The Howl of Howler Monkeys in Panama Explained

Howling Howler Monkey

Did you ever hear your parents say, "I need a break...I need some PnQ, and RnR!"? Coming from a family of 7, I am sure mine said that a LOT or, at least they surely dreamt of it. I wonder what that looked like for them and how about for you? When you envision your peaceful place a.k.a. your happy place what does that look like? I'm guessing for a lot of people it might look a little something like:

A guest in her happy place while on our snorkeling tour

We like to describe our 5+ acre (2+ hectares) lush jungle enclave as a peaceful pocket of tropical paradise on an idyllic and secluded surf beach. When we walk our guests through their arrival orientation, we talk a lot about the howler monkeys and how to peacefully enjoy coexisting with them which is truly never something one ever takes for granted. What we don't talk about is their early morning wakeup call which makes for some fun coffee talk the next day and maybe a few disgruntled sleepy teenagers. But somehow, it's still the peaceful place we describe because their sound is so natural.

In the early morning hours, tucked in and snoozing snug as a bug in a rug, dreaming about coffee, a terrifyingly loud and powerful roar suddenly erupts from the jungle outside your private terrace doors that makes you cling to your pillow in fear and wonder if you should be terrified and run or go to the doors in search of the source of a sound even Freddy Krueger couldn't unleash.

Azuero Mantle-Backed Howler Monkeys Howling

I hope in your mind you went out on the terrace to take in the intensity of the moment in nature. Let's just say that's what you did so, you're sitting there, in pure darkness, on your hammock, in and out of morning sleep between the howls wondering what it is because it's too dark to see the monkeys and by the time the sun comes up to illuminate the source, nothing is there! Thankfully, the coffee is just a short walk away and we await your bewilderment of natures wakeup call.

Proof that size has nothing to do with volume; it's hard to imagine such a powerful sound coming from such a small animal! Let's have some fun with numbers: To give you an idea, one of the loudest cities in the world in NYC, which measures at 85 decibels (dB), a lion is 114 dB, you think your partner is a loud snorer? They are likely at about 65 dB. Now, a cicada is at a hot 106 dB, and a howler monkey...wait for it...140 dB!!! That's right, the loudest land animal on the planet. A heck of a lot louder than a lion which kids love to hear.

So, how do they do it you're wondering? The secret to the howler monkeys’ loud calls lies in their unique anatomy. Unlike most primates, howler monkeys have an enlarged hyoid bone, a structure in the throat that supports the vocal cords. This bone acts like a resonating chamber, amplifying the sound of their calls.

The hyoid bone is hollow and shaped like a cup, which allows it to vibrate and increase the volume of the howls. When a howler monkey calls, air passes through the vocal cords and into this bony chamber, producing a deep, booming sound.

RIGHT: Skeleton of a male Alouatta in which the hyoid bone is clearly visible –throat region. LEFT: two images of the hyoid bone showing its chamber-like structure (top) and smooth surface and elongated shape (bottom). The hyoid is very robust (made mostly of compact bone tissue). From Evolution Literacy

Additionally, howler monkeys have strong neck muscles as you can see in the video that help push air forcefully through their vocal cords. This combination of physical features allows them to produce sounds that can be heard over long distances, as far as 4 miles even in noisy forest environments.

We all know why you're sister was yelling at you (stealing her clothes) but why do the monkeys howl? Such wonderment and entertainment we get from nature - I'd say even better than Taylor. Thanks nature! Seriously though, typically it's the dominant male that howls the loudest and for a variety of reasons.

Monkeys are a highly social animal living in troops as large as 30 at a time with everyone having their defined roles like humans do and also like us, they like to kick the kids outta the house to start their own families - male and female alike. This helps them to seek out a mate and create a new family and even more importantly - avoid interbreeding.

That's getting to be harder and harder actually, near to impossible as mass deforestation causes fragmented forest systems everywhere here in Panama. So that interbreeding is occurring and with only 1,000 of the Azuero Mantle-Backed Howler monkeys left they don't have the long term genetic sustainability needed to avoid extinction.

What's that have to do with their howl? I'm glad you asked: Their digestive system is working extry hard to digest the leaves that make up the majority of their diet so to communicate with their families from afar, their howl helps them to save the need to travel the canopy to let them know where they are, what food is available in the area, where they might be laying claim to territory, presence of predators, and perhaps the excitement of a newborn in the troop.

Speaking of beautiful forests to eat great food, consider this our written howl to you to COME STAY WITH US IN PANAMA! Did you hear it? Especially if you are looking for an awesome place to celebrate an upcoming graduation this Spring. Anyone in your family interested in learning about monkeys and nature? From the forest to our Mellikki's Primate Rescue Center, we are here to teach and share with anyone and every one of our guests about these beautiful animals and inspire the next generation why conservation of these species is so important.

With love from Panama,

Cari and Ryan Mackey

Owners and hosts