Those Spooky Sounds in the Trees? Say Hello to Costa Rica’s Mantled Howler Monkeys

Happy Howl-O’ween! 

You can bet that this Halloween night in the Osa Peninsula will be full of the thunderous calls of the Mantled Howler Monkey. 

It’s a sound that delights our clients, those who love to be surrounded by nature and all kinds of wildlife. In fact, guests at Villa Maravilla this year described the call of the howler monkey and wildlife visits as quite the experience! 

“The grounds afford a daily show, including a variety of wildlife, ranging from toucans and iguanas to howler monkeys.”

While over at The Jade House, our friends let us know that they found the villa “magical” and were excited to report that they “heard howler monkeys every morning, found the sloth every day, got to watch white-faced monkeys jump from tree to tree.”

But this wasn’t always the case. In fact, long ago when explorers wrote home about what they heard in the night, they described the howler monkey’s roar to be a frightening scream that would scare any man. It makes sense to be a bit weary of an animal whose roaring howl can travel 3 miles. And, according to the International Fund for Animal Welfare, the howler monkey’s call can reach up to 90 decibels.

Mono Congos in Costa Rica Wear Cloaks!

The Spanish term for howler monkey is “mono congo.” The scientific term is “Alouatta palliata.” A Palliata was a cloak or mantle worn by ancient Greeks. The howlers have dark black fur, accented by a fringe of longer, lighter colored hairs running down both sides of its body and back. This literally gives the appearance of wearing a cloak. 

What better animal to feature on Halloween! This monkey can hang out among the rest of the cloaked characters that come out at dusk… Count Dracula, the Grim Reaper, the Headless Horseman. The long list of cloaked dark creatures howling on all hollow’s eve just got longer. 

What do Howler Monkeys look like?

In addition to wearing a cloak and howling loudly through the canopy, you’ll want to keep your eyes peeled for a “stoutly built bearded monkey with a hunched appearance and thickly furred prehensile tail.”

We admit that description does sound a bit scary, particularly the hunched and cloaked bit, but look how cute this baby howler is.

Howler monkeys usually weigh-in around 15 to 20 pounds. That thick prehensile tail is basically a fifth limb. It allows them to hold on while sleeping in the canopy and traversing branches and gaps in tree cover. The tail can support their entire body weight, but they tend to use their feet as well. 

They are slow movers and spend most of their time high up in the branches. Therefore, be sure to look up when around these parts. You’ll almost never spot them on the jungle floor; they stick to the canopies. Up there they can dine on leaves and fruit all day, in between a number of siestas and a long night’s slumber. 

In fact, they rest or sleep the entire night. Then they rest again for a good 75 percent of the day. Since the mono congo relies mainly on low energy food, they tend to conserve their energy. It’s a lot easier to howl across the river to a neighboring troop than to swing through the branches and possibly get into a scuffle. No, these animals are all about the pura vida lifestyle and are not overly aggressive. Like a tired grandparent, they’d much rather spend the day resting.

One reason they might tend not to fight within the group is due to the fact that the members of the group are not related to each other. Troops can number from four to 20 monkeys. Both males and females leave their parents’ troop and find a new one before reaching maturity. Hence, parents never have to deal with those angsty teenage years.

How to spot Howler Monkeys in Costa Rica

The best way to spot a howler monkey in Costa Rica is to listen for the sound of their deep roar. Howler monkeys get their name for the howling calls they make. Dawn and dusk are the prime times to hear the call. The booming roar is so loud it can be heard miles away. 

The howl isn’t the only sound they make. They can also belt out some grunts, some woofing barks and even an eery shriek and cackle. All excellent sounds to fill any Halloween eve! In fact, this array of sounds is likely why Fodor’s travel guide says those early explorers compared them to “demons crying out in the trees!” 

Where can I see Howler Monkeys in Dominical, Uvita and Ojochal?

Along the beautiful coastline of Costa Rica there are lots of ways to have a howling good time. Luxurious vacation homes, incredible restaurants, amazing adventure tours and, of course, epic wildlife viewing. 

As we mentioned previously, guests at Villa Maravilla, The Jade House and Villa Dalu (just to name a few) have all spotted or heard the great Mantled Howler Monkey. Casa Pura Vida is a known hotspot for monkey troops traveling through, as is Casa San Martin Mirador.

A study on the species Aloutta Palliata’s travel habits showed that groups love to reuse past travel routes. They enjoy returning to known feeding spots and their favorite trees to rest in. So, if they’ve been spotted at the villa previously, they’ll likely return. They are intelligent enough to remember specific landmarks, and use them to find routes back to their old hangouts.

The odds are good that you’ll hear or see the mono congo near your villa or Hacienda Baru in Dominical. Lonely Planet has also found that the howler monkey is one of the most commonly seen and heard primates in the national parks of Manuel Antonio and Corcovado. If you’ve booked an amazing adventure tour to either of these places, your odds just got even better.

Do Howler Monkeys Howl Before Rain?

Rumor has it that howler monkeys will sound off just before rainfall arrives. Are they, in fact, nature’s own meteorologists, announcing the coming showers a la Al Roker back in the day?

Ponder that question as you prepare to trick or treat this year. Also, when the darkness arrives on October 31 and thunderous sounds begin to rain down from the skies above, don’t worry it’s probably just the howler monkeys letting you know it’s about to pour. 

Either that or a Stephen King novel is coming to life in real time and you should absolutely seek shelter. One way or another, try to embrace the experience. Happy Howl-O’ween, folks!