Our Beautiful Boa Constrictor
Have you been lucky enough to catch a glimpse of our resident Boa Constrictor Imperator? These snakes are beautiful, non-venomous, and prefer to mind their own business. Unlike the semi-aquatic Anaconda (a specie of Boa), Boa Constrictors (and related species) prefer dry ground and the cover of the rainforest – and so are often seen in our area, especially in the hills above Ojochal, Uvita and Dominical. If you catch a glimpse it will usually be along one of the dirt roads that snake through the foothills of the coastal mountains. The huge snake slithering across the road will be a sight to behold – so stop your car a safe distance away, pull out your camera and let the Boa continue on its journey through our jungles.
BIG AND HEAVY SNAKES
Also called ‘Common Boas’, the constrictors are one of several species of Boas present in Costa Rica – but they are, by far, the most famous. The Boa Constrictor Imperator is the largest and heaviest of snakes found in our country – sometimes reaching a length nearing four meters. But usually, the females reach 2-3 meters in length while the males are a bit shorter at 1.8 – 2.4 meters. The largest of individuals can weight up to 27kg (60 lbs.) but typically the weight of the adult snakes varies from under 10 kg to 15 kg. Some reports speak of massive 45kg Boas – these are not confirmed and often the Boa is confused with the closely related but bigger and heavier Anaconda.
COLOURING
Boas are not the most colorful snakes you will encounter, yet there is a lot of beauty in their markings. Generally exhibiting black, grey, brown and cream coloring, the patterns of the pigmentation create a visually mesmerizing spectacle. Hourglass shapes, triangles, and joining oval patterns extend from the head to the tail. The coloring and patterns create a formidable camouflage which helps the Boa capture the oblivious prey.
RANGE AND FAMILY
The Boa Constrictor Imperator ranges from southern Mexico to north-central Colombia. Other similar Constrictor species can be found in large parts of South and Central America. There is a bit of fuzziness about whether the Imperator is a separate specie of Boa or a sub specie of the Constrictor, although most agree that it is a separate specie – which is confusing as the name of ‘Constrictor’ is still commonly retained, giving the full name as ‘Boa Constrictor Imperator’. Frequent readers of our articles will know that this fuzziness is a very common occurrence with many of our native Costa Rican animals such as the Blue Morpho butterflies or the various local Toucans. For clarity – whether mentioned in this article as Boa, Boa Constrictor or Boa Imperator – we are referring to the single Costa Rican snake specie.
PRIMITIVE SNAKES
The Boas are classified as primate snakes for two main reasons. Firstly, they still retain visible remnants of their hind legs and secondly, they have two lungs. Most snakes have lost one of their lungs and rely on a single lung to breathe because this is the most efficient design to fit their long and slender bodies. Boas still retain two lungs – one lung being non-functional but still present within their bodies.
Another interesting fact is that the Boa, together with the Python, exhibits the XY chromosome structure. All other snakes show the ZX chromosome structure, a relic of a common ancestor.
BEHAVIOUR
The Boas are generally solitary and do not seek other members of their species unless they are looking to mate. When young and slender, they may venture up trees to look for food, but as they gain in age and weight they become earth-bound. The snakes are active around sunset and sunrise but can often be found sunning themselves during the day. Boas live in hollow logs or burrows dug by other animals.
Generally, Boas are not aggressive but may inflict a painful bite if cornered or molested. Bigger snakes can deliver very painful bites as their teeth are large and sharp – however because the Boas are not venomous the bites are rarely dangerous to humans. Interestingly, Boas found in Central America are more aggressive then their South American neighbors – when agitated they hiss loudly and perform multiple strikes. And beware if you see a Boa with milky or blue eyes – this means the snake has recently shed its skin, cannot see well and is likely to be much more defensive!
The Boa is an ambush predator, waiting patiently for its prey to come within striking distance – although when prey is scarce, it may actively stalk and follow animals. The snake quickly strikes at the prey and proceeds to apply the trademark coily wrap. As is common with the constrictors, the Boa then strangles and suffocates the prey before swallowing it whole. The snake wraps itself around the unfortunate animal, forming many coils. It tightens the grip every time the prey exhales, eventually preventing the animal from breathing altogether and causing it to die by asphyxiation. The dinner is then swallowed whole – and the Boas may eat animals much bigger then themselves because they can unhinge their jaws and, as recent research indicates, are able to individually move each rib out of the way as their dinner is swallowed.
There is a theory that the snake induces heart attacks in its prey by increasing the blood pressure with its grip, and another interesting theory that the prey animal dies due to constricted blood flow to the brain rather than by asphyxiation. There is a decent amount of discussion and conflicting information around these topics, but we can agree that the tight coiling around the body of the prey is what dispatches Boas’ dinner. Smaller animals may be consumed without first being strangled.
The menu includes a wide variety of critters such as Agoutis, Coatis, Possums, Foxes, Monkeys, Bats and even baby deer – and in addition to the mammals they also feed on birds, bats (which are snapped near the entrances to their caves or resting areas) and domestic animals such as chickens, goats, baby cows or horses, and even dogs and cats. Of course as the snake gets older and bigger, so does the size of its prey.
Boa give birth to live young – typically between 10 and 60 baby snakes, each between 30 and 60cm long. The baby Boas experience rapid growth during their first year, often tripling their length. The young feed on smaller animals and items of convenience including frogs, mice, eggs, lizards and insects.
THE PET TRADE
Boas are some of the most commonly kept snakes – this is because they can grow to an impressive size, have a calm and relaxed demeanor, can tolerate a lot of handling, and can be bred into a wide range of color morphs – you have probably seen the white and yellow ‘albino’ Boa morph before.
THREATS
The big cats such as the Jaguar can take down the biggest of Boa while their young are susceptible to smaller predators including birds of prey, other snakes, various mammals and even large spiders! But by far the biggest threats to Boas are humans – habitat destruction, collection for the pet trade, hunting (for food, sport, for their skin, the fat that is used in traditional medicine, or due to fear), killing of snakes that ‘get into the chicken coop’, and encounters with cars are very damaging to the Boa populations. In many cases people run them over intentionally, not realizing that Boas are not venomous, do not actively hunt humans and are more scared of us than we are of them. But thankfully, most people reach for their camera, rather than a gun, when they catch a glimpse of a slithering Boa.
OUR NATIVE WILDLIFE
Boas are native to Costa Rica, they area a part of our jungle landscape and play an important role in their environment. While many people fear snakes due to phobias and unjust reputation, it is important to note that these animals mean us no harm and that it is us who chose to live in their environment, not the other way around. So the next time you glimpse a Boa crossing a road or see it coiled up in on your patio, give it time and space, take a photo, and treasure the experience of meeting such a magnificent animal in the wilds of it natural habitat.
Do you dream of living in the midst of breathtaking tropical scenery and amongst amazing animals like our beautiful Boa Constrictor? At RE/MAX WE SELL PARADISE, we list hundreds of tropical properties – homes, land, farms, estates & businesses – all within a stone’s throw of the amazing rainforests, mountains and beaches that make Costa Ballena a world-famous destination. See our property listings here.