What Is a Howler Monkey?

Taxonomy

• Howler monkeys belong to the taxonomic order of primates, which includes all other monkeys, apes, lemurs and humans. Within this they belong to the family Atelidae, a group of New World monkeys, and most specifically, the genus Alouatta.

Species

• The term howler monkey often refers just to Aloutta caraya, the black howler monkey. This animal, along with its close relatives, is probably the loudest land animal in the world. The 14 other species include a couple of highly endangered species: the Yucatan howler monkey (A. pigra) and the Maranhão red-handed howler monkey (A. ululata).

Distribution and Habitat

• Howler monkeys are found only in South and Central America. They inhabit rainforest, dry forest and cloud forest habitats. Some species live in the bush savannah of Brazil, a mixed habitat of forest, scrub and water bodies that experiences both wet and dry periods. Because of the dry periods, the bush savannah is both prone to, and reliant upon, forest fires, which lead to regrowth. Like other large animals of the area, howler monkeys adapt to periodic fires by moving away and then returning.

Calls

• The most obvious characteristic of howler monkeys is their very loud vocalizations. The purpose of these is for a troop to establish territories, warning off other troops. The monkeys can also communicate with and warn each other of threats in their very dense forest habitat. Body language is only useful very close up, and a troop may be spread out through a wide area.

Other Physical Characteristics

• Other distinguishing characteristics include a prehensile tail, something the Old World monkeys do not have. Howler monkeys' hair, whose color depends upon the species and sometimes the gender, is long and they often sport beards around their faces. Howler monkeys are the largest monkeys in the Americas.

Diet

• Howler monkeys consume a varied herbivorous diet. They eat primarily leaves, supplemented with fruits, but also consume flowers, roots, bark and other edible parts of plants. Unlike many monkeys, they rarely, if ever, consume animal material.