Everyone’s heard of arachnophobia.
But have you heard of ophidiophobia? Probably – without even realising.
Ophidiophobia is the intense fear of snakes and is one of the most common phobias of humankind.
But, like sharks, the fear is often taken out of proportion.
Snakes play an important role in maintaining the balance of the ecosystem. They are important predators of disease-carrying animals, such as bats and rodents. They are also a valuable food source for a variety of predators, such as birds and mammals.
So, what types of snakes are native to Costa Rica?
Of the 3,000 species of snakes found on planet Earth, approximately 140 can be observed in Costa Rica. Of these, 22 are thought to be venomous; most of which belong to the viper family. Common snakes of Costa Rica include the boa, fer-de-lance, coral, eyelash viper, and more.
In Costa Rica, snakes can be found at all elevations in tropical and subtropical forests. However, most species can be found below 1,500 meters.
Read on to discover the types of snakes that are part of the Costa Rica wildlife!
1. Boa Constrictor
Related to the anaconda, a type of animal found in lakes and marshes, the boa constrictor is a large, non-venomous snake found throughout Central and South America. They are relatively widespread in Costa Rica, especially in drier regions, such as the Northern province of Guanacaste.
They belong to a group of snakes that constrict (surprise, surprise), rather than envenomate their prey. They coil their body around their victims, which happen to be large animals, such as deer. However, they have been known to prey on other apex predators, such as caimans. As their prey struggle to escape, the boa tightens its grip until eventually, their prey succumbs to asphyxiation.
Growing to lengths of up to 6 meters, the boa constrictor is one of the largest snakes in the Americas. Their distinct cryptic patterning of light and dark brown patches allows them to go almost unnoticed on the forest floor.
Boa constrictors are active both at night and during the day. They can be found up to 1,000m and can be seen in a variety of National Parks across Costa Rica, such as Santa Rosa and La Selva, and Carrara.
2. Fer-De-Lance (Terciopelo)
Forget jaguars and crocodiles – these are like child’s play compared to the terciopelo.
The terciopelo belongs to the pit viper family, and is one of the largest extant species in the family alive today. Their large size means that they are capable of delivering a large amount of venom – more than king cobras and black mambas.
However, it’s not the toxicity that people fear (well, I guess it is, but we’ll explore that in more detail below), it’s their behaviour. Let me explain.
Unlike other species of snake, which prefer to remain hidden or retreat when threatened, the terciopelo often stands its ground and attacks if threatened.
This wouldn’t be a problem, if they were found deep in the forests. Unfortunately for humans, the terciopelo can be found in human-disturbed areas, as well as farmland and gardens all across Costa Rica. They are cryptically coloured, often a mottled brown colouration, allowing them to effortlessly blend into their forest floor habitat.
To make matters worse, the terciopelo doesn’t just bite once. They repeatedly strike their victims, delivering fatal quantities of venom. The only saving grace is that the potency of said venom is much weaker than other species of snake. So, whilst they can deliver more venom in a single bite, the potency is diluted.
But don’t get any ideas. The terciopelo still has a deadly venom, and is one of the biggest killers in Costa Rica. Proceed with caution.
3. Central American Coral Snake
Beautiful, yet deadly, the Central American coral snake can be found mostly at night in dry and humid regions of Pacific Costa Rica.
The coral snake has a potent neurotoxic venom that is capable of causing muscle weakness, paralysis and even respiratory arrest. And that’s the effect it has on a fully grown human – imagine the devastating effects the poison has on the small vertebrates, such as lizards and other snakes, on which the coral snake preys upon.
However, they use an effective warning system that allows potential threats to exhibit caution.
It’s like someone holding up a giant sign saying “dangerous human, will attack if approached”. But, instead of holding a sign, the coral snake wears its sign of brightly coloured banding.
This is not uncommon in the Animal Kingdom. Many dangerous, or noxious, species advertise their toxicity in the form of bright colours. This is known as aposematism. Many non-toxic species mimic these toxic species. As a result, we can find lots of animals that look the same as each other.
In the case of the coral snake, they have evolved red, yellow, and black banding that warns any potential predators to back away.
4. Eyelash Viper
For any snake enthusiast out there, the eyelash viper has to be high up on the list of bucket-list snakes.
Although highly venomous, it is one of Costa Rica’s most iconic snake species.
Not only are there a variety of colour morphs – from vibrant yellow to mossy green – the eyelash viper has found fame in the form of their eyelashes.
A snake with eyelashes, now that’s a sight. Oh, how beautiful it would be.
Alas, the eyelash viper does not have mammalian eyelashes. Rather, they get their name from modified eye scales which look like small horns. It is thought that the “eyelashes” aid in camouflage, breaking up the snake’s outline among vegetation.
A species of pit viper, the eyelash viper locates and hunts its prey using heat. When prey, such as small rodents and birds, are detected, they strike and deliver a fatal dose of neurotoxic and haemostatic venom from their needle-like fangs.
Thankfully, eyelash vipers are rarely aggressive, and human casualties are few and far between.
Some of the best places to see the eyelash viper in Costa Rica would be on the Caribbean side, in National Parks such as Tortuguero and Cahuita (I have seen them in Cahuita). However, with the right guide, or just sheer luck, you may also be able to see them on a low-lying branch in Arenal or Corcovado.
5. Parrot Snake
An ode to the brightly coloured parrots, or loras, that can be found across Costa Rica, the parrot snake is a vibrant green snake with large yellow eyes and striking black markings.
They are a long and slender species of snake, allowing them to hunt for frogs and smaller reptiles in hard-to-reach places, such as bromeliads. They are also well adept at climbing, and are commonly sighted in trees and vegetation.
Originally thought to be non-venomous, this myth has now been debunked. Parrot snakes are mildly venomous – which may explain why they are so brightly coloured. When dangerous animals advertise bright colours as a warning to potential predators, we refer to that as aposematism.
Thankfully, the venom has little to no effect on humans. They are a species of rear-fanged snake and teeth are found quite far back in the mouth. Only their small vertebrate prey are unlucky enough to feel the full effects of the venom.
The parrot snake is a common species of snake found in Costa Rica, with sightings in Corcovado, La Selva, and Manuel Antonio National Parks. However, due to habitat loss, their populations are declining.
6. Lyre Snake
Named after the triangular musical instrument, a lyre, the lyre snake has a distinct V-shaped pattern on its head and across its body.
Although relatively widespread across Northwest Costa Rica, the lyre snake is seldom seen. During the day, it wedges itself within rocky crevices. At night, the lyre snake becomes active.
Although the lyre snake is capable of delivering a venomous bite, the haemorrhagic venom itself is not very effective – especially against birds and mammals. Whilst the venom may be sufficient to subdue small lizards, constriction is needed when the lyre snake hunts birds and mammals.
Despite their large size, growing to lengths of over one meter, to us humans, the lyre snake poses no threat.
7. False Coral Snake
What’s better than being a devastatingly deadly snake?
Pretending to be a devastatingly deadly snake!
Some animals look the same. The false coral snake, an absolutely harmless species of snake, looks remarkably similar to the deadly coral snake.
In nature, this is a relatively common biological occurrence. Known as Batesian mimicry, a completely harmless species mimics the colouration, pattern, or even behaviour of a dangerous species.
A cleaver evolutionary tactic, the mimic gains protection as predators associate its similar appearance with a noxious animal and leave it alone – a significant energy-saving mechanism. However, this adaptation can only occur in areas where the model, or dangerous animal, is more numerous than the mimic.
In Costa Rica, the false coral snake displays the same black, yellow, and red coloration as the highly venomous coral snake. However, the order is ever so slightly different. As the famous saying goes: “Red touch yellow, kill a fellow. Red on black, friend of Jack”.
Of course, don’t go around getting up close and personal with any snakes you’re not familiar with. After all, there are certain colour morphs that can be deceiving.
Without venom, the coral snake uses the process of constriction to kill prey, such as small rodents.
8. Yellow-Bellied Sea Snake
When you think of some of the most venomous snakes on our planet, what comes to mind? Is it the black mamba? The cobra? The inland taipan?
Of course, all would be correct. However, one of the most toxic snakes on Earth can actually be found in the water off the coast of Costa Rica.
Gram for gram, the yellow-bellied sea snake is one of the most toxic animals on the planet. Just 0.07mg is considered a lethal dosage. The venom is highly potent and contains a dangerous cocktail of neurotoxins and myotoxins, the latter of which can lead to muscle necrosis and paralysis.
Fortunately, the fangs of the yellow-bellied sea snake are small – no larger than 1.5mm – and are somewhat inefficient when it comes to delivering venom. As such, they are not considered a threat to swimmers.
In fact, I have handled one myself.
Whilst patrolling a beach in Northwest Costa Rica, multiple sea snakes had been washed ashore. Their paddle-like tail, whilst extremely effective for propulsion in the water, rendered them completely stranded on the shore.
Using a stick and, most importantly, ensuring the head was a safe distance away from me, I manoeuvred the snakes just past the breaking waves and watched them swim away to safety.
Sea snakes can survive on land. However, they spend 90% of their life cycle in the water – even copulation is in water. The only time a sea snake will come to land will be to lay eggs.
9. Neotropical Rattlesnake
With its maraca-like rattle, rattlesnakes are one of the most iconic serpents of the Americas.
Although they are often seen as a North American desert-going species, often portrayed as such in the Wild West movies, rattlesnakes can be found throughout Central and South America.
Costa Rica is no exception. In the hot, dry region of Guanacaste, the neotropical rattlesnake can be found – often in areas of dry grassland or scrubland.
A member of the viper family, the neotropical rattlesnake is a medium-sized snake, growing to lengths just shy of 2 meters. Like other vipers, it has a stocky body, with a prominent zig-zagging pattern across its cryptically coloured dorsal side.
The neotropical rattlesnake is nocturnal. To locate prey, such as rodents, the rattlesnake has two heat-seeking pits located between its eye and nose. These heat pits can detect infrared rays given off by a warm-blooded animal. However, the neotropical rattlesnake is mostly an ambush hunter. After all, who has the time and energy to track down a speedy mammal?
The rattlesnake will remain motionless on active trails of small rodents. If a small mammal in Costa Rica wanders too close, the rattlesnake will strike in the blink of an eye, delivering a fatal dose of venom.
Capable of becoming fatal to humans, the venom of the neotropical rattlesnake contains both haemorrhagic and neurotoxic properties. In other words, the venom attacks both the muscles and nervous system of prey.