If you visit a rainforest in Central or South America at dawn, the first thing you may hear is a deep, roaring call echoing through the trees. That sound belongs to the howler monkey, often called the loudest land animal in the Americas.
Here are the most fascinating howler monkey facts, from how they produce their famous call to what they eat and how they live.
Howler Monkey Facts at a Glance
| Fact | Details |
|---|---|
| Genus | Alouatta (around 15 species) |
| Range | Southern Mexico to northern Argentina |
| Body length | About 56 to 92 cm (22 to 36 inches) |
| Weight | Roughly 4 to 10 kg (9 to 22 pounds) |
| Diet | Mostly leaves, plus fruit and flowers |
| Lifespan | About 15 to 20 years in the wild |
| Group size | Usually around 4 to 20 monkeys |
How Loud Is a Howler Monkey?
A howler monkey’s call can be heard up to about 5 km (3 miles) away in dense forest. Males have an enlarged hyoid bone in the throat that works like an echo chamber, making their roar deep and powerful.
Why do howler monkeys howl?
- To tell other groups where their territory is
- To avoid fights, since groups can judge each other’s size by sound
- To keep their own group together
- Often at dawn and dusk, and sometimes before rain
What Do Howler Monkeys Eat?
Howler monkeys are mainly folivores, meaning leaves make up a large part of their diet. Leaves are low in energy and hard to digest, so howlers spend much of the day resting. They also eat fruit, flowers and buds when available.
Where Do Howler Monkeys Live?
Howlers live in many forest types, from tall rainforests to dry forests and mangroves. Some species cope better with forest fragments than other monkeys, but they still need connected trees to move and find food.
Howler Monkey Family Life
- Groups usually include one or a few adult males, several females and their young.
- In some species, adult males and females have different fur colors. Black howler males are black, while females are blonde or tan.
- Babies cling to their mother and are carried for months.
- Like spider monkeys, howlers have strong prehensile tails.
How Long Do Howler Monkeys Live?
Wild howler monkeys typically live around 15 to 20 years, and sometimes longer in zoos.
Threats and Conservation
Some howler monkey species are doing well, while others are endangered. Habitat loss, hunting, the pet trade and diseases such as yellow fever have caused declines. Power lines are another danger in some areas, so conservation groups build canopy bridges to help monkeys cross roads safely.
Can you keep a howler monkey as a pet?
No. Howler monkeys are wild animals with a specialist leaf diet and strong social needs, and primate ownership is restricted or banned in many places.
Howler Monkeys vs Spider Monkeys
| Feature | Howler monkey | Spider monkey |
|---|---|---|
| Main diet | Leaves | Ripe fruit |
| Activity | Rests much of the day | Very active and agile |
| Famous for | Loud roaring calls | Long limbs and swinging |
| Thumbs | Present | Tiny or absent |
Tips for Seeing Howler Monkeys in the Wild
- Listen at dawn, when calls are most common.
- Look up into tall trees near rivers and forest edges.
- Use binoculars and stay quiet.
- Never feed or approach monkeys, and do not stand directly under a group.
Note: This article is general information. Primate ownership laws vary by location.
Helpful Resources
More guides from Pet Guide Nest:
Trusted outside sources:
Frequently Asked Questions
How far can you hear a howler monkey?
Their calls can carry up to about 5 km (3 miles) through the forest.
Why do howler monkeys howl?
Mainly to mark territory and space out groups, which helps them avoid fights. They often call at dawn and dusk.
What do howler monkeys eat?
Mostly leaves, plus fruit, flowers and buds.
Are howler monkeys dangerous?
They are not aggressive toward people in the wild, but like all wild animals they should be watched from a distance and never fed.
Final Thoughts
The howler monkey’s roar is one of the great sounds of the natural world. Protecting connected forests means future visitors will still wake to that call echoing through the trees.
Maren Ashcroft
Maren Ashcroft writes the care guides at Pet Guide Nest. She has grown up around dogs, cats, and rabbits and loves learning about the more unusual pets too. She turns vet and animal welfare research into simple, practical advice for everyday pet owners.
