Introduction to Boas
If you’re new to the world of boa constrictors you may not be aware that there are lots of different types of “boa constrictors”. Typically what you see in a pet store or on television is referred to as a “boa”, “boa constrictor”, or “red-tailed boa”. Chances are pretty good that in all these cases the boa in question is a Boa imperator, commonly shortened to BI in the reptile world. Without getting into too much detail, this species of boa constrictor is found throughout Central and South America and is the most common type of boa in the pet trade. There are a lot of other species, sub-species and localities of boas! True “red-tail boas” belong to the sub-species Boa Constrictor Constrictor (BCC) and generally have brick red-tails and get larger than BI’s. There is a fairly good breakdown of the boa species and sub-species here – Reptifiles – if you’re interested in learning more. Also just to note, up until a few years ago the Boa imperator was actually classified as a Boa Constrictor Imperator or BCI for short. Because this change is relatively recent it’s still very common to see Boa imperators referred to as BCI’s or Boa constrictor imperators.
The Boa imperator species is found throughout Central and South America, because of this extensive range there is a lot of variety within the species. Different localities can vary in size, color, and temperament. Many of the “dwarf boas” are found on islands or specific areas in Central America, and will stay between 4-6ft depending on the locality. If getting a dwarf boa that stays a certain size is important to you, then you should make sure to go through a reputable breeder who specializes in locality boas. If you’re interested in learning more about the different boa species and localities, Vin Russo’s book, The More Complete Boa Constrictor, is probably the best breakdown. It also includes information on most of the available boa morphs.
General Care Guide
The adult size of the boa constrictors varies based on species, locality, individual genetics, and feeding schedule. Most boa imperators in the pet trade are locality mutts, they have Colombian and various Central American localities. Unless you get your boa from a reputable breeder who specializes in specific localities, assume your boa is a locality mutt. Most BI morphs are locality mutts, females are usually 6′-8′ as adults and males are 5′-6′. Sometimes individuals will be larger than this but it’s pretty rare. Pure Colombian localities might be larger, but again, you’ll know if you have a pure Colombian because the breeder will charge a premium for this and make it very clear.
The true red tail boas, Boa constrictor constrictor’s, AKA BCC’s, are usually larger than Boa imperators. Both in length and thickness. But they do grow slower and are most sensitive to being powerfed/overfed than Boa imperators. Slow and steady is a good policy when it comes to feeding boas, especially BCC.
The term “dwarf boa” is thrown around in the industry a lot and means different things to different people. In general, most of the Central American localities are smaller than their Colombian counterparts. I own several pure El Salvador Boa imperators and all of my adults are about 4ft, including the females. Some CA localities will be larger than this, but many will stay under 6ft. There are also different species like Boa constrictor amarali and Boa imperator longicauda, that usually stay under 6ft.
Baby Boas (0-2 Years Old)
Young boas do pretty well in tubs because the smaller space provides more security for them. This doesn’t mean that you can’t put them in larger cages, just be aware that if you take this approach you need to provide lots of hides and pay attention to their behavior. I’ve had some young boas that have thrived in larger cages and others that got stressed out and had problems like regurgitation or refusing food. I usually house my younger boas in tubs that are 24″ x 14″. They have two hides, one on the hot side and one on the cool side, something to climb on, and a water dish.
Sub-Adult Boas (2-4 Years Old)
This is usually the age when I upgrade my boas to cages, but it’s possible to keep them in tubs. At a minimum, I give them a 2’x3′ cage, 2`x4′ is better because this will satisfy their cage requirements for longer. A tub is fine as long as it meets this footprint. Most species of “boa constrictor” (Boa imperator, Boa constrictor, Boa sigma, etc.) are semi-arboreal and will use any height they are provided. In most cases, male boas will be fine in a 2’x4′ cage their entire lives. Females will usually need a larger cage unless they are from a dwarf locality or are from a smaller species like Boa i. longicauda.
Adult Boas (4+ Years Old)
This is the age when you usually need to start considering the permanent housing for your boa. Adult males will often be fine in a 2’x4′ cage but it’s possible they’ll need something larger. Females almost always need a cage that is at least 2’x6′. The more height you can give them the better, not only for our benefit but it will make cleaning the cage easier. There are tubs that can meet at least the foot print requirement but they’re pretty expensive, so unless you’re planning on breeding and housing a lot of boas, getting a good PVC cage from a company like Animal Plastics or a similar manufacturer is a good option.
Temperature & Humidity
Boa constrictors have pretty straight forward requirements in terms of temperature and humidity. They should be provided a hot spot of 88-90 degrees and the cool side should be around 80 degrees. Humidity should usually be in the 60-70% range. Different localities and species might have slightly different requirements, so do your research if you’re interested in one of those. When it comes to breeding boas, temperature, humidity, and light cycles also play a significant role and varies based on species and locality. Vin Russo’s book, The More Complete Boa Constrictor, provides a lot of information about the different requirements of each species/locality.
General note on feeding boas. There is no exact schedule to feeding boas, and there is some wiggle room based on the outcome you want. Meaning if you want to keep your boa on the smaller side, you can feed smaller meals to accomplish this in a healthy way. If you want a boa on the larger side, you can feed slightly larger meals to accomplish this. Do your research and pay attention to your particular boa. It was mentioned previously, but slow and steady is always a good approach. Boas take a long time to grow and patience is important if you want your boa to have a long and healthy life.
Also, most boa constrictors have strong feeding responses and are extremely easy to switch over to frozen/thawed. I start all of my babies on frozen/thawed and very rarely have a problem. There are some localities that can be finicky at first, but I personally have never encountered an adult boa that wouldn’t eat frozen/thawed. Given that adult boas are usually eating rats, it’s highly advised that you give them frozen/thawed or pre-killed, because a live rat can do a lot of damage to a snake.
I mostly feed my snakes a diet of mice/rats, but I do rotate in other prey items like chicks and quail. In the wild, boas actually eat a lot of birds which have way less fat than the rats we feed them. Some of my large females will get appropriately sized small rabbits once or twice a year, but this isn’t necessary and should be reserved for large females. When I feed a large meal like this, I typically wait 6 weeks before feeding again.
Lastly, there is some argument to be made about changing your feeding schedule throughout the year. In the wild, most boa constrictor species have evolved to survive feast/famine situations. They have slow metabolisms and do not handle being fed multiple meals in a short span of time. Some people, like Vin Russo, suggest that they actually grow better if you let them go a few months without eating, which is more similar to what they would do in the wild. Feeding schedules can/should also be changed when you’re attempting to breed. Personally I follow the feeding guidelines below for spring and summer, when fall comes I switch everyone except that years babies over to every 30 days, and no one gets fed from mid-December to early February, except boas under a year old.
Baby Boas (0-1 Years Old)
Most baby boas can be started on mouse hoppers and move up from there. By the time my boas are a year old, they are usually eating small mice (15-20g).
Feeding Schedule: Every 10-14 Days
Baby-ish Boas (1-2 Years Old)
Boas do a lot growing in their first couple years so they’ll progress from one size to another pretty quickly. I prefer to feed mice at first and then upgrade to rats. So they’ll go from small mice to adult mice and then when they’re ready, small rats. By the time my boas reach two years old, they’re usually eating small rats.
Feeding Schedule: 14-21 Days
Sub-Adult Boas (2-3 Years Old)
This is usually when the size difference between males and females becomes more apparent, particularly with Boa imperators. Females can usually be upgraded to medium rats at this age, once small rats are no longer leaving a lump. Males might continue to be fine with small rats.
Feeding Schedule: Every 14-21 Days
Adult Boas (3+ Years Old)
By this age, most male Boa imperators will be ready for medium rats and they will usually be fine on these for the rest of their lives. Females will usually be ready for large rats around 4 years of age and technically can be fine on those for the rest of their lives. My larger females, once that get over 6ft, I usually give a few large meals a year which is usually an appropriately sized small rabbit. XL rats should be avoided because they’re super fatty.
Feeding Schedule: Every 21-30 Days*
When feeding a large meal like a rabbit, more time should be added between meals.