5 Fun Facts You Never Knew About Howler Monkeys

If you’ve ever had the opportunity to visit a South American rainforest, you’ve probably heard the call of howler monkeys. The “howl” sounds more like a belch than the howl of a wolf, but they can be heard up to 3 miles away! Here are 5 other fun facts about howler monkey.

#1 – They’re the loudest land animals

It’s thought that the howling is a method of marking their territory. The leaves that they eat only provide minimal nutrition, so howler monkeys don’t have the energy to fight each other over territory. They have extra large throats and hyoid bones in order to produce the “howling” sounds.

#2 – They can hang from their tail

Image source: ilouque via flickr

Unlike Old World monkeys, howler monkeys have prehensile tails that can grasp objects and support their weight while dangling from a tree branch. This ability comes in handy since they hardly ever descend from the rainforest canopy.

#3 – They live in groups of 6-15 animals

Image source: _paVan_ via flickr

There are usually 1-3 males and multiple females per group. Juveniles of both sexes usually leave the group after reaching sexual maturity, which is different from most other primate species. This results in most howler monkeys spending their lives with unrelated animals.

#4 – Males and females may be different colors

Image source: _paVan_ via flickr

In some howler monkey species, males and females may be different colors and may not be recognizable as being the same species. In black howler monkeys, for example, all babies are born gold. Females remain gold and males turn black after sexual maturity.

#5 – They eat mainly leaves

Image source: Gregory “Slobirdr” Smith via flickr

They’re the only folivores (leaf-eaters) of the New World monkeys. While they eat mainly canopy leaves, they will also eat fruit, buds, flowers, and nuts. The will also occasionally raid birds’ nests and chicken coops for eggs. They need to be sure they don’t eat too many of the same type of leaves in one sitting as the leaves may contain toxic poisons.

(H/T: Wikipedia, National Geographic)