Boa Constrictor
Boa constrictor constrictor

CLASS: Reptilia
ORDER: Squamata
FAMILY: Boidae

Average length 9 - 10 feet but can reach 18 feet

Southern Mexico to Argentina

Lives in trees and on ground in rainforests; can swim also

Wild - Small mammals, rodents, birds
Zoo - Mostly rats, sometimes small rabbit or squirrel


  • Camouflaged for protection; No outer ear -- picks up vibrations; Far eyesight; no eyelid, only scale called spectacle over eye.

  • Tongue is used for combined sense of smell and taste. Tongue (Jacobson's organ) does the same work as our nose when we draw air into it.

  • Bites to catch prey and constricts to hold and kill it; swallows it whole, head first. Teeth point toward back of mouth; used to hold prey and guide it down throat; teeth not used for chewing.
  • Well-developed lungs, breathes air
  • Scales cannot be pulled off; each one is a fold of skin and is part of the entire snake's skin; scales on under side of snake are designed for traction and helping snake crawl and climb and are called scutes.


  • Non-venomous; but could have serious bite. Cold-blooded adapts to air or water temperature surrounding it. Boas have vestiges of hind legs or hip bones near end of tail (not usually visible).
  • No two boas have same color patterns -- like our fingerprints.
  • Snakes shed skin because they are growing; number of times skin is shed depends on food supply; young snakes shed more often than adults; pigment is under many layers of skin and is not shed.
  • Many types of boas ranging from SW Asia to South America as well as the Western U.S., Africa, Madagascar, Fiji, Solomon & New Guinea.

Snakes have an important role in nature. They keep the number of rodents under control as well as other animals such as frogs.

Born alive (ovoviviparous -- after fertilization, the eggs remain in the female body until babies are developed.) Up to 30 babies.

CITES App. II; To be added to the endangered species list because of loss of habitat and being killed for their skins.