Alouatta pigra
Meet Belize's Black Howler Monkey
Yucatán Black Howler Monkey Classification
Class: Mammalia
Order: Primates
Family: Atelidae
Genus and Species: Alouatta pigra
Howler Monkey Fun Facts
- Howler monkeys are the loudest land animal on earth and can howl at a volume of 140 decibels
- Unlike other monkey species where fathers take a role in parenting, female Yucatán black howler monkeys are single mothers and will spend an entire year completely dedicated to raising their baby.
- The howler monkey population in Belize increased from 450 to 4500 individuals since the Community Baboon Sanctuary's inception
- The Yucatán black howler monkey is one of two species of monkey found in Belize. The other is the Geoffroy's spider monkey.
The Yucatán black howler monkey is classified as endangered by the IUCN Red List.
Male Yucatán black howler monkeys are about 11.4 kg (25 lbs) on average while females are normally around 6.4 kg (14 lbs)
Including the tail, the monkeys generally range in length from 43 to 52 inches long.
Yucatán black howler monkey can live up to 20 years in the wild.
The Yucatán black howler monkey is found in evergreen forests, semideciduous forests, and lowland rainforests throughout Belize, Guatemala, and the Yucatán region of Mexico.
The black howler monkeys are herbivores who eat mostly fruits and leaves. Mangos are a particular favorite food of howler monkeys living in Belize.
About the Yucatán Black Howler Monkey
Why are they called Baboons?
You might be a bit confused about why our organization is called the “Community Baboon Sanctuary” if we have been talking about Howler Monkeys this entire time. However, there is quite a good reason behind our sanctuary’s name!
“Baboon” is the Kriol (creole) word for the black howler monkeys found in Belize. When our African ancestors were originally brought to Belize by the British, we had never seen monkeys exactly like the howler monkeys before. Baboons, however, were common back in Africa. When our ancestors saw these new monkeys in Belize, they figured “It must be some sort of baboon.” And thus, the name stuck, and “baboon” became the Kriol word for the black howler monkey.
Features of the Black Howler Monkey
Yucatán black howler monkeys are the largest monkeys in Latin America and the largest among howler monkeys. Both males and females have beards, with males having noticeably longer ones. Infants are born brown and their coats turn black as they grow.
Their large throats house an enlarged hyoid bone, which produces their deep, booming calls. Males’ hyoid bones are up to five times larger than females’, enabling their calls to be heard up to 3 miles (4.8 km) away at 140 decibels, making them the loudest land animals.
Behaviors
Belize’s black howler monkeys are active during the day and live in trees. They move on all fours across branches, always holding on with at least two limbs or a limb and their tail, which is strong enough to support their body weight. Compared to other monkeys, the black howler monkeys are typically slow movers and tend to stay in the upper branches. When traveling, the monkeys move in groups led by an older male. Black howler monkey group sizes vary, typically averaging six members, and can include single-male or multi-male groups. Troops are stable, feeding, sleeping, and traveling together, though they may temporarily split up to forage. They get most of their water from the plants they eat.
The monkeys’ howls, often heard at sunrise and sunset, serve to establish territory and communicate within the group. These howls can last up to an hour in the morning and evening but are shorter during the day. Environmental factors like sunlight and rain can influence the duration of their calls.
Yucatán black howlers are polygynous, with males mating with multiple females. They breed year-round, usually having one baby annually. After a six-month pregnancy, the mother gives birth to a single infant, which she carries and nurses. At about three weeks, the infant starts eating leaves and rides on the mother’s back. The fathers do not participate in childrearing and the mother monkey will dedicate an entire year to focus on raising her baby.
Conservation Issues
The Yucatán black howler monkey is listed as Endangered by the IUCN. The population is projected to decline by 50% over the next three generations due to deforestation, with an estimated 31% of their habitat disappearing by 2048.
Deforestation is driven by urban development, agriculture, and logging. Forests are cleared for housing, farming, and cattle ranches. Natural disasters like hurricanes and climate change-induced storms also destroy habitats.
Hunting, especially in Mexico, and the illegal pet trade also contribute to their decline. In Belize, owning a monkey is illegal.