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A patterned boa constrictor draped over a branch.
Photo: Charles J. Sharp, CC BY-SA 4.0, via Wikimedia Commons

Boa Constrictor

Boa constrictor

A large, nonvenomous snake of Central and South America, also called the red-tailed boa, that squeezes its prey.

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About the Boa Constrictor

Boa constrictors live from northern Mexico to Argentina, in deserts, rainforests, savannas and farm fields. Newborns are about 20 inches long, and adults can reach 13 feet and over 100 pounds. Their tan, green, red or yellow bodies have patterns that help them hide. They eat lizards, birds, opossums, bats, rats and squirrels, and hunt mostly at night.[1]

Quick facts

Scientific name
Boa constrictor[1]
Size
About 20 inches at birth; up to 13 feet as adults.[1]
Weight
Over 100 pounds when full grown.[1]
Lifespan
20 to 30 years in the wild.[1]
Diet
Carnivore. Lizards, birds, opossums, bats, mongooses, rats and squirrels.[1]
Habitat
Deserts, wet tropical forests, open savannas and farm fields.[1]
Where it lives
Northern Mexico to Argentina.[1]
Group life
Solitary. Hunts at night.[1]
Babies
10 to 64 live young, average 25.[1]
Conservation status
Least Concern (IUCN Red List, assessed 2014).[2]

Fun facts

  • Boas stop their prey's blood flow instead of crushing it.[1]
  • Some families in South America keep boas at home to catch rats.[1]
  • Boa constrictors can swim but prefer to stay on land.[1]

Vocabulary

constrictor
A snake that kills prey by wrapping around it and squeezing.
nonvenomous
Not able to inject poison.
ambush predator
A hunter that hides and waits for prey to come close.
neonate
A newborn animal.
nocturnal
Active mainly at night.

See it in person

Sources

  1. [1] Smithsonian's National Zoo & Conservation Biology Institute. “Boa constrictor.” https://nationalzoo.si.edu/animals/boa-constrictor (accessed 2026-10-02)
  2. [2] IUCN Red List of Threatened Species. “Boa constrictor (Boa Constrictor).” https://www.iucnredlist.org/species/197462/2486405 (accessed 2026-10-02)

Facts last checked 2026-10-02.

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