WOOLLY MONKEY FACTS
| Family: Cebidae |
Subfamily: Atelinae |
| Genus: Lagothrix |
Species: 2 |
|
There are 4 subspecies identified within lagotricha. Some of these may be separate species.
Appearance:
Their name comes from their dense, soft, short fur. Woolly monkeys' fur varies in color - can be brown, grey, or black. The yellow tails are a deep mahogany with, obviously, yellow on the underside of their tails and on a tuft of hair at their scrotums. They have round heads and bellies, snub noses, and powerful prehensile tails. Their limbs are almost of equal length, with an intermembral index of around 98. Females, like their relatives, the spider monkeys, have elongated clitorises. The yellow tails' faces have a yellow triangular patch over their mouths and noses. Infants are a lighter color than adults. This species does not display sexual dimorphism - the range of lengths and weights is similar for both genders. Female weight average is around 11 lbs., while males are around 15 lbs.
Range and Diet:
Woolly monkeys are found in the Amazon Basin in Brazil, Colombia, Ecuador, and Venezuela. The yellow tails are only found in a small part of western Peru. They range in all canopy levels of primary rainforest, and have been found in mountainous areas up to 3000 meters.
They feed predominantly on fruit, but also eat leaves, seeds, gums, flowers, eggs, and animal prey, which can include small mammals.
Behavior and Social Structure:
Group size for woolly monkeys averages 10-12 members, though much larger groups, with as many as 70 individuals, have been seen. Subgroups will form and move independently of the larger group. They are not very territorial - group ranges overlap and they have even been known to forage alongside other species of cebids. Group composition is multimale-multifemale. Males have an age-graded dominance hierarchy. In captive studies, males were observed to form coalitions. Grooming does not seem to have the importance it has with other monkey groups.
These monkeys are almost totally arboreal, moving with all "five" limbs. They do not travel as fast as spider monkeys and rarely leap. When they do come to the ground they tend to move about bipedally.
Woolly monkeys have exhibited 14 distinct vocalizations, including a "sobbing" vocalization associated with submissive behavior and a group alarm call. Males show aggression by rubbing their chests and shaking branches.
Reproduction and Lifespan:
Average age for their first birth is 60 months. Gestation period is around 223 days. Females will lip smack when in estrus and will mate with more than one male. Woolly monkeys live about 26 years.
Conservation Status:
Vulnerable (IUCN.) The yellow-tailed woolly is listed as Endangered by USESA. Hunted for the pet trade, and for food, fur, and medicine. First to disappear when the habitat is disturbed.
Interesting Facts:
There is still a lot we do not know about their behavior and breeding seasons.
Up until 1974 the yellow-tailed woolly was thought to be extinct.
Woolly monkeys have been used in psychological studies and found to display stage 4 and 5 object permanence - searching for and tracking hidden objects.
Current Research with Woolly Monkeys:
(Note: The following are examples of recent research done with these primates, it is by no means an exhaustive list. This list will be periodically updated as more information becomes available. Also, though Mindy's Memory Primate Sanctuary DOES NOT support invasive medical research on primates, some articles of this type will be listed - both for information and as examples of the work that is currently being done with these animals.)
Kinzey, W G
Synopsis of New World primates: Lagothrix. Pp. 264-271 in NEW WORLD PRIMATES: ECOLOGY, EVOLUTION, AND BEHAVIOR. W.G. Kinzey, ed. New York, Aldine de Gruyter, 1997.
Stevenson, P Vocal behavior of woolly monkeys (Lagothrix lagotricha) at Tinigua National Park, Colombia. FIELD STUDIES OF FAUNA AND FLORA, LA MACARENA, COLOMBIA 10: 17-28, 1997.
Stevenson PR
Proximal spacing between individuals in a group of woolly monkeys (Lagothrix lagotricha) in Tinigua National Park, Colombia. INTERNATIONAL JOURNAL OF PRIMATOLOGY 19(2): 299-311, 1998.
Taylor SR
1998 NORTH AMERICAN REGIONAL WOOLLY MONKEY LAGOTHRIX LAGOTRICHA STUDBOOK. Louisville, Louisville Zool Garden, 1998, 54 pp. (Data through 4/30/98)
Woolly Monkey Websites
References:
Rowe N (1996) The Pictorial Guide to the Living Primates. East Hampton: Pogonias Press
Sleeper B (1997) Primates. San Francisco: Chronicle Books
Tomasello M and Call J (1997) Primate Cognition. New York: Oxford University Press
