Binghamton Zoo Animals

Boa Constrictor

(Boa Constrictor constrictor)
Order: Squamata
Family: Boidae
Genus: Constrictor
Species: constrictor

HABITAT AND RANGE: Red-Tailed Boas are from South America, Mexico and Columbia. Ranging from the high cloud forests to the dry low lands, these beautifully marked snakes are only moderately arboreal. They are frequently found near human habitation, due to the abundance of rodents found near human habitats.

PHYSICAL CHARACTERISTICS: The Red-Tailed Boa is very similar to the common Boa Constrictor; however, its tail is a more distinct reddish color. They have pale colors beneath the striking patterns on their skin, typically a soft gray or tan. The name "red-tail" clearly refers to the deep red markings on their tails as well as the red saddle markings along their backs. They are large, hardy, powerful snakes. Specimens from most localities have more or less prominent dark red, reddish brown or brown markings on the tail. A male Red-Tailed Boa tends to be 6 to 8 feet long and very thick bodied. Females will reach closer to 8 to 10 feet and are also thick bodied. Healthy adults usually weigh between 30 and 60 lbs. The largest Boa in captivity is 16 ft. long. Growth is directly related to diet and housing conditions. However, unlike fish, a reptile will outgrow its surroundings.

ADAPTATIONS: Boas are primarily nocturnal or crepuscular (active at dawn and dusk). In the extreme northern and southern portions of their range, the Boas will often go through several weeks of inactivity to get through the periods of extreme cold or drought. When young, they can be aggressive, but become calmer and non-aggressive as they age.

DIET: The Red-Tailed Boa feeds on small mammals, amphibians, lizards, other snakes and birds. Like other boa constrictors, this snake kills its prey by squeezing it with its powerful coils until the victim can no longer breathe. Then it swallows its meal whole, head-first. After eating a large animal, the boa doesn't need to eat again for a long time, and may rests for weeks.

REPRODUCTION AND DEVELOPMENT: Female boas produce live offspring instead of laying eggs. Fertilization by the male is internal. During copulation, males can cling to the female via a small set of "spurs" that are generally hidden below scales on either side of the vent and are actually evolutionary remnants of the hind legs. The gestation period of boas is 108 days after the post ovulation shed. They will give birth to anywhere between 20 and 40 young. At birth red-tailed boas are between 16 and 20 inches long. A hatchling will increase its size by 300% in its first year, reaching 5 to 6 feet in that time. Sexual maturity is reached at 3 years. In captivity, the Red-Tailed Boa can live more than 40 years.

STATUS IN WILD: True Red-Tailed Boas are increasingly rare in the wild. The population is declining due to deforestation, over collection for the skin trade as well as occasional consumption by humans. The pet trade is no longer a major threat to this animal as Boa Constrictors breed readily in captivity.