Nine recognized subspecies of Epicrates cenchria are found from southern Mexico through Central America and throughout most of South America. The Brazilian Rainbow Boa (E. cenchria) is the most commonly kept subspecies in captivity. Its natural range includes the Amazon River Basin from Peru and Brazil to Colombia and northeast to Suriname. They inhabit tropical and subtropical broad-leaved forests described as hot and wet. A steady temperature between 73 and 90 degrees Fahrenheit is expected year round, and annual rainfall varies from 58.5 to 136.5 inches depending on the particular location. Humidity is fairly constant at 60 to 70 percent.
Brazilian rainbows are a popular subspecies because of their outstanding appearance. Males reach sizes of 5½ to 6 feet long. Large females can grow to 6 to 7 feet and weigh up to 9 pounds. They are impressive animals but not giant snakes. They never get so big that one person can’t handle them alone.
The Brazilian Rainbow Boa's color ranges from orange to deep-red with orange to red saddles running down their backs. Each saddle is bordered by black. Usually three distinct black stripes run along their heads, and black circles containing yellow to orange to fiery-red crescent-shaped markings run along each side of the animal’s body from head to tail. These markings contrast their stark-white ventral surfaces, and they are further enhanced by the iridescence radiating from their scales, which reflect hues of blue, green and purple thanks to chemicals called “purines” located in cells of the epidermis.
Brazilian Rainbow Boas are nocturnal, and they often become active an hour or two after sundown. They may be found searching for a drink or for a new daytime hiding spot. Once they have found a suitable location, they assume a sit-and-wait position with their heads extended from their shelters. Rather than actively hunting down their prey, they probably seek out high-rodent-traffic areas. Once such an area is found, they patiently wait for their next meal.
Humidity in the Brazilian Rainbow Boa’s native habitat is high. Although this should be a consideration when keeping these animals in captivity, an exact percentage isn’t critical. Lightly misting babies once a day and letting the water evaporate overnight keeps their sheds in one piece. Their cages are ventilated, so any moisture evaporates over the course of a 24-hour period. Adult cages are sprayed but not on a regular basis. Every few days they get a spritz. However, shedding adults are sprayed down once per day. They seem to be able to take care of much of their own needs for water if provided with a large tub in which to soak. If you live in a very dry climate, you may have to mist more often to keep the humidity up.
Brazilian Rainbow Boas are not difficult to breed in captivity. However, the task requires some patience. Pre-breeding conditioning begins with a nighttime drop in temperature. It is recommended that a cooling cycle begins on November 1 with a nighttime temperature drop to 84 degrees. Every seven days the temperature drops 2 degrees until 68 degrees is reached as a nighttime low. This usually occurs mid-December. During the cooling period, the daytime temperature remains at 85 degrees, and males and females remain separate and are fed normally. A temperature of 68 degrees is held as a nighttime low for three weeks. Then, the nighttime low is gradually increased two degrees per week until it is back to 85 degrees around the end of January or the beginning of February.