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Boa Constrictor

Boa Constrictor


Order: Squamata

Family: Boidae

Genus/species: Boa constrictor


Boa constrictors are pinkish or tan in color, with dark crossbands.Typically, they range in lengths from 20 inches (50 cm) as neonates to 13 feet (3.9 m) as adults. Larger members of the Boidae family have heat-sensitive pits on its head, but this snake has more simple heat-sensitive scales. These snakes are solitary and nocturnal.

Distribution and Habitat

Boa constrictors are found from northern Mexico to Argentina.

Of all the boas, this snake thrives in the most varied habitats. It shows, however, the least inclination toward water. It lives in deserts, wet tropical forests, open savanna, and cultivated fields, and from sea level to moderate elevation. Boa constrictors are both terrestrial and arboreal.

Diet in the Wild

This snake feeds on large lizards, small or moderate-sized birds, opossums, bats, mongooses, rats, and squirrels. It is a nocturnal hunter and uses its heat-sensitive scales to locate its prey. The boa constrictor’s preferred prey is bats, which they catch by hanging from the branches of trees or the mouths of caves, grabbing them out of the air as they fly by, and killing them by constriction.

Zoo Diet

The boa constrictor is fed mice, rats, and chicks.


These snakes are seasonal breeders. The female emits a scent from the cloaca to attract males. The male and female join together at the cloaca in order for the male to fertilize the eggs. Fertilization is internal. Females give birth to live young.

Life Span



The boa constrictor is listed on CITES Appendix II, except for B.c.occidentalis, which is list on Appendix I. In many parts of tropical America, boa constrictors are valued as destroyers of rodents. In some areas, these snakes have been “domesticated” for this reason. Many are bred or captured for the pet trade. Thousands of dollars are made importing them to the United States.

Source of Information

All or part of this information was provided by the Animal Diversity Web and Museum of Zoology of the University of Michigan.

It appears here with their permission. The original author of this information was Antonio Garza.

For more information, including references, see the Animal Diversity Web account for this species, here:

http://animaldiversity.ummz.umich.edu/ site/ accounts/ information/ Boa_constrictor.html.