Edited by Dr. Robert G. Sprackland
The Pacific Island Boas (Candoia ssp.) are both my nemeses and my love. I enjoy everything about these boas and once had an opportunity to obtain some at incredible price. Sadly, being a broke writer I was unable to get them. Since then, they have come and gone as I have watched and listened to stories of keepers’ successes. I’ve yet to keep these myself as pets, but I was able to work with them at a couple of the shops where I worked.
Natural History of Candoia spp.
Johann Gottlo Schneider originally described Boa carinata in 1801, and in 1842 thanks to John Edward Gray become Candoia carinata. Four more snakes were later added to the same genus. Candoia bibroni bibroni was described as Enygrus bibroni by Dumeril _ Bibron in 1844. There’s also another subspecies of Candoia bibroni known as C. b. australis.
In 1863 Albert Guenther described another Pacific boa as Enygrus superciliosus, presumably referring to the snake’s enlarged supraocular scales. In 2001 Hobart Smith and David Chiszar renamed the species as Candoia superciliosa which is now known by the common name Belau Bevelnosed Boa. Smith and Chiszar went on to describe a subspecies as well C. s. crombiei which is known as the Ngeaur Bevelnosed Boa.
In 1877 Guenther again described a boa species as Erebophis aspera which Forcart elevated to full species in 1951. Forcart also described the subspecies C. a. schmidti. These are commonly known in the trade as New Guinea Ground Boas or New Guinea Viper Boas.
In 2001 our friends Smith and Chiszar made additional taxonomic changes. They took Olive Stull’s Enygrus carinatas paulsoni and elevated it to Candoia paulsoni and then added on 5 subspecies (C. p. paulsoni, C. p. vindumi, C. p. mcdowelli, C. p. sadlieri, and C. p. rosadoi). This species is commonly known as Solomon Island Ground Boa. The genus Candoia ranges over a large portion of the Pacific Islands and Papua New Guinea.
This time in English
Currently recognized Candoia species and subspecies are:
New Guinea Ground Boa: Candoia aspera aspera, C. a. schmidti
Pacific Boa: Candoia bibroni bibroni and Fiji Island Boa: C. b. australis
Pacific Boa: Candoia carinata carinata and New Guinea Tree Boa: C. c. tepedeleni
Solomon Island Ground Boa: Candoia paulsoni paulsoni, C. p. vindumi, C. p. mcdowelli, C. p. sadlieri, and C. p. rosadoi
Belau Bevelnosed Boa: Candoia superciliosa superciliosa and Ngeaur Bevelnosed Boa: C. s. crombiei
Zig-Zags _ More
To say that Candoia are odd ducks when it comes to the boid family is an understatement. The visible characteristics of these boas would likely tell us, and it’s accepted in most circles, that this genus is using Batesian mimicry of the venomous Death Adders (Acanthophis ssp.) with which it is sympatric (living in habitat which overlaps). Viper Boa is another common name for Candoia aspera. Most Candoia are some shade of brown and/or black. Of note is the dorsal (back) pattern, which I can only equate to a zigzag pattern like a Ziggurat. In Candoia carinata paulsoni the ground (meaning the overall or base) color of the snake is cream to white and the zigzags are a dark chocolate brown which makes for an incredibly stunning snake. There are also some red species which I have seen where the ground color is a deep red and the pattern is a dark brownish color. As can be seen above.
Generally males are smaller than females. Cloacal spurs on males are larger than in females and is a good way to sex these snakes. Pacific Island Boas, depending on subspecies, range in size from two feet up to just under six feet.
Captive Care of Candoia at Reptile Apartment Group
The entire genus Candoia is one that would be considered tropical species. When keeping tropical species three things should come to mind: Heat, humidity and UVB. Some may have said humidity and heat. In addition to heat, most tropical reptiles in our experience also require humidity and UVB. With snakes it’s a long standing presumption that snakes don’t benefit from UVB. However, we’ve not seen reports of blood calcium levels which would prove UVB is not necessary.
A custom built enclosure is probably going to be the best bet. You also have the option of the Exo Terra High Glass Terrarium, 36 by 18 by 36-Inch. I’m a fan of tropical reptiles, amphibians, and invertebrates but the substrates always seemed too moist and would grow fungi. Then I learned of air circulation (one of those DOH! moments). Stagnant air (air that’s not moving) helps bacteria and mold grow. Exo Terra sorted this out with their revolutionary design of air vents on the front of the enclosure with a screen lid therefore directing the air from the bottom and bringing it up and out of the vivarium. For a custom enclosure, there are numerous plans available I’m sure. The one we found which we liked the best is Candoia.ca unfortunately the site is as of this writing not available. We’ve not constructed one from this plan yet but from our experiences and those of other keepers this plan is the best we have found.
Consensus has it (various authorities in herpetoculture) that there should be a basking area of 30-32C, with an ambient of 26-28C. Heat can be provided in numerous ways, from ceramic heating elements to under tank heaters and colored bulbs. We are going to explore the best options as well as share why the other types are not good options.
If you’re a regular reader skip the next two sentences. You shouldn’t use colored lights as they will disrupt the normal circadian rhythms of the reptile. We have explained this in the article “Colored Lights and other Myths the Pet Store told me.” Ceramic heating elements are the best way to go. Sometimes the enclosure you’re using needs an alternative way of heating. Therefore, we have what are known as under tank heaters which make for excellent secondary heating source with the Candoia spp.
If you’re using a heater of ANY KIND you MUST use either a thermostat or a rheostat. To get more in depth with heating and getting the right temperatures see our full length report Heating: The Goldilocks Principle of Herpetoculture. Armed with the information in that report you should be able to tackle any heating issue.
At first glance, that may seem an odd combination substrate and humidity. The two are interwoven and will play a major role in keeping a healthy Candoia in captivity. Substrates are like the heating sources, where there are numerous opinions and they all claim to be right. To cut to the chase of the substrate, we recommend and use EarthGro Organic Orchid Bark and EarthGro Organic Soil for all of our tropical species of reptiles, amphibians, and invertebrates. For the boas we will often tear up and place a few mats of sphagnum moss to hold more moisture. If you’d like to read a more in depth treatise on substrates then we recommend the Substrates: Getting Your Hands Dirty article.
Before you ask about impaction here is another tip.
We always remove our snakes from their enclosures when feeding. We place them into a bucket and or plastic tub then place the thawed rodent (see State of Prey) in the same and allow them to eat. Once finished we move them, gently, back to their normal enclosure. For the next forty-eight hours they are left alone to digest their meal.
Back to the substrate thing. Does the substrate hold water or just go right through it? If the substrate is able to hold water and dry over time via evaporation then this substrate is a good choice for tropical species of reptiles which need humidity. That’s the link between substrate and humidity.
Why decor is not covered more often within herpetoculture is beyond us here at Reptile Apartment Group, but that’s another topic. For now suffice it to say, in our experience an enriched environment with various types of decor appears to have a direct correlation with a healthy snake. Not just physically, but also their behaviours seem to be calmer and not as flinching when a naturalistic environment is provided. Live plants should be offered for Candoia not only low growing plants for cover but also some taller species.
We want to provide a couple of wide branches or, even better, cork tubes which can support the heavy bodied snake. On these branches/tubes we can trail around some Pothos or maybe some Creeping Charlie. Here is something I was not aware of but the statement makes total sense when we look at the snake in it’s natural habitat and observe its behaviors in the wild. The author at Candoia.ca has some great naturalistic observations and we highly recommend that site. The observation which stuck out for me most was the behavior of the boa affected by using sheets of moss as cover. I hadn’t thought of it but this echoes my own observations when keeping Pacific boa species . They have a tendency to seek out cover for the most part.
For the more fossorial (burrowing) or terrestrial (surface) dwelling species of Candoia we offer two hide boxes of appropriate size. The snake can go inside the box, curl itself up and have its sides touching the hide box interior. We place a hide box on each side of the enclosure, one on the cool side and one on the basking side. This allows the snake to thermoregulate while being hidden and feeling secure if they so choose.
The last thing on decor is that of a water source. We always recommend a large enough water bowl that the snake can climb in and out of comfortably as well as being able to completely soak within the bowl. Water is to be changed daily and don’t be surprised if your boa often leaves you presents in the water bowl. For some reason, a few of the snakes we’ve worked with had developed the habit of defecating in the water bowl rather than the substrate.
In their native habitats some Candoia begin life eating amphibians and lizards then switching to mammals and birds later on. If you plan to own Candoia in the future, we cannot recommend enough that you demand captive bred snakes. The reason is it can be very difficult to bring in a wild caught snake, used to eating lizards and amphibians, and then getting it to switch over to a rodent diet. I’m not saying it cannot be done, just that it’s best to avoid that situation if possible. Feed appropriate size euthanized mice and rats. We prefer to buy in bulk frozen rodents which we later defrost in warm water.
Candoia and the Future
We really cannot say what the future holds for the Candoia at this point. We do see them growing in popularity albeit slow going, and that may be a good thing. As it is now, current captive breeding is meeting the demands or so it would appear. Candoia are very attractive stout bodied snakes. As babies they can be somewhat nippy, as they grow they become more handleable snakes. As always, please remember that any reptile purchased is an investment in a life which depends on you for its survival. Candoia have been known to live for thirty-five years in a quality captive environment. If you have experience with this species we’d love to hear about your personal experiences below in the comments.
*Special Note: Because I moved to New Brunswick I cannot keep Candoia spp at all in the province. However, two hours away the species is allowed. Ironic isn’t it, I mean what exactly are the environmental impact differences that the two provinces face? Want to find out more about this and other issues facing Canadian Herpetoculture? Join CANHERP.com right now!