by Jacqueline Trovato

Created on: July 08, 2009

Howler Monkeys are the largest monkeys in tropical Central and South America. They are named for their howling cries. The Howler is the loudest of all monkeys as well as the loudest of all land animals. The only animal that is louder is the Blue Whale. It is said that the call of a Howler Monkey can be heard for 3-4 miles even through the thick tropical forest. These social primates live high in the trees of rainforests.

Howlers live in small groups of about 12 monkeys. A Howler Monkey grows to be about 2 feet in length, not including its 30-inch tail, making it the largest monkey found in the Americas. Howlers weigh about 15 pounds when they reach adulthood. Howlers live for about 20 years.

Howler Monkeys have beards and long, thick hair which may be black, brown, or red. Male Howler Monkeys are black in color, while the females are brown. The brownish color allows the females to camouflage themselves from predators. The young howler monkeys cling to their mother's stomach for the first few months of their lives and are vulnerable to predators like the harpy eagle. Male Howlers have large throats and specialized, shell-like vocal chambers that produce their distinctive call. Scientists believe that the dominant male of the group uses his loud voice to keep the group spaced out enough so they don't have to compete for food.

Howler Monkeys spend their entire lives in the tree tops. Howlers are also diurnal, meaning they're active during the daytime. However, they spend most of their time in the canopy of the lowland rainforests. They eat mostly leaves, fruit and flowers, and prefer to stay aloft, munching on the leaves of trees. They occasionally supplement their diet with maggots.

Howler Monkeys are inactive, covering only 400 meters in a day and sleeping 15 hours a day. This makes them one of the slowest mammals in the tropical forest, except for sloths. Compared to other monkeys, Howler Monkeys don't travel very much. They prefer to stay within their small communities. This also makes them very susceptible to habitat destruction.

Howlers are in decline due to a loss of habitat. The red howler species is the most common, but it is often targeted by hunters for meat. They are now only hunted for food by local tribes but also exported as pets (although they make terrible pets, because they are social animals and very loud). They are easily located because of their loud calls, but difficult to see from the ground. Large birds like the harpy eagle also prey upon the Howler Monkey. Some scientists estimate the they could become extinct in our lifetime.

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