The Boa Constrictor and the Pythons are large non-venomous snakes, which kill by constriction. They are popular vivarium reptiles and most species have few problems with captivity as long as a reasonable temperature is maintained. They need a good size of enclosure and as long as the owner is prepared for the size and longevity of the animal they can be a rewarding pet.
This snake originates from Central and South America and can grow to 4 m. (13 feet) on a diet of rodents, chickens and, when larger, rabbits. In the wild boas spend much of their time in trees and thus they need a tall vivarium with plenty of access to branches for climbing. It is an unusual boa which does not take dead prey items with alacrity. Boa constrictors may live up to 40 years. They reach sexual maturity once they become around 1.5 m. (5 ft) in length. Live young are born around 6 months after mating. Right from the start they are able to eat mice and rarely present problems in management as long as steps are taken to mirror their natural environment and tree-climbing habits.
Epicrates cenchria is, as its common name suggests, one of the most colorful of the boids, especially immediately after shedding. The subspecies from Brazil is predominately red while others tend to be more a brown than a red color. Again it originates from Central and South America. Gestation in this breed is about 5 months and newborn babies are around 60 cm (25 in.) long and adults reach up to 2 m (6.5 feet) in length. This species needs a temperature of between 24-30C (75-86F). The diet of the Rainbow boa is predominantly small mammals and birds.
This species, Python molurus, is the classic old world constrictor equivalent of the boa constrictor. It is relatively easy to maintain, the only drawback being its substantial size. While the New World boas grow to around 4.3 m. (13 feet) the pythons may reach up to 6.5 m. (21 feet) long. Their diet should be large rodents, rabbits and chickens but one problem can be overfeeding. A python that is fed on a weekly basis but does not have to hunt for its dinner may eventually result in morbid obesity where the intracoelomic fat body is very large and there is fatty infiltration of the liver and kidneys, precluding normal function. Female pythons will breed, stimulated by a reduction in light and day length. The eggs will be laid approximately 3 months from mating. The female will incubate the eggs for around 70 days until the eggs hatch. The young will molt and after that initial ecdysis will eat. Within 18 months they can be mature.
The Royal python, Python regius, originates in Africa and is also known as the ball python since it readily curls into a ball when threatened. The snake is attractive but is difficult to keep given that long periods of inappetance are more likely than not to be encountered. While mice are a preferred food it is often the case that white laboratory mice appear not to be recognized as a prey item. In such cases a brown gerbil may provoke the animal to break its fast.
Probably the world's longest snake Python reticulatus has a striking series of diamond shaped yellow patches down its back and flanks marked with brown, black, cream and purple. All this makes it a very desirable animal to keep but in fact the snake is, in the words of a trusty author 'irascible and untrustworthy' and as such grows to be 'a most difficult animal to handle safely'. It feeds on larger mammals as well as rodents but while it does not have the anorexic problems of the Royal python, it can be frustratingly difficult to breed in captivity.
There are many other species of python and boa but those noted here are among the easier ones to keep. Snakes like the Reticulated Python can be dangerous and the Royal Python a frustratingly anorexic pet. Perhaps it is better to choose the classic Boa constrictor and the Indian or Burmese python as a first constrictor snake to keep.