While I admit that this is a bird blog..I know that I’ve veered a few times away from the feathered kind for the sake of pure natural curiosity which I’m sure all of you can identify with. Thus, today’s blog post is going to get a bit furry–but don’t worry, we’re still up in the branches, hiding among the leaves. Perhaps even eating them..
So among the 450 acres of primary rainforest which make up Saladero Ecolodge, surrounding our 30 acres of gardens, we are often visited by the arboreal mammals that carry out life high in the trees.
In the primary forest here at Saladero, we often get great sightings of three of the four different species of monkeys that exist in Costa Rica: the Mantled Howler Monkey, the White-headed Capuchin (formally known as White-faced) and the Geoffroy’s Spider Monkey. The itty bitty Squirrel Monkeys can be seen just north of us in the rich mangrove forests of Rio Esquinas just a 25 minute kayak toward the top corner of the Golfo Dulce, but I can’t explain why they don’t appear to be over on our side of town.
Anyways, whether they’re near or far, we always know where the howlers monkeys are because, each and every morning, they burst forth into their impressive, otherworldly bellows before the sun has even properly risen. I like to call them our battery-free Costa Rican alarm clock.
Male howlers (called “Congos” in Spanish) sport a massive pouch under their chin and their roar can be heard more than a kilometer away. This is thanks to an enlarged hyoid bone in their throat which helps amplify the call, making them the second loudest mammal in the world, beaten out only by the monstrous Blue Whale. Congos will often call at sunrise or sunset as a means to communicate within the troop and let other howler troops know not to come into their territory. They’ll also howl in response to rain or if startled by loud noises including planes flying overhead or humans nearby. Sometimes they’ll howl in the middle of the night and alone in my tent cabin I wonder what’s caused them to do so, be it a bad dream or an unwanted visitor..
Howler monkeys are folivores, meaning they eat primarily leaves, but they will also forage upon fruits and flowers on occasion as well, depending on the season. When the fig trees are fruiting, these monkeys can be seen eating both the leaves and fruits at the same time in a single fig tree. The fruits already containing maggots up high in the branches are prized for their protein value. Howlers will also feed upon flowers from trees during the dry season.
Since most trees have developed a toxin to resist becoming completely defoliated by these and other folivores, the monkeys can’t stay in one tree for too long because consuming too many of the leaves can be harmful to them. Therefore, as they forage, you might observe them moving from tree to tree, stopping to munch for awhile on one species before carrying on along to another. The monkeys make a special effort to hone in on the younger, more supple and nutrient-rich leaves in each tree over the harder-to-digest mature leaves. Nonetheless, this primarily leaf-based diet results in the need to rest and digest a good part of the day in order for their metabolism to break down the tough leaf fibers.
When I had the fortune of climbing 20 meters up (fully supported by a complex rope system thanks to Ruthmery Pillco Huarcaya, a biologist at Osa Conservation who sets up tree-top camera traps), I found myself at eye-level, just another dozen meters away from a couple of howlers. But didn’t matter how hard I howled (I tend to talk to wildlife..), because they were in full food coma. Thus, the only response I got was one suddenly swatting away at a fly by one hunched over individual, as if I were just as annoying.
Another of our furry friends from above include the capuchin monkeys, known as “Cariblancas” (white-faced) in Spanish. Capuchins are omnivores, meaning they live on a much more nutrient-rich diet of fruit, nuts, insects and crustaceans (we’ve even seen them on our kayak tour searching for crabs on the prop roots of the red mangroves!). Cariblancas are opportunists, and will even eat bird eggs, nestlings and small mammals, which all together allow for the capuchins tend to be a very active species. If you come across a troop, you’ll also notice how curious they are, staring down at your with furrowed brows, fairly reminiscent of an tiny, angry old man. They have even been known to throw seeds and even limbs at our guests!
Capuchins range quite high in intelligence among the New World monkeys, as demonstrated by their use of tools. They’ve been known to rub millipedes, which emit cyanide as a defense mechanism, onto their fur, perhaps using it as an insect repellent. They’ve been documented using hard surfaces to break open mollusks and sticks to explore cavities for food.
The Geoffroy’s Spider Monkeys that live in our forest were in decline likely due to overhunting in the past. We’ve been thrilled to witness the species in this area more and more lately because, as we learned from a biologist Jenna Griffiths, who is doing her PhD on spider monkeys, this species has been absent from this area of Piedras Blancas National Park in the past. She is very interest in and excited about these sightings. One of our guests was even fortunate enough to see the mega-troop, of some fifty individuals. These troops break up into smaller groups during the day to spread out and forage for food. We’ve started to see and hear them more and more this season, often up the stream valley up the hill.
Spider monkeys are aptly named for their elongated appendages. They actively swing through the high branches and forage mainly on fruit but will add young leaves and seeds to their diet to obtain sufficient protein. Watching these monkeys swing their way from one branch to another is always a delight, especially knowing you’re observing an endangered species who’s populations have suffered from deforestation and hunting. While we’re enamored with these charismatic creatures, they definitely have a flare for letting their own opinion of humans known, like when one of us is staring up at it from below, these monkey won’t hesitate to grab a branch with every appendage (including that long tail) and shake everything in their reach with gusto, as if to let you know who’s boss. If I were an endangered animal looking down at the species responsible, I’d likely do the same!
Our last animal in the picture collage is the beloved Three-toed Sloth. They’ve been a rare sight this season so every sighting has been enormously special. We’ve seen them now three times in the big cecropia tree at the edge of the garden. Sloths seem to have a preference for these trees, and since the leaves of the cecropia have a mild narcotic, that might explain not just their common presence in these trees in general, but likely adds to their very slothfulness! To learn more about the amazing natural ecosystem sloths harbor in their pelt, check out my blogpost up on Saladero’s website describing this fascinating, arboreal and simply adorable creature!
Some other interesting arboreal mammals harbored in the treetops of the forest include the Margay, a small spotted wild cat that has a tail nearly as long as it’s body which aids in balance as it walks along the branches above. The margay prefers life in the trees, hunting birds and even monkeys. It has the unique ability to twist its ankles to aid in its head-first descent to the forest floor as it moves to different hunting grounds. This forest cat is highly agile and is able to jump up to four meters horizontally and 2.5 meters vertically. While I have yet to see a wild cat in the forest here at Saladero, they’re definitely here along with a variety of other wild cats, as our motion-detecting camera traps convey!
Another arboreal creature of the treetops is the Kinkajou. This unique-looking creature is in fact related to raccoons. Similar to the margay, the kinkajou also has the ability to turn it’s feet widely in either direction to aid in its movement through the trees. The kinkajou’s tail is prehensile and used just as often as its other appendages as it travels from branch to branch. It will even use it as a furry pillow to curl up with to sleep. These fascinating mammals also go by the moniker “honey bear” for their inclination to raid beehives for their honey. We have some honey bears here at Saladero that like to make their presence known by dropping seeds onto the roof of our Treehouse cabin. But with that adorable face and huge, liquid black eyes, who could chastise them?