Disease Control and Prevention (CDC NIOSH), Venomous Snakes. Educational only; always follow the instructions of emergency responders.

Where it is found

MexicoUnited States of America

Snakes it is confused with

More Viperidae snakes

Classification

How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.

OrderThe broad group of scaled reptiles: all snakes and lizards
Squamata
FamilyA group of related snakes that share key traits
Viperidae
GenusA close-knit group of very similar species
Crotalus
SpeciesThis exact snake, named in the two-part scientific name
Crotalus enyo

Keep learning

Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.