LOOK UP to See Costa Rica's Most Amazing Wildlife
The squirrel monkey is the smallest (and cutest?) of Costa Rica’s monkeys and definitely an Icon, but it has an odd habit. Read about it below! Image thanks to Stephen Pekar
Roberta Kravette, editor and travel advisor
By Roberta Kravette
Costa Rica. Just saying the name conjures brightly colored birds and green-tinged sloths, elusive cats, and raucous monkeys. Still, when I look up into a tree’s crown, I expect to catch a feathered being looking back.
But Costa Rica is biodiverse and full of surprises! The eyes staring down may easily belong to one of its many fascinating mammals - and you have to LOOK UP to see them!
One of the twenty most biologically diverse places on earth, Costa Rica is home to nearly 500,000 different wildlife (bird, insect, and mammal) species, 5% of the earth's estimated total. Many are endemic to this small Central American nation.
Thankfully, Costa Rica is also a leader in habitat and wildlife conservation. The country has become a vital haven for hundreds of at-risk species whose tropical rainforest ranges throughout Central and South America are rapidly disappearing from development, deforestation, fire, and climate change. And happily, Costa Rica is also a leader in sustainable tourism.
These are some of my favorite Costa Rican tree-dwelling animals and the best places to (hopefully) catch a glimpse of them in the wild.
Costa Rica’s Sloths
The iconic sloth was at one time thought to be pretty useless. Slow and seemingly not very well-equipped to survive, scientists thought the sloths would disappear. They didn’t. Instead, sloths have become one of Costa Rica’s most popular animals!
You can find two types of sloths here, the brown-throated three-toed sloth and Hoffman’s two-toed sloth. Both are slow, hardly moving at all most of the time. Both, although warm-blooded, have sluggish metabolisms that use solar energy for additional warmth, like lizards.
In general, both two- and three-toed sloths are solitary creatures, living their lives alone. The males go their own way after mating and do not help with child-rearing. Except for the mothers and their young, it is rare to see two sloths in one tree.
Both brown-throated and Hoffman’s can be found in the same rainforests all over Costa Rica, however they are difficult to spot. Taking a guided walk with a naturalist is your best bet.
That Green Tinge is Alive
Both species can appear green-tinged from the algae growing in their fur, a whole ecosystem unto itself, full of micro and macro-organisms, algae, fungi – even moths, mites, and other insects.
The sloths’ in-fur ecosystems may seem a little strange; after all, if something were living in my hair, I would not rest until it was out, out, OUT! But in the case of sloths, the relationships work. The fungi help ward off parasites that cause diseases like malaria and Chagas, the algae is an additional nutrition source, and its resulting green tinge acts as sloth-camouflage from faster-moving, more alert predators. The moths provide fertilizer for the algae. And when sloths make their once-weekly descent down-tree and onto the ground to relieve themselves, the moths lay their eggs in the dung. This fur-based ecosystem is a win for all.
The Brown-Throated Three-Toed Sloth
Sloths are notoriously difficult to spot as they are probably asleep and green-colored due to the algae in their fur. Note the orange patch and stripe denoting a male, brown-throated three-toed sloth. Image: ©Marc Cronje, naturalist and wildlife guide.
7 Fast Facts about Brown-Throated Three-Toed Sloth
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Brown-Throated Three-toed Sloth
Best Place to Find Them
Manuel Antonio Ntl. Park, (south of Quepos, Puntarenas), Corcovado Ntl. Park (Osa Peninsula, Puntarenas Province) , Tortuguero Ntl. Park, (Límon Provence) and see ✓ Trip Tips below for additional information.
When
Most active in the early afternoon between 12 and 6PM.
How
Best results with a naturalist guide in the daytime.
IUNC: Least Concern Bradypus variegatus
1.Brown-throated three-toed sloths can rotate their heads like an owl thanks to 9 cervical vertebrae.
2. The slow-moving sloth can move up to three times faster when swimming and hold their breath for 40 minutes!
3. Their dark eye patches and "smiley" mouths make them look like good-natured bandits.
4. Brown-throated three-toed sloths have a stubby little tail that two-toed sloths are missing.
5. Brown-throated three-toed sloths are about the size of a cat: 9-8 pounds
6. Males vs. females: In their backs, male brown-throated three-toed sloths have a bright orange patch (scent marking gland) with a black stripe.
7. Female brown-throated three-toed sloths help each other give birth, cleaning the new mother and ensuring the baby does not fall out of the tree. The little guy will spend up to 10 months hanging on Mom.
2. Hoffman’s Two-Toed Sloth
Hoffman’s Two-toed Sloth has a distinctive nose, but no dark markings Image:©Jorn Vangoidtsenhoven, Wildlife photographer and Team Member
7 Fast Facts about Hoffman’s Toe-Toed Sloth
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Hoffman’s Two-Toed Sloth
Best Place to Find Them
Manuel Antonio Ntl. Park, (south of Quepos, Puntarenas),
Corcovado Ntl. Park (Osa Peninsula, Puntarenas Province) , Tortuguero Ntl. Park, (Límon Provence).
When
Most active in early evening, an hour after sunset until sunrise. They breed during the rainy season.
Note
Tree limbs, especially where they have access to sun.
How
Take an evening guided tour.
IUCN: Least Concern Choloepus hoffmanni
1. Hoffman’s toe-toed sloths have necks that are shorter than the three-toed sloths, allowing them to tilt their heads back 90-degrees.
2. Look for two toes on the front feet, but three toes on the back feet and no tail.
3. Coloring: Hoffman’s two-toed sloths are light brown, tan, and blond with no dark or outstanding marking. Males and females look alike.
4. Female Hoffman’s toe-toed are sexually mature at 3 years old, the males are not mature until five.
5. Males scent mark from glands around their anus, and the female toe-toed sloth lets out a high-pitched scream to indicate they are ready.
6. When Hoffman’s two-toed sloths descend their tree, they do so head first!
7. Hoffman’s two-toed sloths are mostly nocturnal.
More Monkeys than Humans
Next up are some of the most fabulous monkeys in the New World including one monkey who sleeps all night plus more than 75% of the day and one of only three monkeys on the planet without an opposable thumb. There are four monkey species in Costa Rica, and they are critical to Costa Rica's rainforest habitat. The monkeys feed on a variety of fruit and are important seed dispersers.
All of the country's monkey species are considered vulnerable or endangered, but in spite of this, Costa Rica really is a country with more monkeys than humans.
3. Central America Squirrel Monkey
This clever little monkey is IUCN Listed as Vulnerable to extinction, the pet trade, both legal and illegal is one reason. Image: Greentique Hotels
Let's begin with the smallest - and maybe the cutest. The largest adult Central American squirrel monkey (Saimiri oerstedii) weighs less than 2 pounds (0.9kg). This small monkey has an equally restricted range and is found only on Costa Rica's central and south Pacific Coasts and along the Costa Rica / Panama border. They like secondary and partially logged primary forests.
7 Fast Facts about Central America Squirrel Monkeys
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Central American Squirrel Monkey
Best Place to Find Them
Manuel Antonio Ntl. Park, (on the Pacific coast south of Quepos, Puntarenas), and Corcovado Ntl. Park (Osa Peninsula, Puntarenas Province).
Note
Look up, squirrel monkeys rarely leave the trees.
Conservation Note
The illegal pet trade, as well as habitat loss, has accelerated Squirrel Monkey’s declining numbers.
IUCN: Vulnerable (Saimiri oerstedii)
1. Squirrel monkeys pee on their hands. Why? To mark territory, to cool themselves off, and as part of their hygiene ritual. Oh my!
2. The squirrel monkey's tail is not prehensile – they can only use it for balance, not for grabbing or holding.
3. The squirrel monkey is considered one of the most clever monkeys, it is because their brain is proportionately large compared to its body.
4. Squirrel monkeys live in groups that can range from 25 to 500 individuals!
5. Squirrel monkeys are omnivorous, foraging for fruit, insects, arthropods, eggs, and lizards. They sometimes raid agricultural plantations in deforested areas - this does not make them any friends among farmers.
6. Squirrel monkeys have up to 30 different calls, making for a noisy neighborhood!
7. Central American squirrel monkeys were raised to Vulnerable from Endangered in 1982, but are part of a zoo-based breeding program.
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4. Panamanian White-Faced or White-Throated Capuchin
Capuchin monkeys. Grooming each other helps to bond troupe members. Image: ©Marco Farine
The Panamanian white-faced capuchin (Cebus capucinus) is one of several capuchin species and subspecies, including the black-capped, wedge-capped, the bearded, and the Kaapori capuchin. Although bigger than the squirrel monkey, it is small, about 17-27 inches (not including its tail), the larger male weighs only 8 pounds, and unlike some of the other capuchin species, this species is Endangered.
7 Fast Facts about White-Faced Capuchin Monkey
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White-Faced Capuchins
Best Place to Find Them
Barra Honda National Park (14 miles NE of Nicoya, Guanacaste ) Arenal Volcano National Park (northwest CR),
Corcovado National Park
(Osa peninsula),
Carrillo National Park (Heredia Province),
Monteverde Cloud Forest Biological Reserve (North Puntarenas Province, Monteverde)
Note
Notoriously curious and unafraid of humans, Capuchin monkeys may approach, even “steal” your snacks, etc. Please DO NOT encourage, feed, or touch wildlife.
IUNC: Endangered Cebus Capucinus
1.White-faced capuchin monkeys rub specific plants into their skin as mosquito repellant – and uses tools for defense and forage!
2. White-faced capuchins live in groups of 18-20 individuals called a" troop," or a "cartload," a "tribe," or even a "barrel."
3. Capuchin monkeys are fast! They can move up to 35MPH / 56KPH through the tops of trees to avoid a predator.
4. White-Faced Capuchin monkeys are omnivores eating fruit and nuts, insects, lizards, small birds – and even spiney tree rats.
5.The little black fur cap on their heads reminded early European explorers of Italy's Capuchin friars and gave them their name.
6.Young white-faced capuchins ride on their mothers' backs for six weeks, at which time they become relatively independent, but they are still not weaned for 6 to 12 months.
7. White-faced capuchins are considered second in intelligence only to squirrel monkeys.
5. Geoffroy’s Spider Monkey
Geoffroy’s spider monkey, also called the black-handed spider monkey. Note the bare tip of his powerful tail, the monkeys use their tail like another hand. Image: ©Jorn Vangoidtsenhoven, wildlife photographer and Destination: Wildlife Team member.
Spider monkeys are one of only two New World monkey species without opposable thumbs (the other is the wooly spider monkey, (Brachyteles arachnoides). But don’t worry about these fellows, they make up for that missing thumb with cleverness and a “talented” tail. There are seven different spider monkey species and five subspecies of the Geoffroy's. In Costa Rica, we are most likely to encounter the Ornate Spider monkey Ateles geoffroyi ornatus
7 Fast Facts about Geoffroy's Spider Monkey
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Geoffroy’s Spider Monkey
Best Place to Find Them Corcovado National Park (Osa Peninsula).
Note
Geoffroy’s spider has declined significantly due to hunting and deforestation. They are still sometimes sighted in Tortuguero Ntl. Park, (Límon Provence).
IUCN: Critically Endangered (Ateles geoffroyi) Six of the seven spider monkey species are Endangered; one critically.
1. The spider monkey’s missing opposable thumb gives it their their scientific name, Ateles. It translates roughly to "incomplete" from Greek.
2. Spider monkeys are among the largest New World monkeys, weighing in at up to 24 pounds with long arms and tail.
3. The spider monkey’s tail is its most striking characteristic. It can grow up to 40 in. (102cm) long, much longer than the monkey itself who is only up to 26 in. (66cm) head to rump.
4. The spider monkey’s prehensile tail is so powerful that it can support it whole body: the tip is hairless and has little grooves like our fingerprints.
5. The spider monkey is thought to be one of the most intelligent of the New World monkeys.
6. The highly social spider monkeys tend to split up into small troupes staying together near other small groups. When in danger, the separate troupes come to each other's aid.
7. Spider monkeys eat a wide variety of fruits, nuts, and flowers as well as insects including their namesake, spiders.
6. Mantled Howler Monkey
The largest of the New World monkeys, howler monkeys get their name from, well, howling, and like that other 'howler," the grey wolf, they howl morning and evening to call out territory, locate others of their species, and discourage rivals.
7 Fast Facts about Mantled Howler Monkeys
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Mantled Howler Monkey
Best Place to Find Them
Arenal Volcano National Park (northwest CR),
Barra Honda National Park (14 miles NE of Nicoya, Guanacaste ), Manuel Antonio Ntl. Park, (on the Pacific coast south of Quepos, Puntarenas),
Corcovado National Park (Osa peninsula),
Le Selva Biological Station (Hererdia).
IUCN: Vulnerable, declining. Alouatta palliata
Mantled howler monkeys are listed as endangered on the U.S. Federal List. Due to habitat loss, the Mexican subspecies (Alouatta palliate Mexicana) is classified as Critically Endangered.
1. The distinctive call of a howler monkey can travel up to five miles (8.04 km!) through dense rainforest.
2. The mantled howler gets its name from long guard hairs, or mantle, on its sides. In Costa Rica, these monkeys are sometimes called Golden-mantled Howler Monkeys because of their hair color.
3. Mantled howler monkeys have adapted to their low-energy diet of flowers and leaves by sleeping all night and up to 75% of the day.
4. Family Groups of 10 to 20 individuals usually have a dominant male who mates with multiple females.
5. The famous howls are called at dawn and dusk but communicate among each other with barks, grunts, and "woofs."
6. The male mantled howler monkey is larger than the female and has a white scrotum and a longer beard.
7. Infant Howler monkeys are born silver or golden-brown.
7. Margay
Can cats do pull-ups??? Meet the Margay.
From Tommy Potterton: For years I've been obsessing with tracking and finding this cat. It's not a Jaguar or an Ocelot but the lesser-known Margay
For a relatively little cat, the margay has a huge personality. Often mistaken for an ocelot, this cat is a lot smaller but with longer legs and tail. The margay’s head is proportionately smaller, too, but it is the perfect size to show off those famous big eyes. Also, look for white spots on black ears and 10 to 12 black rings on its tail.
About medium domestic house-cat sized, but with longer legs, the margay weighs between 5.7 - 8.8lb. (2.6 - 4 kg,) and has a body length of 19 to 31in. (48 - 79 cm.) Its thick, balancing tail can be up to 20in (51 cm).
✓ TRIP TIPS
Margay
Best Place to Find Them
Corcovado National Park (Osa peninsula),
Monteverde Cloud Forest Biological Reserve (Puntarenas Province, Monteverde),
Le Selva Biological Station (Hererdia).
Note: Margays are rare and notoriously elusive. Start early, look for groups of feeding monkeys, a margay may be watching, too.
7 Fast Facts about the Margay
IUCN: Near Threatened and declining Leopardus wiedii overall.
In Costa Rica Leopardus wiedii glauculus is considered Threatened
1. Unlike most other cats, the female possesses only two teats. But that is enough for its one- to two-kitten litters.
2. The margay may spend its entire life in the trees, hunting, sleeping, even giving birth in the treetops.
3. The margay is one of two cat species whose ankles can turn up to 180 degrees. The other is the cloud leopard.
4. Their ankle makes the margay remarkably agile and allows it (and the cloud leopard) to climb head-first down a tree.
5. Thanks to the margay’s specially adapted broad, soft feet and agile toes, it can grasp branches equally well with its fore and hind paws,
6. Margays have exceedingly fast reflexes, they can save themselves if falling out of a tree by grabbing it with one hind or front paw and climb up again.
7. The margay can jump 12 feet (3.7 m) horizontally. They are spread-eagle jumpers, flinging out all four legs like a squirrel.
I have to admit that I was way into writing this section before I realized that we had already reached seven animals (and there are even more to discover, too!) But this little guy is way too cute to leave out.
Bonus: Red-Eyed Tree Frog
Costa Rica is famous for its amphibians, and this is the smallest, most colorful, and the only non-mammal on our list. The red-eyed tree frog! Frogs are an indicator species; the fewer threats to the ecosystem, the more frogs will thrive. Red-eyed tree frogs are no different. While the red-eyed frog is not considered Threatened, its rainforest home is under pressure from deforestation, acid rain, and more. The more red-eyed frogs you see, the more hope for the other species that need the rainforest. This guy was spotted in Serapiqui in northern Costa Rica.
Fast Facts for Red-Eyed Tree Frog
✓ TRIP TIPS
Red-Eyed Tree Frog
Best Place to Find Them
Monteverdi Cloud Forest Biological Reserve, Puntarenas Province, Monteverde.
Le Selva Biological Station, Hererdia,
Tortuguero Ntl. Park, (Límon Provence.)
Manuel Antonio Ntl. Park, (on the Pacific coast south of Quepos, Puntarenas).
Note
Look for red-eyed tree frogs at breeding season when males gathered around water sources call females out of the trees; the breeding aggregation can number in the hundreds.
IUCN: Least Concern Agalychnis callidryas
1. Female red-eyed frogs are larger ( up to 3 inches) than the male. (2inches), they need to be for the mating process. The female will carry the male on her back until the egg-laying and fertilization process is complete.
2. Look for them in humid lowland rainforests near water sources like rivers or streams. Check hiding places in a bromeliad, or under tree leafs, or clinging to a tree’s limb or trunk.
3. Red-eyed tree frog is a carnivore: eating primarily insects like crickets, grasshoppers, flies, moths, and occasionally a smaller frog. The tadpoles dine on fruit flies and pinhead crickets.
4. The red-eyed tree frog’s famous eyes are a defense mechanism called “startle coloration.” The nocturnal frog sleeps during the day, eyes hidden by closed lids, looking like a green mound. But, it quickly opens them when it feels the presence of a predator, momentarily startling it, giving the frog the seconds it needs for a fast get-away.
5. The bright lime-green body of red-eyed tree frogs can become dark green or even red according to their mood. Their bellies are white, and their sides are blue with white bars, and the feet are bright red or orange.
6. Their perpetual “smile” and bright colors make red-eyed frogs look like a friendly bunch, however, all that cuteness is hiding a slightly toxic exterior. Not poisonous enough to kill most predators, but sufficiently distasteful to make them look elsewhere for their next meal.
7. Females lay their eggs on leaves overhanging water. After about a week, the new tadpoles fall in. Tadpoles can “decide” to hatch themselves prematurely if they sense danger but will not fully mature for one to three years (dependent on food supply.)
Costa Rica’s 7 Iconic Animals in Trees are waiting for you. Mantled howler monkey image by ©Marc Cronje wildlife guide and naturalist.
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This article was first published in Dec. 2020 and updated June 2024.
