These monkeys are called howlers for a good reason – their calls can been heard from up to a few miles away!
Howler monkeys are considered one of the loudest land animals, with their vocalizations heard up to a few miles away, even in dense forest.
They have enlarged basihyal or hyoid bone which helps them make their loud vocalization like, howls, barks and grunts. (which have been said to sound like wind blowing through a tunnel)
In the wild they tend to make the most noise at dusk or early in the morning, howling in groups.
They are one of the largest primates in Central and South America, with a strong, stocky build and long tails which can grow almost to the same length as their bodies.
Their tails can cling on to tree branches and are used to help them climb around rainforests, though they also often walk on all fours.
Despite their reputation for howling, they spend long periods of time sitting quietly, eating or digesting food. Their diet mainly consists of greenery and small amounts of fruits.
They have large molar teeth, perfect for shredding and chewing leaves.
There are several different types of Howler Monkey, including the Mantled Howler Monkey which is all black, apart from a fringe of long golden coloured hairs on its flanks.
The Black Howler Monkey is so called because the male is all black, though the smaller females are more brownish / blonde coloured.
Howler Monkeys are very important to the continuation of rainforests as they disperse seeds in their dung so it is vital we monitor their numbers and ensure their survival.
Chester Zoo is also a strong supporter of conservation projects in the South American rainforests and every time you visit us you play an important contribution in helping us continue that support.