Howler Monkey

By Alexander Holmgren

Scientific Name: Alouatta
Where in the World: Tropical Central and South America
How Big: 13.3 to 15.4 lbs (6-7 kg)
What Does It Eat: Mostly leaves, as well fruit, nuts, and flowers.
How Many: Non Threatened

Howler monkeys are on the largest new world primates and are recognized as the loudest land animal in the world. They’ve earned both this reputation and this name from the unique enlarged hyoid bone in the throats of howler monkeys, that are the keys to their characteristic “howling”. These vocalizations can be heard from up to twenty miles away and act as territory protection/marking and mate protection. Another interesting fact about these unique animals is the affect they have on people, writer have often saw them as indicative of sadness and a serious composure, and the Mayans worshipped them for their beauty and had depictions of them as gods.

The howler monkey group contains 15 different species of howler monkeys, all of which are native to the forests of Central and South America. Howler monkeys live within groups of five to fifteen individuals with usually about three males and the rest all females. What’s unique about these group structures though is that both male and female juveniles will leave the group they were born in and join a new one, with the majority of their adult lives spent in groups that they aren’t related to.

Black Howler Monkey in Belize. Photo by Rhett A. Butler
One of the howler's primary senses is its keen sense of smell. These monkeys have short snout with wide O shapes nostrils; these noses are capable of smelling food such as fruits and nuts from over two kilometers away. Another interesting characteristic of howlers monkeys is their tails. The tail of howler monkeys is in most cases roughly the same size as the body and is prehensile, meaning it can fully wrap around objects such as branches. Not only that but the tails of howler monkeys have tactile pads, the same structures that humans, monkeys, and apes share on their hands and feet, meaning that it can feel with the same aptitude that its hands and feet could feel with. This all means that the tails of a howler monkey acts as a fifth limb for them that is ideal for movement through the trees.

Howler monkeys are the only folivores, meaning that they eat primarily leaves, of the New World monkeys. Part of the reason for this is because they are outcompeted for fruit by the much faster and much more aggressive spider monkeys. That is not to say however, that howler monkeys do not love eating fruit, as at any chance they get they will attempt to eat it.

Red Howler Monkey in Peru. Photo by Rhett A. Butler
One of the largest threats to the howler monkey is the deforestation of their homes to use as land for farming or to obtain wood to sell. Another large threat is their value in bush meat. Bush meat is meat obtained from wild animals and is generally applied to places such as Africa, Asia, and South and Central America. It also especially applies to primates. Howler monkeys are a large and cheap source of protein and because of their usually docile nature they make for easy prey. The last major threat to these unique primates is the threat of them being abducted and placed into zoos.


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