Animal of the Month
November 2017

Name: Brown Spider Monkey (AKA Variegated Spider Monkey)

Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Atelidae
Genus: Ateles
Species: A. hybridus
Number of Species: 2
A. h. hybridus,
A. hybridus brunneus.

Size: About 20 inches long
Weight: About 17-20 lbs

Characteristics: Furry, bears a small head, long arms and legs with opposable thumbs and a long prehensile tail.
Color(s): Brown on the back, legs and arms and white on the underbelly and parts of the face. Has a triangular-shaped patch of white fur on the head and some individuals have striking blue eyes.
Behavior: Diurnal, arboreal, lives in groups, travels almost exclusively by swing-ing on tree branches.
Preferred Habitat: Tropical rainforests, particularly the canopies
Range: Northern Columbia and northwestern Venezuela
Diet: Mostly fruit but will also eat leaves, flowers, seeds, decaying wood and oc-casionally clay and soil.
Lifespan: About 27 years in the wild, perhaps 37 in captivity.


Ever wonder what your tailbone is for? Millions of years ago, the primates that humans descended from had tails and lost them as they evolved into apes and hominids. The tailbone we carry is all that is left. Many primates however still have a tail, and few use it as well as the brown spider monkey! Brown spider monkeys (also called variegated spider monkeys) are found in northern Columbia and northwestern Venezuela. They spend almost all of their lives in the canopies of tropical rainforests.

There are two species of brown spider monkey: Ateles h. hybridus, and its subspecies Ateles h. brunneus, which is found in Columbia. Brown spider monkeys live in groups that range from 2-31 individuals. They spend their days foraging in the upper levels of the rainforest searching for their favorite food: fruit. They also will eat leaves, flowers, seeds and decaying wood. The brown spider monkey's quest for food isn't just important for their own survival; they act as major seed dispersers and help certain plants to reproduce! A group will often split up into smaller groups to search for food. While separated they will call to each other with a series of whoops and wails. Later when the group reunites, the monkeys act excited and bond by hugging, vocalizing, entwining their tails and chasing one-another. It must be like a fun family reunion!

Brown spider monkeys are capable of walking, but rarely do so. Instead, they prefer to use their long arms swing from branch to branch. Their strong pre-hensile tail acts as a fifth arm to help them get around! They will only climb to the ground to drink water or occasionally to eat clay and soil. It is believed that they eat these soils as a mineral supplement. They are often hunted by jaguars, pumas and eagles. When confronted, brown spider monkeys will shake tree branches in an attempt to intimidate the predator.

Female brown spider monkeys reproduce every three or four years. They carry their young for about 225 days before they give birth to a single baby. The baby will hold on to its mother's belly for the first four months of its life, then it will ride on her back and eventually travel on its own.

Brown spider monkeys are critically endangered, to the point that they are included on the list of the 25 most threatened primates on Earth. They are mostly overhunted for food, but also face threats from habitat destruction as humans expand into their territory and convert land for agricultural use. Brown spider monkeys have a low population density and a slow reproduction rate, so their numbers are not quick to recover.

Fortunately there are many dedicated people who are fighting to preserve this unique species. Breeding programs have been established in Europe, and biologists are racing to study the distribution of these monkeys. A. h. hybridus exists in several protected areas in both Venezuela and Columbia. A park has been proposed in the Serranía de San Lucas massif in Columbia to protect A. h. brunneus as well as other primate species, but this has yet to be put into effect due to civil unrest. Conservation is difficult if not impossible in certain parts of this region as governments become unstable and violence more likely. Ironically, this civil unrest may also be delaying the destruction of the brown spider monkey's habitat! In any case, spreading awareness on the plight of these primates and the jungles they call home will help to ensure their survival.

To join the fight to save these primates and their habitat, check out these awesome organizations:

Primate Conservation, Inc. - Dedicated to protecting primates around the world.

Rainforest Trust - An organization that protects threatened rainforests by buying land and safeguarding it from those who would develop it.

Rainforest Concern - A British charity that fights to protect the biodiversity and indigenous peoples of South America.


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