Fauna
Costa
Rica's boasts a profusion of zoological riches, and rightfully so. The National
Institute of Biodiversity, in an attempt to identify every plant, animal and
insect species, has approximated that within the borders of this small isthmus
at least one million species exist. The great variety of
ecosystems makes it possible for so many different creatures to live in
close proximity to one another.
Amphibians
Rainforest Amphibians
Some of the most beautiful and unique creatures of the Costa Rican rainforest can be the deadliest. Most rainforest amphibians have toxins that are secreted from their skin, but the toxicity of the poison varies significantly with the species. Some amphibians possess toxins that simply produce a mild skin irritation, while others can be fatal. They infect their prey and unsuspecting bystanders by two modes of infiltration: toxins may be ingested through pores in the skin or through the mucous membranes of the mouth and throat. Therefore, while visiting Costa Rica, do not for any reason touch these creatures! You shouldn't have much trouble spotting them; rainforest amphibians are either entirely brightly colored or have bright patches somewhere on their bodies.
Poison Dart Frog
The brilliantly red-colored poison dart frog resides high in the trees of the rainforest. Its skin glands secrete a potent toxin that resembles sweat, but that, if ingested, will poison its hungry adversary. The bromeliad's cisterns serves as the frog's breeding grounds, a perfect place for tadpoles to develop safe from predators. After a two-month gestation period, the adult frogs emerge from their plant shelter armed with their toxic shield.
Reptiles
Sea Turtles
Five of the seven species of sea turtles that cruise the world's oceans come to Costa Rica to lay their eggs. From July to October each year, hordes of Green sea turtles flood the Caribbean coast near Tortuguero National Park. Other endangered species are known to inhabit the area when the green sea turtle is away including the loggerhead, the hawksbill, and the world's largest reptile, the giant leather-back. The latter, which can weigh as much a ton and grow to about ten feet long, can be found in greater numbers on the Pacific coast. From October to April, hundreds of leatherbacks come ashore at Playa Grande in Nicoya.
Crocodiles
Two
kinds of crocodiles are found in Costa Rica. What are commonly identified
as crocodiles are large beasts with lengths reaching up to 13 feet! They generally
loafing along the muddy banks of rivers and estuarine waters of the Northern
Region and the Caribbean coast.
The
smaller species is referred to as the cayman. This variety averages
a length of just less than three feet and can be observed chillin' in creeks,
ponds, mangrove swamps, and beach lowlands. They are commonly found in and
around Coravado National Park.
Iguanas
Iguanas are ubiquitous throughout Costa Rica. The spiny-tailed iguana is green, but males turn orange during their mating season in order to boost their sex-appeal. The tree-dwelling iguana inhabits both the dry and wet lowland forests, and reaches a length of about three feet. This species appears quite formidable as it is covered in scaly armor. However, while they might seem fearsome. they are quite harmless to humans.
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| Iguana |
Boa Constrictor
The boa constrictor is a long, plump snake that reaches to almost 12 feet in length and is patterned with dark squares on its light brown or gray body. Much of their time is spent waiting for unsuspecting prey, such as lizards, opossums, deer, and even ocelots. Upon attack, the boa will grab the victim with its mouth, gripping it with its fangs, and crush the prey as it wraps around it. Once the prey is immobile, the snake swallows it head first.
Fer-de-lance
The fer-de-lance, a member of the viper family, is the most dreaded venomous snake species in Costa Rica. And this fear is not unsubstantiated; the fer-de-lance is responsible for 75% of Costa Rica's snake bites and almost all deaths. This formidable species is brown and black with a white "X" pattern along the length of its back. Their camouflage effectively hides them among the twigs and leaves of the rainy jungle, enabling them to go undetected by birds, small mammals and other potential prey. If disturbed, they will attack anything that moves. Therefore, upon encountering this volatile snake, try to stay calm and be perfectly still.
Eyelash Viper
The eyelash viper is appropriately named after a visor-like scale that extends beyond their eyes. They are small snakes (usually less than three feet long) and come in a variety of colors: green, gray, brown, rust, and light blue with a darker diamond on their back. Eyelash vipers position themselves above the jungle floor, and are commonly observed hanging from tree branches. They are highly venomous claiming the lives of about four people each year in Costa Rica.
Because the snakes in Costa Rica are well-camouflaged and rather wary of humans, they are not easily observable. The best way to get up close without putting you or the snake in danger is to visit a serpentaria, like the ones in Parque Viborana near Turrialba, in San José, and in Grecia.
Insects
Flower Mite
These microscopic insects hitch rides in the nostrils of hummingbirds.
Rhinoceros Beetle
Named for the rhinoceros-like horn on its head, this well-known beetle can grow to be 3 inches long.
Morpho Butterfly
The morpho is very large; about the size of a compact disc. It usually has neon-bright blue wings, though colors can vary in subspecies.
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| Morpho Butterfly |
Owl Butterfly
Larger than the morpho, the owl butterfly reaches a size of approximately 6 inches. Its name derives from the fact that its coloring under its wings resembles owl's eyes. The butterfly flashes these "eyes" when it is threatened.
Ants
Of the thousands of ant species present in Costa Rica, the leaf-cutter ant is probably the most remarkable. This species farms mushrooms underground, and uses chewed leaves to nourish the crops. Army ants march around in large number, sweeping through over the land, and destroying most everything in sight. The Aztec ant lives in a complex and perfectly mutual harmony with the cecropia tree. They ants live in the hollow trunk and branches of the tree and searches the limbs for epiphyte seeds and seedlings, which they discard over the side. The cecropia tree benefits greatly from this arrangement because the weight of the epiphytes would surely overwhelm the weak-limbed tree. On the other hand, cecropias produce fat and protein-packed capsules at the tips of their leaves, providing great nourishment for the Aztec.
Birds
Quetzal
The quetzal is Costa Rica's most famous bird. These cloud-forest dwellers are fairly large and are primarily green in color. To attract mates, males don a two-foot long wispy tail. Despite their brilliant coloration, the quetzal is relatively inconspicuous; they reside in the upper canopies of trees, and they remain very still while hunting insects and small frogs. Often revered by Ticos as a venerable symbol of freedom and independence, the quetzal can only survive in the wild and cannot exist in captivity.
Toucan
These
black and yellow birds have characteristic large keel-shaped beaks that display
myriad colors. Some beaks are simply yellow and black with accents of red,
while other beaks can be a splashy rainbow of colors. Toucans are
prevalent throughout Costa Rica.
Bare-Necked Umbrella Bird
The males of this species is large and black with fluffy headdresses. To attract their female counterparts, the males will inflate their bright red featherless throats.
Three-Wattled Bell Bird
This bird gets its name from its bell-like voice and the three wattles of skin that flop over its beak. They eat the same avocado-like fruits as the quetzal and migrate to much lower elevations after breeding in the cloud forest.
Hummingbirds
These tiny birds survive on a diet of nectar. They are specialized to hover over flowers, consuming the sweet sustenance while donating their services as a pollinator. Possessing unusual wings that that are able to rotate about their shoulders, hummingbirds are able to fly in all direction. Almost one-fifth of the 330 species of hummingbirds in the world are found in Costa Rica.
Oropéndolas
These birds are large and relatively colorless with the exception of their yellow tails. They weave long sac-like nests on dead tree branches.
Scarlet Macaws

The
scarlet macaws used to live throughout the lowlands of Costa Rica, but deforestation
and poaching have restricted the few remaining birds to the Osa Peninsula
and Carara Biological Reserve. These birds are monogamous and mate for life.
Green Macaws
These beautiful birds are facing a difficult challenge as their home forests are being destroyed at a distressing rate. It's been estimated that their habitat has been reduced by 95 percent. These birds nest in almendro trees, which in past years have been ignored by loggers because of their exceptionally hard wood. Recently, however, new technology has made processing of the ultra-hard almendro possible.
Water Birds
Costa Rica has a great variety of waterbirds. The commonly-spotted kingfisher, of which there are six species, has a short neck, large head, and a sharp bill which is adapted to diving for unsuspecting aquatic prey.
Seasonal Birds
Costa Rica is a part of a relatively narrow land bridge that links North and South America, so it serves as an interim transition point for meandering populations migrating in either direction. Roughly 25% of Costa Rica's more than 850 bird species are seasonal guests, migrating to to escape harsh winters and food scarcity. Many of these birds make long and arduous journeys over land and sea. Hawks, eagles, falcons, hummingbirds, warblers, finches, swallows, flycatchers, orioles, and tanagers are some of the birds that seek the accommodating climate of Costa Rica.
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| Pigeons |
Cowbird |
Mammals
Jaguar
The largest of Costa Rica's carnivores is the jaguar. Preferring to roam the land in the absence of humans and requiring a great amount of space to accommodate their hunting behavior, each adult jaguar needs about 100 square miles of forest reserve in order to optimize its chances of survival. Unfortunately, as humans claim more territory, jaguars have been forced to retreat into crowded, thus reducing the gene pool and increasing the occurrence of genetic mutations.
Other cats to keep your eye out for include ocelots, pumas, and the rare margays and oncillas (both spotted like cheetahs), as well as the dark brown jaguarundis.
Sloth
Named for the sluggish rate at which these peculiar mammals move, the sloth's leaf diet generates very little metabolic energy. In addition, they possess much less muscle tissue compared to other mammals. Using their strong arms and long-hooked claws, they hang upside down from trees, slowly scooping leaves into their mouths. The sloth has few predators. It grooms rarely, so algae, a natural camouflage, covers the beast. In addition, its flesh tastes bad, even to the most indiscriminate of eaters.
Tapir
The tapir, in spite of it's appearance and size, is a fast creature. Their feet are adapted for running on the muddy surfaces, such as the often muddy floors of the rainforest. These mammals are facing distinction, however. They have long been the prize of Costa Rican hunters.
Monkeys
These
highly intelligent creatures are the most social of animals that inhabit the
forest. There are four types of monkeys in Costa Rica. The small, omnivorous,
black and white-faced capuchin monkey are commonplace around Manuel
Antonio National Park, taking center stage as they showoff for visitors. The
large black howler monkey is the most common species in Costa Rica.
They are well-suited for their name as many alarmed visitors might know; their
roars and howls can be heard resonating throughout the forest. Not to fear,
however, these monkeys are herbivorous. The blond-chested spider monkey
features a long, prehensile tail with a fingerprint-like imprint at the end,
perfectly adapted for gripping. They are very agile and can leap up to 30
feet from tree to tree. This is a solitary creature that prefers a life with
little social contact. On the other hand, the diminutive squirrel monkey
is a highly social critter that lives in bands of up to 40. This variety inhabits
the Pacific lowland area.
Coati
With
their long, bushy, ringed tails and masked faces, the coati, a species
of the raccoon, is one of the most identifiable mammals in Costa Rica. Visitors
to the country might see this ubiquitous omnivore scurrying about the canopies
of trees, or hunting for tarantulas on the forest floor. Females are very
social and live together in groups of up to 30, while the males are solitary.
Other members of the raccoon family which might be harder to observe are the smaller, nocturnal, tree-climbing cousins of the coati; the olingo, cacomistle, and kinkajou.
Collared Peccary
These pig-like creatures are highly social; they live in groups of up to 35 and sleep together to conserve heat. Salutations are often peculiar. They greet one another by rubbing their heads against the scent glands near their tails.
Agouti
This mammal resembles a brown, oversized, tailless squirrel with long slender legs. Unfortunately, this unique species has a long history of being hunted for its flesh, and it is now endangered.
Anteater
Three species of anteaters live in Costa Rica. They are highly specialized creatures, possessing the ability invade anthills with their long, sticky tongues, scooping out the unsuspecting ants and ingesting them.
Manatee
These marine herbivores resemble tuskless walruses. They have a unique shovel-shaped flat tail. This endangered species inhabits the watery recluses of Tortuguero and the adjacent Refugio Nacional de Vida Silvestre Barra del Colorado.
Humpback Whale
Humpback whales gather seasonally to feed and mate in the warm waters of Bahía Ballena.
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| Cebu |
Cow |





