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Boa Constrictor
Boa constrictor

Photo: Close-up of a boa constrictor's head
Close-up of a boa constrictor's head
Photograph by Joel Sartore

Boa Constrictor Profile

Boa constrictors wear some of the most distinctive markings of all reptiles. Depending on the habitat they are trying to blend into, their bodies can be tan, green, red, or yellow, and display cryptic patterns of jagged lines, ovals, diamonds, and circles.

Boas are nonpoisonous constrictors found in tropical Central and South America. Like their anaconda cousins, they are excellent swimmers, but prefer to stay on dry land, living primarily in hollow logs and abandoned mammal burrows.

Significantly smaller than anacondas, boas can grow up to 13 feet (4 meters) long and weigh more than 100 pounds (45 kilograms). Their jaws are lined with small, hooked teeth for grabbing and holding prey while they wrap their muscular bodies around their victim, squeezing until it suffocates. Boas will eat almost anything they can catch, including birds, monkeys, and wild pigs. Their jaws can stretch wide to swallow large prey whole.

Female boas incubate eggs inside their bodies and give birth up to 60 live babies. Boas are about 2 feet (0.6 meters) long when they are born and grow continually throughout their 25 to 30-year lifespan. The largest boa constrictor ever found measured 18 feet (5.5 meters).

Hunted for their fine, ornate skin and for sale in the exotic pet trade, some boa constrictors are endangered and most have protected status in their range.

Fast Facts

Type: Reptile
Diet: Carnivore
Average lifespan in the wild: 20 to 30 years
Size: 13 ft (4 m)
Weight: 60 lbs (27 kg)
Group name: Bed or knot
Did you know? Some South Americans keep boas in their houses to control rat infestations.
Size relative to a 6-ft (2-m) man:
Illustration of the animal's relative size

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