Rainbow Boa Care Sheet

My first proper introduction to rainbow boas was as a teenager, when I started to date a girl who kept one as a pet.

I was immediately taken with the incredible iridescence shown under natural sunlight (or the right artificial lighting).

It is this ever-changing color that has resulted in their common name of “rainbow boa”. Overlaid on a red or orange background there is no denying that rainbow boas are absolutely beautiful animals.

Since that first encounter rainbow boas have always been a firm favorite of mine. Not only are they stunning snakes to have in the home, but they also grow to a respectable size, can be far more active than many other popular snakes and can become incredibly tame with gentle, ongoing handling.

If there is a downside to keeping rainbow boa as pets it is that they are slightly more fussy with the conditions they require.

Once these care conditions have been achieved, rainbow boas can live long and healthy lives, with many specimens allegedly living to 20 years or more.

In this rainbow boa care sheet we’ll look at what makes Brazilian rainbow boa care different to other snakes, and the best ways to achieve these unusual conditions in the home.

Natural Habitat

Brazilian rainbow boas have the Latin name Epicrates cenchria. Rather than one single species there are actually a number of different recognised rainbow boas. Fortunately the care of all species tends to be very similar indeed.

The most popular of all is the Brazilian Rainbow Boa. While this species is found in Brazil, it can also be found widely distributed across much of Central and South America, including Costa Rica, Perú & Venezuela.  

Growing to between 5 and 7 feet on average in total length – with females typically getting slightly longer while males are more muscular – these are typically nocturnal snakes. Rainbow boas are equally at happy on the ground and are known to be far more active than many other pet snakes.

As might be expected from an animal found in and around the rainforests of Central and northern South America they appreciate a high level of humidity – a crucial topic that we’ll cover later on in this care sheet.

Caging & Enclosures

The key to successfully keeping rainbow boas in captivity is getting their environmental conditions right. These requirements are quite special, so considerable thought is required to select the most suitable vivarium.

A suitable rainbow boa cage should incorporate the following elements:

Size

As a general rule of thumb your snake should be able to fully stretch out in it’s cage. For hatchlings this means that a small 10 gallon tank or plastic showbox can work well. However adults will require far more space. An enclosure of 48” / 4 feet / 120cm in length is advised, with a depth of around 24” / 2 feet / 60cm.

Dimensions

Brazilian rainbow boas are quite active snakes, and will sometimes climb when given the opportunity. While the floor space has already been discussed, permitting some vertical height with branches to climb on is also recommended.

For this reason many people do away with very low tanks, and instead aim to offer 24” / 2 feet/ 60cm or more of vertical height. This seems to particularly benefit larger, more mature snakes.

Humidity

As we will discuss later, a crucial part of successful Brazilian rainbow boa care involves the provision of high levels of humidity. This means that cages offering too much ventilation are often not ideal. For example, if you opt to use a glass fish tank with a standard reptile-safe mesh lid then you’ll want to block off part of the mesh to retain humidity.

This is one reason why “enclosed” vivariums such as those made of plastic can be particularly successful. If you opt to purchase or buy a melamine wooden reptile vivarium then be sure to add silicone sealant to the joins of your rainbow boa tank. This prevents moisture from entering the timber, shortening the lifespan of your cage.

Air Flow

While we want to maintain a humid environment, some air flow is still important to prevent a build-up of mould. Cages which give you the opportunity to vary their ventilation can work particularly well for Brazilian rainbow boas.

Heating

If you live in a temperate part of the world then it’s likely you’re going to need to provide some supplementary heating – at least in the winter months. Think about how you’ll achieve this in the confines of any vivarium you’re considering. More information on temperature and heaters is provided later in this care guide.

Best Cages / Vivariums for Brazilian Rainbow Boas

Now we’ve got the essentials out of the way let’s take a closer look at some specific vivariums that should be suitable for your rainbow boa.

Plastic Shoe Boxes

Many small plastic containers can be turned into a suitable cage for baby rainbow boas. Personally I use Really Useful Boxes in the UK, as I like the way that the lid clips on for additional security.

The one thing you’ll need to do is to add some ventilation holes for your rainbow boa. Either cut out a section and replace it with fine gauze/mesh, or use an electric drill (my preference) to just drill a number of holes.

You may need to experiment with ventilation over time, keeping an eye on the humidity within the container. Small hygrometers are cheap to buy and easy to install, and allow you to monitor humidity easily.  

Glass Terrariums

I utilize glass vivariums extensively in my exotic pet collection. They look great, they’re easy to heat and add lighting to and the front-opening doors make routine maintenance quick and simple. They can also be of use to rainbow boa keepers – with a few provisos.

Firstly, most glass terrariums come with a mesh lid, which means that retaining humidity can be challenging. Therefore if you’re going to use one, be sure to block off some of this mesh. The easiest option I have found is simply to purchase some thin perspex which I place over the top.

A second weakness is that glass terrariums only come in a limited range of different sizes. This means that while they can work quite well for juvenile rainbow boas they may not be the best option for a full-sized adult rainbow boa.

For someone with a hatchling who wants a mesmerizing display, however, they can work well.

Aquariums With Mesh Lid

Aquariums come in a far wider range of different sizes, and even 48 inch / 4 foot long aquariums are quite cheap to buy. Historically the issue has always been how to prevent your snake from escaping; after all snakes can get through the tiniest of gaps. This has been solved thanks to the use of mesh lids which fit over the top.

As with glass terrariums, while this mesh prevents escapees, it allows for too much humidity to evaporate. Once again, therefore, you’ll want to block some of this off to maintain the right humidity levels in your cage.

You’ll also need to consider that such cages have to be accessed from the top, which can be slightly less practical.

All told, however, with a few minor changes a glass fish tank with a (modified) lid can represent a cost-effective snake enclosure.

Wooden Vivariums

I love wooden vivariums and use them for many of my snakes. They’re cheap to buy (or cheap to build) and the wood helps to retain moisture and heat making for a comfy home. They also come in a wide range of sizes so can be ideal for even large adults.  

If you’re planning to buy or build a wooden vivarium for your snake then there are a few considerations to bare in mind. Firstly, be sure to use aquarium-safe silicone sealant to seal all the joints where the panels meet. This will prevent moisture getting into the wood and causing damage.

Secondly, be sure to select (or make) a vivarium that includes air vents, permitting a degree of air flow.

While wooden vivariums therefore represent a decent option for those on a budget, the humidity required by your rainbow boa mean that such enclosures may not last as well as other options.

Plastic Cages

A small number of plastic vivariums are available on the market – such as those made by Vision. While far from cheap, these are arguably the most practical option of all.

Made from a single piece of molded plastic they won’t rot in humid environments, are easy to keep clean and hygienic and have been tested by serious reptile keepers for years.

If you’ve got a decent budget – and a large rainbow boa – then these are probably the best vivariums on the market right now.

Heating & Temperature

Perhaps rather unusually for pet reptiles, rainbow boas don’t tend to do very well in overly-hot enclosures. While a temperature that is too cool may result in your snake becoming less active or going off it’s food, particularly high temperatures can lead to death. This is a somewhat unique aspect of rainbow boa care, where many similar species love a tasty hot environment.

You’ll therefore need to maintain your Brazilian rainbow boa’s cage within a very limited range of temperatures.

The best temperature for a rainbow boa is between 75 degrees F and 80 degrees F (23-27 degrees C) during the day. This can drop a few degrees at night without worry.

It is generally best to heat one end of the tank, allowing the other end to remain cooler. This creates a temperature gradient, permitting your boa to seek out the area that suits it best.

There are a range of pieces of reptile heating equipment that can help you to accomplish these temperatures:

Heat Mats & Pads

Possibly the cheapest and easiest solution is a low-powered heat mat. A suitably-sized mat can be purchased to heat just ¼ to ⅓ of the snake tank. This should be placed on the bottom of the cage.

The issue with heat mats when it comes to rainbow boas is how best to install them. The heat may struggle to pass through wood or thicker plastic, meaning that it has to be placed directly inside the cage.

While heat mats are waterproof to a degree, they can struggle in a humid environment. As a result, if you opt to use a heat mat either place it under the enclosure (if you’re using a glass vivarium) or inside it, but under the substrate, in other cages. Be sure to monitor it regularly to make sure the heater doesn’t suffer from moisture ingress.

Please note that due to the reasonably modest upper temperature level it is crucial to use a thermostat with the heat mat. The probe should be placed at the hottest part of the cage to prevent overheating. Click here to learn more about choosing the right reptile thermostat.

Ceramic Bulbs

Ceramic bulbs represent a great alternative for your rainbow boa, and are one of my favorite type of heaters of all. These bulbs are placed inside the cage, and reflect heat down to a basking spot below. They don’t produce any visible light so can be left on 24/7 and can be handy for heating larger adult snake cages.

No products found.

It is important to note that ceramic bulbs can get very hot and produce high temperatures within your snake cage. There are two important considerations before installing a ceramic bulb. Firstly ensure you install a suitable bulb guard, which will prevent direct contact between your snake and the bulb. Doing so eliminates the chances of burns.

Secondly, as with other reptile heaters, be sure to choose a suitable thermostat. Note that you’ll need a very different type of thermostat for a ceramic bulb. If you’re unsure read my thermostat guide here.

I also have a beginner’s guide to using ceramic reptile heaters here.

Heat Lamps

Not my preference, but some keepers opt to use a heat lamp that produces visible light. All the standard rules – bulb guards and thermostats – also apply here.  

Lighting

Brazilian rainbow boas, like their cousins, are typically nocturnal snakes. Therefore artificial lighting isn’t crucial for effective rainbow boa husbandry. That said, without such lighting you’re unlikely to see your rainbow in their full glory.

As a result, while it is by no means a necessity, many keepers opt to install artificial lighting. If you opt to go down this route aim for a bulb that mimics the wavelengths given off naturally by the sun, so you can enjoy the full iridescence of your snake.

As rainbow boas are nocturnal be sure to only leave the lights on during the day, allowing for suitable darkness at night.

Water & Humidity

As we have discussed, your rainbow boa should be maintained at a high relative humidity if it is to thrive in captivity.

Stories abound on discussion forums about specimens passing away when they have been kept too dry.

Water and humidity is therefore one of the most important elements of all to successfully keeping rainbow boas as pets. Here’s what you need to know…

Water Bowl

Your rainbow boa should have access to a bowl of fresh water at all times. This water bowl should be thoroughly cleaned daily in reptile-safe detergent to prevent the build-up of potentially harmful bacteria.

Like many other snakes, Brazilian rainbow boas will often attempt to fully submerge themselves in their water bowl for a good soak. This dictates the size of the water bowl; it should be large enough that your snake can entirely curl up inside it, with a water level that is low enough that it won’t spill out while your snake bathes. A wide, shallow water bowl therefore tends to work well.

As Brazilian rainbow boas are surprisingly strong snakes my personal preference is for a heavy stoneware cat or dog water bowl (depending on the size of the snake) that isn’t easily up-ended or moved around the cage.

Regular Misting

Rainbow boas thrive when the humidity in their cage sits at around 75-90%. In order to accomplish this invest in a good-quality houseplant spray gun and routinely mist the inside of the vivarium.

It may be necessary to do this daily to maintain the correct moisture levels. Be sure to use lukewarm water and try to avoid misting directly at your snake.

Controllable Ventilation

Just because your rainbow boa appreciates a humid environment doesn’t mean that there should be no ventilation. A warm, stuffy cage creates the perfect environment for microbes and mould to grow.

Therefore you should select a cage that allows for air movement.

Best of all are cages with variable ventilation, so you can experiment with mistinging and ventilation to create the optimal environment.

Hides

To help maintain high humidity levels many keepers opt to provide a “moss box” for their snake.

A snake-safe hide is added to the cage, under which moist sphagnum moss is placed. This moss itself can be moistened every few days. In this way your snake will always have somewhere humid to sit if it so desires.

Suitable Substrate & Regular Cleaning

It is important to appreciate that a high humidity can not only rot substrate but can allow mould to grow. Neither of these is acceptable for a pet rainbow boa.

Therefore be sure to choose a substrate that works well in a humid tank, and take care to remove uneaten food, faeces and sloughed skins promptly to keep the cage hygienic.

Best Substrates for Rainbow Boas

The most important thing when considering which substrate to choose for your rainbow boa tank is whether it can withstand a humid environment. Many popular snake substrates quickly rot and go mouldy under such conditions.

Fortunately there are still a range of options available to you. Some of the best substrates are:

• Cypress mulch
• Orchid bark
• Rainforest substrate
• Coir granules (coconut fibre)
• Chemical-free potting compost
• Paper towels (if these are replaced regularly)
• Newspaper (I dislike the use of newspaper but many use it successfully)

Even when using these substrates be sure to keep a close eye on any mould that may appear and spot clean it as necessary.

Brazilian rainbow boas don’t tend to dig too much, so a deep substrate is unnecessary. Personally I like to use just a couple of inches of substrate. I like to routinely mist the substrate as well as the rest of the tank, so that it retains and slowly gives out moisture.

Vivarium Decor

We’ve discussed the importance of a decent-sized water bowl and a substrate that can cope with high humidity. You know how to heat and light your cage now too. But what else should be present in terms of enclosure decor?

Here are some suggestions to consider:

Hides

All snakes kept as pets should have the opportunity to hide away from view when it suits them. Brazilian rainbow boas are really no different.

Whether you use a moulded “cave” for your snake, a piece of hollow cork bark or even just a cereal box your snake should be able fully conceal themselves in the hide.

If the cage allows I like to include two different hides – one at the warm end and one at the cooler end.

As discussed earlier, consider stuffing one of these hides with damp sphagnum moss to further increase the humidity available to your snake.

Climbing Branches

Rainbow boas will catch birds in the wild if the opportunity presents itself. While not fully arboreal many keepers find that their snake happily climbs around any branches present.

To add environmental enrichment for your snake – as well as making your vivarium look impressive – consider adding some sandblasted vines or other branches for climbing.

Artificial Plants

Artificial plants aren’t an absolute necessity but they can add visual interest to your boa cage, as well as giving your snake more privacy. I’m a fan of using artificial silk plants which can look very realistic indeed in snake enclosures. They’re also simple to clean.

Rocks and/or Wood

Lastly, rocks or other pieces of wood can be added to the cage. These are often used by snakes to help rub off their old skin when moulting. I strongly encourage you to buy these from a reputable reptile store to reduce the odds of introducing parasites into your rainbow boa cage.

Also, be sure these are securely fitted so they can’t crush your snake. Wood, for example, can be siliconed or tied into place to prevent it moving or falling.

Food & Feeding

As with choosing the right enclosure, proper diet is another crucial key to successful Brazilian rainbow boa care. Fortunately, being so widespread in their native habitat, Brazilian rainbow boas have been studied extensively in both the wild and in laboratories.

One fascinating piece of work involved dissecting preserved museum specimens to examine the contents of their stomachs. The scientists noted that “mammals constitute the primary prey” while less often rainbow boas may “prey on birds more opportunistically”.

This very closely matches up to what reptile keepers have long grown to know – that suitably-sized rodents make a perfect staple diet for rainbow boas. Larger specimens may also accept the odd day-old chick to vary their diet.

Brazilian rainbow boas tend to have a healthy appetite in captivity, being far less fussy likely to go on extended fasts than ball pythons. Most will readily accept pre-killed mice and rats of a suitable size. These are most easily bought frozen. 

Live feeding of rodents is never recommended if it can be avoided, as this not only places your snake in danger of bites or scratches, but is illegal in some countries too (I’m looking at you UK!).

Rainbow boas will usually accept a rodent of the same size as the widest part of their body. Smaller prey can still be fed if that is all that is available to you.

I personally maintain a freezer filled with different sized mice and rats for my collection.

On feeding day a suitable frozen rodent is removed from the freezer, placed into a plastic bag and suspended in warm water. This helps to speed up the thawing process, and also ensures you’re feeding a “warm” rodent to your rainbow boa. I have found that this seems to make the rodent more appealing to many snakes. Ensure the rodent is “pliable” and fully defrosted before feeding. 

Be careful when feeding as some snakes may strike in your direction, unaware you are not the rodent. It is generally easiest and safest to use feeding tongs or long forceps to place the rodent into the tank.

Bearing in mind that rainbow boas are naturally nocturnal it generally makes sense to with feeding time. Consider feeding your boa late in the evening as the light is starting to dim. 

Some keepers like to feed their snake using tongs, removing the prey if the snake doesn’t strike. Personally, I find that some rainbow boas are shy when eating, so when I feed snakes I like to leave the food item in the enclosure for some hours to give the snake a chance to eat in peace. If you find that the prey remains uneaten the next morning then remove it to avoid spoiling.

Also be sure to spot clean any substrate as necessary; in the humid environment of a Brazilian rainbow boa cage any debris can quickly become unpleasant.

In terms of feeding frequency, most baby rainbow boas will eat every 4-5 days, while adults are typically fed every 7-10 days. A “once a week” schedule for both babies and adults is a good rule of thumb, modifying this routine in response to your boa’s appetite. 

The larger snakes get, the more relaxed you can be about feeding schedules. Adults may be alright for slightly longer periods of time if, for example, you’re heading off on vacation. 

Be aware that, like some other popular pet snakes, rainbow boas can become obese in captivity. Moderate feeding and suitable space to move around should help to limit this risk.

Lastly note that like other snakes, Brazilian rainbow boas may go off their food for some weeks before they slough their skin. So long as the environmental parameters are correct, your pet has water, and they don’t seem to be losing too much weight then this really shouldn’t be anything to worry about. 

Handling

One reason why Brazilian rainbow boas have become so popular over the years is their calm demeanor as adults.

They attain a size that is easily managed in captivity; large enough to enjoy handling without risk of damaging your pet, but not so large as to worry about dangers to your own health if things go south.

This not only makes them pleasant to handle but of course means that carrying out health checks becomes that much simpler. 

Hatchlings, in contrast, are often rather more feisty and may attempt to strike while they are being got out of the cage.

The key is starting early and putting in the necessary time to familiarise your snake with handling. Get your snake used to short, calm periods of handling. It is often safest to use a snake hook to gently remove your rainbow boa from their enclosure. Once outside most specimens calm down considerably.

Scientific studies have shown that the females – which tend to grow slightly longer – tend to adapt more quickly to handling.

Handling rainbow boas can be particularly rewarding as these are such active snakes.

Unlike a ball python that may just sit motionless in your hand, rainbow boas tend to represent a much more engaging experience. On the other hand, due to the heightened activity level be sure to hold the snake securely, ensuring that the cage remains open so it can be easily replaced.

Ideally aim to handle your snake over a low, soft object such as a mattress, so that if it should make a break for freedom then it won’t suffer damage in the fall.

Any suggestions or questions after reading our Brazilian rainbow boa care sheet? Please leave your opinions and ideas in the comments section below…

Photo by berniedup