Brazilian Rainbow Boa Care Sheet

Maria Zayas, DVM
By Maria Zayas, DVM on Dec. 21, 2023
rainbow boa

In This Article

Species Overview

Brazilian Rainbow Boa Species Overview

The Brazilian rainbow boa is native to Costa Rica and central South America, where it can be found exploring grasslands and swamp environments. 

Brazilian rainbow boas’ scales are intricately patterned and have an iridescent quality, meaning that each scale refracts light like an optical prism to create a rainbow-like effect. Female rainbow boas tend to be slightly larger than their male counterparts. 

Rainbow boas are not venomous. However, these snakes can hiss loudly when feeling threatened to ward off predators. Rainbow boas have arrow-shaped heads that are significantly wider than their slender bodies. 

Although rainbow boas have poor eyesight, they can feel vibrations in their environment to sense what’s happening around them. Most rainbow boas are tolerant of gentle handling. But, like all other snakes, they may strike if they feel ill, stressed, or threatened.  

On occasion, snakes may mistake human hands as a food source. This sometimes happens during shedding periods, when the clear scales that cover the snake’s eyes (eye caps) become loose and impair their vision. Always approach a snake calmly and quietly and try to minimize handling when they are shedding. 

All reptiles are potential carriers of infectious diseases, including Salmonella bacteria, which is zoonotic (transmittable to people). Pet parents should always wash their hands before and after handling their snake or its habitat’s contents. 

Brazilian Rainbow Boa Characteristics 

Difficulty of Care 

Intermediate 

Average Lifespan 

Up to 30 years with proper care 

Average Adult Size 

4 to 6 feet 

Diet 

Carnivorous 

Minimum Habitat Size 

20 gallons long (20L) enclosure for juveniles; 75+ gallons for adults 

Brazilian Rainbow Boa Supply Checklist

To keep a rainbow boa happy and healthy, pet parents should have these basic supplies on hand: 

Brazilian Rainbow Boa Habitat

Choosing the Right Enclosure 

All habitats for a rainbow boa should be well-ventilated and secured with a screened lid to prevent the snake from escaping. A single, juvenile rainbow boa should be housed in a 20-gallon long (30” L x 12” W x 12” H) or larger enclosure. Once the snake reaches its adult size of 4 to 6 feet, it should be kept in an enclosure with at least a 75-gallon capacity.  

At a minimum, a rainbow boa's habitat should be long enough for the snake to stretch out their full body comfortably. For example, a 5-foot-long snake needs an enclosure with at least 5 feet of horizontal floor space. Always provide the largest habitat possible. 

Setting Up Your Habitat 

Rainbow boas are solitary animals that must be housed alone. Keeping more than one boa in the same habitat can encourage stress, aggression, and competition between tankmates. Pet parents should also never keep different species of animals in the same habitat. 

Temperature 

Like all other reptiles, Brazilian rainbow boas are exotherms, which means they rely on the heat in their surrounding environment to regulate their body temperature.  

Pet parents should use external heat sources to create a thermal gradient in their rainbow boa’s enclosure so the snake can warm up and cool down as needed. The recommended temperature for the warm end of a rainbow boa’s habitat is 85 F to 90 F, while the cooler end should be kept between 70 F to 75 F. Temperatures should not fall below 75 F at nighttime. 

Temperatures inside the habitat must be checked daily. At least two thermometers—one in the warm area and one in the cool area—should be placed in the enclosure so that both zones can be checked at once. A digital point-and-shoot thermometer can also be used to read habitat temperatures instantly. 

Light and Heat Sources 

Pet parents should install an under-tank heater and/or over-the-tank basking lamp with a heat bulb to supply radiant heat in their rainbow boa’s habitat. The wattage needed for the heat bulb will vary depending on the size of the enclosure, the distance of the bulb from the snake, and the ambient temperature of the room in which the enclosure is kept. Adjust the wattage of the bulb to maintain the recommended temperature gradient within the tank.

Note: Some light bulbs provide not only light to the tank but also heat and/or ultraviolet (UV) light. Pet parents should check the light sources they are considering to fully understand their function in the tank. 

Heat sources should be attached to a thermostat to keep temperatures within a safe and comfortable range. 

Hot rocks should not be used because they can get too warm and cause injury.  

If an under-tank heating pad is used, it must always be connected to a thermostat to prevent the snake from getting burned.  

Lightbulbs should never be placed inside a rainbow boa’s habitat and should instead be suspended above the enclosure with a light fixture. Otherwise, the snake may try to curl itself around the bulb, causing severe burns. 

White incandescent lights should not be left on continuously, as they will disrupt the snake’s natural sleep cycle and could harm its overall health. At night, turn off lights inside the snake’s enclosure or switch to a nocturnal or infrared light to ensure the snake can rest. 

UV Light 

Studies show that daily exposure to UVA/UVB light can improve reptiles’ immune system function and promote normal behavior. As a rule, pet parents should provide their rainbow boa with 8–12 hours of UV light daily to imitate natural sunlight. 

UV lights should be placed about 12–18" from where the reptile basks.

Replace lights every six months (even if they still emit light), because their potency wanes over time. 

Humidity 

Snakes need humidity in their environment to support their respiratory systems, encourage healthy shed cycles, and stay hydrated. The ideal humidity range for a rainbow boa is 70% to 80%. A hygrometer (humidity gauge) should be used to measure the enclosure’s humidity. 

To help maintain proper humidity levels, a rainbow boa’s habitat should include a water dish that’s large enough for the snake to soak in. A humid hide (a hideout box packed with moistened sphagnum moss or paper towels) should also be provided to boost humidity and encourage healthy shedding. Snakes that are not shedding in one piece may be actively soaked in shallow, warm water or misted with warm water from a plant mister. 

Bedding 

The bottom of a rainbow boa’s habitat should be lined with at least one to two inches of loose substrate. Paper-based bedding, cypress mulch, coconut husk, and aspen wood shavings are all suitable choices for substrate. 

When selecting a substrate for their rainbow boa’s tank, pet parents should keep a few things in mind: 

  • Pine and cedar bedding should not be used, as they have oils that can irritate a snake’s skin and cause illness. Since rainbow boas enjoy burrowing their snouts into their substrate, reptile carpet should also be avoided. 

  • If aspen is used as a substrate, it must be replaced weekly to prevent the bedding from getting excessively wet or soiled and becoming moldy.  

  • Wood shavings, mulch, and coconut husk bedding are all indigestible. If any of these substrates are used, the snake should be fed in a separate enclosure without any substrate. Otherwise, the snake may accidentally consume bedding that is indigestible and can cause gastrointestinal obstruction. 

Decor and Accessories 

Hideout Boxes

Rainbow boas are known to be shy, so their habitat should include multiple hiding spots for privacy and shelter. Pet parents should include at least two hideouts (one kept on the warmer side of the enclosure and one on the cooler side) in their boa’s habitat.  

Pet parents should monitor their rainbow boa’s behavior to be sure they are not hiding all the time, as they won’t have a chance to benefit from UV exposure. 

Synthetic or natural wood hiding logs are recommended. 

Hiding logs should always be large enough for the snake to fit inside comfortably, so pet parents need to increase the size of their hideout boxes as their snake grows. 

Pet parents can create their own hiding area by cutting a hole in a plastic container. If choosing to make a DIY hideout, make sure that the hole doesn’t have any rough edges that could injure a snake. 

Logs, Branches, and Climbing Shelves

Rainbow boas are semi-arboreal snakes, meaning that they sometimes enjoy climbing trees. Pet parents should furnish their rainbow boa’s habitat with branches or shelves to encourage exercise and help satisfy the snake’s natural desire to climb. 

Ensure any branches installed in the habitat are sturdy and strong enough to support the snake’s weight. Otherwise, the branch could topple over and potentially cause injury. 

For larger/heavier snakes, shelves can be a safer and sturdier option than branches. 

Food and Water Dishes

Since reptiles absorb water through their skin to stay hydrated, water dishes should be large and shallow enough for the snake to soak in if needed. 

Place water dishes on the cooler end of the habitat to prevent the water from evaporating too quickly. 

If the snake isn’t soaking on its own, pet parents should soak their snake for 10–15 minutes, two to three times a week. 

Moss

Moist sphagnum moss can be added to the inside of a hideout box on the warm side of a rainbow boa’s enclosure to create a humid hide. Moss holds moisture well and can aid in healthy shedding. 

Moss should be replaced often to prevent mold from forming. 

Brazilian Rainbow Boa Cleaning and Maintenance

A rainbow boa’s habitat needs to be cleaned and disinfected at least once a week with either a commercially available habitat cleaner or a 3% bleach solution. Pet parents should always wash their hands before and after handling their snake or its habitat’s contents, as all reptiles are potential carriers of infectious diseases. 

To clean a rainbow boa's habitat, take these steps: 

  1. Move the snake to a secure environment. Remove any old substrate, decor, and accessories from the habitat. 

  1. Scrub the empty tank and any furnishings with a reptile habitat cleaner or 3% bleach solution. The bleach solution should stay on the habitat for at least 10 minutes to ensure that the surfaces are properly disinfected. If using a commercial habitat cleaner, follow the manufacturer's instructions. 

  1. Rinse the habitat and accessories thoroughly with water, making sure to remove any trace amounts or residual smells left by the cleaning agent or bleach solution.  

  1. Allow the habitat and its contents to dry completely before placing new substrate and clean accessories into the habitat. 

  1. Return the snake to the clean habitat. 

Brazilian Rainbow Boa Diet and Nutrition

Brazilian rainbow boas feed on whole, thawed frozen rodents, such as mice and rats. Snakes should always have access to fresh, clean water. Use feeding tongs, not fingers, to offer meals. 

A nutritious and well-balanced diet for a rainbow boa consists of appropriately sized frozen rodents, thawed and warmed. Offer food in a shallow dish or bowl to lessen the chance of the snake ingesting its tank’s substrate by accident. 

A boa’s ideal feeding schedule will depend on its age, size, and activity level:  

  • Juvenile rainbow boas should be fed once a week. Pet parents should begin juvenile snakes on a diet of “pinkies,” or young and nearly hairless mice. As the snake grows into adulthood, it can be transitioned to a diet of slightly larger immature mice (“fuzzies” and larger “hoppers”). 

  • Adult rainbow boas should be fed once every one to two weeks. Adult rainbow boas can be offered full-grown mice and rats. 

  • Prey should be around the same size as the snake’s width at mid-body. For example, if the snake’s midsection is one inch in diameter, its prey should also be no wider than one inch.

Fresh, clean water should always be available and replaced daily. Water dishes should be placed on the cool end of the habitat and must be large and shallow enough for the snake to soak in if needed. 

Feeding Guidelines 

Live prey should not be fed. While still alive, rodents can become aggressive and leave severe wounds that lead to life-threatening infections. If the pet parent chooses to feed live rodents, they must supervise the snake closely and not leave them unattended. 
 
Ideally, feeding sessions should take place in a separate, empty enclosure that does not have any bedding material, so snakes cannot ingest bedding. Pet parents should always use long feeding tongs, not their fingers, to offer food to their snake. That way, the snake will not learn to associate their pet parent’s hand or the opening of their usual habitat with feeding. 

If you decide to offer food in your snake’s usual habitat, always offer it in a bowl not on the floor. Otherwise, the snake may accidentally ingest some of their bedding while eating. 

If a snake misses more than a couple of feeding sessions, the pet parent should consult a veterinarian, especially if the snake isn’t shedding at the time. Snakes can become ill if they don’t eat food for extended periods. 

How to Thaw Frozen Prey 

To thaw frozen prey, take these steps: 

  1. Remove the needed number of food items from the bag. 

  1. Put the frozen food in a sealed plastic bag and place it in a thawing container filled with cold water. The thawing container should only be used for thawing your reptile’s frozen meals. 

  1. Keep the food in the water until it thaws. Discard the cold water. 

  1. Refill the thawing container with warm water. 

  1. Place the thawed prey, still in the sealed plastic bag, in the warm water. Allow it to soak for 10-15 minutes before discarding the water. 

  1. Just before feeding, run nearly hot water over the thawed food to warm it above room temperature. 

  1. Remove the thawed food from the container and plastic bag.  

  1. Using feeding tongs, offer the food to the pet right away. 

Remember: Pet parents should never use a microwave to thaw or warm frozen rodents, and never offer food that's still frozen to a pet. Frozen food that is not consumed should never be refrozen for future use, as this encourages bacteria to form in the food.  

Avoid preparing frozen rodents in the same area that you use to prepare food for personal consumption. If this is unavoidable, be sure to disinfect the area thoroughly after use. 

Brazilian Rainbow Boa Grooming and Care

Shedding

Adult rainbow boas will shed their skin multiple times a year. Healthy snakes should shed their skin in one complete piece. Younger snakes that are actively growing tend to shed more frequently than adults. 

When snakes get ready to shed, their eye color turns cloudy blue or green, and their skin develops a whitish sheen. 

A snake’s eye caps, also called the spectacles, should come off with the rest of their shed skin. If the eye caps do not fall off, do not try to remove them; instead, consult a veterinarian. 

Snakes may become irritable and lose interest in eating while shedding. Avoid handling snakes during shedding periods.   

Snakes can soak themselves in a shallow, open water dish to help them shed and stay hydrated. Damp paper towels and moistened sphagnum moss should be placed in the snake’s enclosure to encourage healthy shedding. Pet parents can also mist their snake daily with warm water to support proper hydration. 

If your snake isn’t soaking on their own, pet parents should soak their snake for 10–15 minutes, two to three times a week.       

All reptiles are potential carriers of infectious diseases, so pet parents should always wash their hands before and after handling their snake or its habitat’s contents.  

If a snake misses more than a couple of feeding sessions or actively regurgitates food, the pet parent should consult a veterinarian, especially if the snake isn’t shedding at the time.

Brazilian Rainbow Boa Veterinary Care

Annual Care

Brazilian rainbow boas should be seen by a veterinarian once annually. They can be transported using a ventilated plastic lidded bin and snake bag. You can also take pictures of their enclosure, food, heaters, and lights (including exact specifications from the packaging) so your veterinarian can assess their husbandry as part of the exam.

Signs of a Healthy Brazilian Rainbow Boa

  • Clean, clear eyes

  • Intact skin with no ulcerations or stuck shed

  • Clean vent

  • No swellings or bumps

  • Regular flicking of their tongue

  • Relaxed demeanor

When to Call a Vet

  • Cloudy eyes or eyes that appear to have something stuck to the surface

  • Blisters, ulcerations, stuck shed, or other lesions on the skin

  • Discharge around the vent

  • Tumors

  • Lethargy

  • Loss of appetite

  • Redness or discharge from the mouth

  • Inappropriate body position that the snake can’t correct, especially on their back with the head lifted straight upward

Common Illnesses in Brazilian Rainbow Boas

  • Lack of appetite

  • Internal or external parasites

  • Skin infections

  • Respiratory disease

  • Oral infections

  • Dysecdysis (stuck shed, retained eye spectacles)

  • GI obstruction or constipation

  • Dystocia (stuck eggs)

  • Trauma including bite wounds if fed live prey

  • Prolapses

  • Inclusion body disease

  • Burns

Brazilian Rainbow Boa FAQs

How big do Brazilian rainbow boas get?

These snakes usually grow to four to six feet but can even grow as big as seven feet long!

Is a Brazilian rainbow boa a good pet?

Rainbow boas make great snake pets but aren’t a good choice for beginners, due to their size and some of their needs.

Can you hold a Brazilian rainbow boa?

While adult Brazilian rainbow boas are quite the handful to pick up, it is generally safe to do so. They’re slow-moving, gentle, and only young rainbow boas have a tendency to bite.

Are Brazilian rainbow boas endangered?

While not endangered, Brazilian rainbow boa populations suffer due to habitat destruction.

Can a Brazilian rainbow boa live in a 40-gallon tank?

Babies and juveniles can live in this tank size, but adult rainbow boas need larger enclosures.

Are rainbow boas aggressive?

Properly socialized rainbow boas are not aggressive, but those that are shy and unused to handling can react negatively to being picked up.

Featured Image: Murilo Gualda/iStock via Getty Images Plus


Maria Zayas, DVM

WRITTEN BY

Maria Zayas, DVM

Veterinarian

Dr. Zayas has practiced small animal and exotic medicine all over the United States and currently lives in Colorado with her 3 dogs, 1 cat,...


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