Viper Boa: Care, Appearance, Temperament & Breeding

Viper boas are found in their natural habitat in New Guinea. While they may look dangerous, they really aren’t and they make great pets.

These snakes have a bad reputation for being biters. However, if you probably socialize them, they don’t bite at all. This reputation comes from when they were caught in the wild and sold into the pet trade.

Viper boas can be quite high maintenance as their enclosures need to maintain a humidity level of 70% to 80%. This is what makes them intermediate snakes.

Common Name:Viper boa, New Guinea ground boa
Scientific Name:Candoia aspera
Natural Habitat:Swamps and wet marshland
Adult Size:2 to 3 feet
Lifespan:15 years
Diet:Small mammals, reptiles, amphibians, fish
Experience Level:Intermediate
Enclosure Size:3 feet long X 2 feet wide X 1.5 foot high for 1 Viper boa

Reptile Overview

Viper boas are great pets to have. They are nocturnal snakes who are ground-dwelling and love to dig. Having a bioactive enclosure is good for the animal, reduces maintenance, and is nicer to look at.

Viper boas have a slower metabolism than other snakes; therefore, their feeding maintenance is less. This makes up for the high maintenance required in keeping up with humidity levels.

Viper boas were targeted in the wild pet trade and this reduced their population numbers in New Guinea. We always recommend getting your Viper boa from a reputable breeder. Do not support the illegal pet trade.

Like most other boas, the Viper boa gives live birth. This means that their clutches are smaller and breeding large numbers of them takes a lot of time. However, breeding these boas is rather simple to do.


The Viper boa gets its name from the way it looks. It has a similar appearance to the Death Adder which is also native to New Guinea. The Viper boa is shorter than most boas and rather stocky and thick with a barely discernible tail.

The Viper boa reaches 2 to 3 feet in length.

Its head is the typical triangular shape of most of its family. However, it does have a slight scoop to it and this helps when the snake wants to burrow and dig itself into the substrate.

Viper boas have many different color morphs. They range from dark brown to orange, and can even be black. This is so the snake can camouflage in the leaf litter off the forest floor.

Viper boa near leafs on florest floor

Looks dangerous but pretty harmless!

This snake has a saddle-type pattern that runs the length of its body. However, the pattern does not extend to the snake’s belly. The belly is usually a lighter shade of yellow or tan.

These snakes are sexually dimorphic, the males have obvious spurs on either side of their vents even as juveniles.


Viper boas have a bad reputation for their temperaments. However, this is mostly for the boas that are wild-caught. When a snake is caught in the wild, it is subject to a huge amount of stress and carries parasites which gives it a “bad temper”.

Viper boas that are bred in captivity do not have these kinds of temperaments. If they are socialized appropriately from the time that they are juveniles, they hardly ever bite.


Viper boas are nocturnal snakes. This means that they are most active during the nighttime. Therefore, during the daylight hours, they tend to burrow under their substrate, hideaways, or leaf litter. They do this to get away from the sunlight.

These snakes are like other boas and constrict their prey. They are excellent hunters; however, they don’t need to hunt as often as other snakes as they have a slower metabolism.

These snakes enjoy a humid environment, they can often be seen soaking in their water bowls for large amounts of time. In the wild, they are known to go swim in the swamps!

Viper boa in white background

These snakes typically ball up in defense when threatened. If you see this behavior when you try to handle them, wait until the snake has calmed down. You can also spray your snake with some warm water to help it relax.


A Viper boa can live between 10 and 20 years. If you get your boa from a captive breeder it is more likely that your boa would enjoy a long life. However, if your boa is wild-caught then it may live a shorter life due to parasites and stress.


The Viper boa is not an arboreal snake. Therefore, the height of the enclosure is not as important as the amount of floor space your snake has. The enclosure should be a minimum of 3 feet in length 2 feet in width and at least 1.5 feet high.

Ensure that the enclosure is high enough for there to be a minimum of a 3-inch layer of the substrate. Your snake will need to burrow and hide in order to destress.

We suggest using a glass, plexiglass, or plastic enclosure. We do not suggest using a wooden enclosure as the high humidity levels were will encourage the wood to rot. The mold from rotting wood is bad for snakes and will cause respiratory problems.

REPTI ZOO Large Glass Reptile Terrarium

REPTI ZOO Large Glass Reptile Terrarium

A bioactive enclosure is the best enclosure for this snake as it reduces the amount of maintenance as far as humidity is concerned as well as creating an environment that is more natural for the snake to be in and more aesthetically pleasing for you to look at.

You’re your snake can also be kept and a rack system as it does not need much height. If you are keeping your Viper boa in a rack system ensure that the container is opaque and not transparent.

Your enclosure must have places for your snake to hide such as halved logs, coconuts that have been cut in half, upturned containers, or anything that is dark enough for your snake to hide in and feel secure.

Hideaways must not be too big or too small, they need to be big enough for your snake to fit in but small enough that your snake touches the sides of the hideaway.

Whichever enclosure you decide to use must be kept in a sanitary state. Snakes are very susceptible to bacterial and fungal infections. If the enclosure is not kept sanitary your snake will suffer from scale and mouth rot, respiratory infections, and parasite infestations.

You should do a full sanitization of the enclosure every 3 to 4 months. When you wash out the enclosure use a 1:1 water to white vinegar solution, you can also add a dash of bleach or you can use disinfectants made special for reptile cages like Zoo Med Wipe Out 1.

Zoo Med Wipe Out 1 Disinfectant

Zoo Med Wipe Out 1 Disinfectant

Ensure that you rinse the enclosure out completely with clean water before reintroducing your snake.



For a bioactive enclosure, we suggest using coconut husk or another kind of substrate that holds moisture well but will not become soggy such as cypress mulch, orchid bark, or aspen mulch.

Prococo Compressed Chips-N-Fiber Block

Prococo Compressed Chips-N-Fiber Block

Using a combination of coconut husk, sphagnum moss, and sand will provide a good anchor for any plants you use and will be loose enough substrate for your Viper boa to burrow into.

Galápagos Terrarium Sphagnum Moss

Galápagos Terrarium Sphagnum Moss

If you decide to go the bioactive route, we suggest adding isopods, springtails, and/or earthworms to your enclosure. These will help aerate the substrate and clean up any fecal messes you might miss. They will not harm your snake.

Isopods feed on fecal matter, springtails feed on mold, fungi, and dead material, and earthworms keep the substrate healthy.

You can add plants that will help to keep the enclosure humid and provide additional hideaway spots for your snake such as ferns.

Never use pine or cedarwood in the enclosure! They are toxic to snakes and can cause skin irritation and respiratory problems.


If you do not want to use a bioactive enclosure that is perfectly fine. Butcher’s paper, brown paper, or paper towels are all good options to use for a substrate. We suggest using some sheets of whatever paper you choose to line the bottom of the enclosure.

Cut or tear strips of the paper to create the 3 to a 5-inch depth that you will need for the substrate. These strips of paper will allow your Viper boa to burrow and feel secure.

When you have placed the paper substrate in the enclosure spray it down so that it is damp but not sopping wet.


Spot clean the enclosure once a day.

If you are using a bioactive enclosure you will need to add to the substrate every 2 to 3 months. If you are using paper as a substrate you will need to replace all of it watch every 2 weeks.


Maintaining a temperature gradient is key to the health of your snake. The temperature gradient is there so your snake can choose whether to be warmer or cooler depending on its current state of metabolism.

We suggest using an under-tank heating pad placed under one-half of the enclosure. This heating pad should be connected to a quality thermostat.

VIVOSUN Reptile Heating Pad with Digital Thermostat

VIVOSUN Reptile Heating Pad with Digital Thermostat

There should be hideaways on the cool side of the enclosure, in the middle, and at the warmest point. There should be sufficient cover or depth of substrate between these hideaways so that your snake can move freely without feeling exposed.

The substrate on top of the heating pad may need to be shallower than elsewhere to ensure that the appropriate amount of heat is getting into the enclosure.

Cool Side: 75°F

Warm Side: 85°F

Basking Area: The Viper boa does not bask in the wild. Therefore, it does not need a heat lamp or a ceramic heating emitter. These will dry out the enclosure.

You must place a thermometer on the cool side and the warm side of the enclosure to keep track of the temperature gradient.

Zoo Med Labs Digital Hygrometer and Thermometer

Zoo Med Labs Digital Hygrometer and Thermometer


The Viper boa is a nocturnal snake; therefore, it does not need special lighting.

However, it should still be exposed to a 12/12 light/dark photocycle. This can be done by installing a low wattage bulb inside the enclosure or by placing your snake’s enclosure in a room that receives daylight.

Zoo Med Reptisun Led Terrarium Hood

Zoo Med Reptisun Led Terrarium Hood

If you use a light bulb it must be attached to a timer to ensure that the photocycle is not interrupted as this will cause your snake to stress. For this purpose we are recommending to use Zilla Digital Timer.

If you are using a regular lamp which heats up, make sure the bulb is in a protective dome to avoid injuries to your snake.

If you place it in a room that receives daylight, make sure that the sun does not fall directly onto the enclosure as the increase in temperature will be fatal for your snake.


The humidity requirements are what makes the Viper boa an intermediate-level snake.

Your snake requires a 70% to 80% humidity level. There are a number of ways you can achieve and maintain this level of humidity.

You can use a bioactive enclosure with natural plants as this will help maintain humidity levels. However, you will need to maintain the plant life as well as your snake’s enclosure.

Another way you can maintain the humidity levels in your snake’s enclosure is to install misters. The misters will be on timers that will periodically mist the enclosure to maintain the humidity levels.

REPTI ZOO Reptile Mister

REPTI ZOO Reptile Mister

You could also manually mist the enclosure daily when you’re doing a spot clean.

Your substrate should never be wet enough that water can be squeezed out of it. If this happens it means that the enclosure is too humid for your snake.

You must install a quality hygrometer to keep track of the humidity levels, we advise checking the levels at least once every 2 days.



Viper boas love water. Their enclosure must have a water bowl that is large enough for them to fit in to soak.

The water bowl must not be porous or light enough that it can be tipped over as this will increase the humidity to a dangerous level.

The water must be changed daily or as soon as you see the snake has messed in the water.

We suggest placing the water bowl half over the heating pad. This will help maintain humidity levels and keep the water warm enough for your Viper boa to soak in.


Viper boas have slow metabolisms, which means they eat less often than other boas. Juveniles should be fed once a week and adults once every 14 to 21 days depending on the individual.

They should be fed one prey item of appropriate size. Use our sizing guide to help you:

Largest point of girth of prey = Largest point of girth of snake that is not its head

Rodents are appropriate prey items. You can use chicks and feeder fish as treats for dietary variation. The feeder fish can be placed in their water bowl and the Viper boa can then ‘hunt’ the fish. This provides enrichment and the fish cannot harm the snake.

We suggest Frozen/Thawed (F/T) prey items only. We never suggest live or stunned prey.

Live prey can injure your snake, carry parasites that would be killed off in the freeing process for F/T prey, and cost you extra money and time to properly maintain.

When it comes time to feed your snake, place the F/T prey item in a bowl of hot water and wait for it to come to room temperature. Once it is completely thawed, use tongs to feed your boa.

unlumm Feeding Tongs 15" 2 Pcs

unlumm Feeding Tongs 15″ 2 Pcs

If the prey item is not completely thawed out, the temperature difference will kill your snake.

We suggest feeding your Viper boa in its enclosure. This will not encourage it to be more aggressive and bite.


Always sanitize your hands and wear clean clothing before handling your snake and especially between handling different reptiles. Snakes are very susceptible to parasite infestations and bacterial infections.

Make sure that you do not handle their prey items before handling your snake as your hands will smell like food and prompt your snake to bite.

You can hook train your snake if you do not feel comfortable picking up your Viper boa with your bare hands. It is a good idea to use a hook if your snake is buried in the substrate.

DocSeward Snake Hook

DocSeward Snake Hook

To do this you should gently stroke your snake with the hook and make it away from the hook. Then hook the heaviest point of the snake and slowly lift it out of the enclosure and support the rest of its body weight with your other hand.

Make sure your movements are slow and steady. If you are scared of handling and worried about getting bitten then wear a bite-proof glove. This will calm you and because you are calm, it will calm your snake.

Never handle your snake 24 hours before, during, or for 48 hours after feeding. The stress this causes the snake will make it regurgitate its food.

We recommend handling your Viper boa one to two times a week for a maximum of 1 hour.

Potential Health Issues

Respiratory Problems

Humidity levels that are too high or too low will interfere with your snake’s lungs and can lead to a respiratory infection. You will notice your snake is gurgling or blowing bubbles. Get it to an exotic vet as soon as possible.


The Viper boa is a chubby-looking snake and so some people tend to overfeed them. This leads to obesity. A fat snake is not a funny snake. Obesity puts a strain on the heart and kidneys which can prove fatal.

Stick to a strict feeding regime and do not try to power feed your boa.


Mite infestations are fairly common with snakes kept in unhygienic enclosures. They appear as small black or red dots on the substrate or your snake’s skin. They usually cluster around the eyes, nose, and mouth.

They burrow under the scales to get at the blood. They carry their own parasites so getting rid of them is a top priority. Your snake will need to be soaked and the enclosure will need full sanitization.

Scale and Mouth Rot

Due to the humid nature of their enclosures, mold which causes bacterial infections of thin membranes can easily become a problem.

This can be avoided by keeping the enclosure clean, daily spot cleaning, daily refreshing of water, and ensuring their prey items do not carry any parasites or spores on them.


Provided there is enough space, multiple Viper boas can be kept in the same enclosure. Add 10 gallons to the enclosure per boa and add a large enough water bowl for at least 2 boas to fit in at the same time.

A slight cooling period called brumation is necessary to optimize breeding conditions.

In October, slowly lower the temperature by 10°F. Reduce the photocycle to 14/10 light/dark. During this time feed them only once a month. In January, slowly increase the temperature and reset the photocycle back to normal.

There are known cases where no brumation period was provided and the Viper boas still reproduced so keep that in mind when you keep males and females together.

Viper boa head macro

At the end of January, start feeding them every 14 to 21 days again. The females may refuse prey at this time. The males and females will start mating when the temperature returns to normal.

They are known to mate in their water bowl so look out for this interesting behavior!

The females will be gravid between 7 and 9 months. The female keeps the eggs within her body and then “gives birth” to live babies. The clutch can be between 10 and 20 individuals.

Remove the babies from the main enclosure as the small neonates can be cannibalized by the adults. You can keep them in shoebox-sized containers until they start growing. Feed them a small pinkie at around 3 weeks or after their first shed.


Viper boas or New Guinea ground boas (Candoia aspera) make wonderful pets. They are now in the captive-bred market and should never be caught in the wild for the illegal pet trade.

They are chunky boas have great temperaments when they are handled regularly and with care. They are stunning to look at and have really cool behaviors that you can watch.

We “herp” you and your boa friend have a wonderful journey together!