“What is that horrible noise that woke me up this morning?”
Howler monkeys!
People always say they want to see and be near wildlife, but it may not be what they think it’s going to be.
Sloths — everyone loves to see sloths. Mostly what they see is… a big, hairy lump on the side of a tree. If they are lucky enough to find one, that is.
Howler monkeys are pretty easy to see just about everywhere you go. But their morning “greetings” may make you wish they were not quite so close.
Howler monkeys — formally known as “Mantled Howler Monkey” to distinguish them from other howler monkeys, are also known as “Aloalla Palliata” by scientists and as “Congos” by Costa Ricans. They live in forests where most of their diet is leaves of trees. Apparently, they prefer the young leaves of certain trees — the ficus trees being one of their favorites.
They also eat some fruits and flowers. A Costa Rican friend decided to plant some corn in the back of the property to try and attract the neighborhood howlers. They loved it! The problem is… now he can’t plant any corn to eat because they always get to it first!
You can find the howler monkeys just about anywhere there is forest: From Tortuguero to Cabo Blanco and from Rincon de la Vieja to Corcovado.
That “horrible noise” you hear at dawn (or sometimes earlier) is the call that they make to other groups of howlers. They have a special configuration in their throat to allow them to make that loud roar that can be heard several kilometers away. They also make other types of noises to communicate, such as clicks and grunts and a kind of squeal.
Because the main part of their diet is leaves which are not high in calories, they communicate over long distances rather than moving to be closer to other groups which takes a lot of energy.
The mortality rate for young howlers is high and only about 30% live more than one year. For their predators — big cats, weasels, snakes and eagles — those young monkeys are delectable morsels! Very young howlers also can die from falling out of a tall tree when misjudging a jump. Once they survive that first year, they will typically live around 25 years more.
Because they spend 100% of their time in the trees, they need to find sources of water, other than the water they get from the leaves they eat. For this, they drink the water that is caught in tree bromeliads and from any holes in the trees that can collect water.
It’s usually easy to see (or hear!) howlers at Casitas Tenorio. Some tips for finding them….
What to look for:
- Watch the trees! Look up or out and around you. There’s no need to depend on someone else to point them out to you. Look for branches that move when there is no wind. This is a good sign that there are howlers moving through.
- Listen for their calls, both the “roars” and the other calls. Some of the calls are just the “huh huh huh” that we associate with monkeys. Then start looking around.
- Look for the trees that have leaves they like to eat – mainly ficus or fig trees. You can Google “Costa Rican ficus trees” for some photos and you will know what to look for. They do eat the leaves from a variety of trees, but these are their favorites.
- Spend some time watching them. It’s not just for checking a box saying “I’ve seen a howler monkey!” but it’s a time for watching how they act, how they interact, how the little ones manage.
- Have your camera ready!
