Black Howler Fact File
Wild 20 years
Captive 20 years
Black howler monkeys are named for the coloration of the males who have black fur compared to the females who have an olive-buff fur color. They are among the few primates which are sexually dimorphic.
They are a species of new world monkey and can be found in South America.
These primates mainly feed on leaves. Unfortunately this diet provides very little energy and as such they spend much of their time resting to allow time for digestion.
Unfortunately they are threatened by habitat loss, hunting for food and collection for use in medical research.
Read on to learn more about these marvellous mammals.
The black howler is named for the color of the male which is black across much of its body. Females are colored an olive-buff color across their body. This is a trait known as sexual dimorphism.
At the end of the body is a long, prehensile tail which can be used in a similar fashion to a hand when climbing through the trees. This measures 61-66cm (24-26in) long.
The hyoid and larynx are both enlarged and allow for their large howling sound.
Both male and female black howler monkeys have a black face which is hairless. The eyes are colored brown and medium sized.
An average black howler monkey will measure 65cm(25.5in) long with a weight of 4-10kg (8.75-22lbs). Males tend to be slightly larger than females.
Black howler monkeys are herbivores. Much of their diet is leaves which provide little nutrition. As such they must eat lots of individual leaves and then spend much of the day resting to digest the food. To maximize the nutrition they can draw from their food they will eat the youngest leaves.
These primates will also feed on fruits, flowers and buds.
They have been recorded near human habitations where they will feed from orchards. These populations have also been recorded to feed on bird eggs.
Much of their water is acquired from plants they eat. When the environment is dry they may need to descend to the ground to drink water from a lake.
South and Central America is the native home of the black howler monkey. Argentina; Bolivia; Brazil and Paraguay. They may potentially live in the northwest of Uruguay but this is yet to be confirmed.
The black howler monkey is found in deciduous, evergreen and gallery forest along with forest patches within savanna habitats.
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To find a mate the black and gold howler monkey will flick its tongue out. Males and females may mate with multiple partners during their life.
Females give birth to between one and two young after a 180-194 day gestation period. Juveniles are all the golden tan color of the females. Male infants will transition to black around 2.5 years old.
The parenting duties are shared between the females in the group who will work together to share carrying and protecting the infants.
A female will provide care to her infant for 12 months. Females remain in the birth group for life while the females will leave their group at sexual maturity.
Females tend to produce young every second year.
Black howler monkey's will form a group made up of multiple males and females. There are typically more females than males. Typically troops include 5 to 8 members but some have been recorded with as many as 22.
Males focus on the protection of the group and will fend off other howler monkeys which attempt to enter their territory. This allows the females to save their energy for reproduction.
Due to the low amounts of energy provided by their food they work hard to avoid wasting it on fights. This is part of the reason they howl as it allows them to prevent encountering other troops.
Groups will socialize by playing with one another and grooming.
The largest male within the group is considered dominant.
These animals are named for the loud, howling call which they make each morning to warn neighboring troops against entering their territory. Calling sessions may last for up to an hour. These calls are the loudest made by any land animal. They may be heard as much as 4.8km (3 miles) away.
Much of a black howler monkey's day is spent lying in the tree canopy while they digest their food. These animals are primarily arboreal and rarely come to the ground.
These animals mark out a territory using dung or their scent. This helps them to claim their area. They are able to recognize the scents of other monkeys.
Predators and Threats
Natural predators of the black howler monkey include large birds of prey.
Black howler monkeys face a range of threats in the wild including habitat loss to allow for agricultural development or cattle ranching. At current rates 40% of their suitable habitat would be lost by 2050.
These animals are hunted for food. Their populations have also been reduced through outbreaks of disease such as sylvatic yellow fever. Some are captured and used in medical research.
The population of the black howler monkey is decreasing.
Black howler monkeys are the loudest animal to live on land. It can reach up to 140 decibels, just less than a jet engine at around 150 decibels.
Bernard DUPONT from FRANCE, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons
Middle One and Two
Ryan E. Poplin, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons
Steve from washington, dc, usa, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons
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