| Howlers are big monkeys, and the males have voices to match. Their roars can be heard 3 km away in dense jungle, and 5 km in an open space - for example, across a lake. They vocalize at dawn and then again at dusk, as they head to the trees where they will settle down for the night. Females howl, too. Their calls are higher-pitched and shorter. Howler monkeys' tails are as impressive as their voices: they are very long, naked on the underside near the tip, and so strongly prehensile that a howler can hang by its tail to feed. Mantled Howlers live in groups, often of 10-20 individuals. There are usually 2-4 males, 5-10 females, and their young. They spend their days eating - figs and fig leaves are important foods - and resting.
Head and Body: 357-437 mm; Tail: 520-670 mm
Gray, J. E., 1849. Proceedings of the Zoological Society of London, 1848:138 .
Mammal Species of the World (opens in a new window).
Alouatta palliata (Mantled Howler), Panama
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