Lagothrix lagotrichaHumboldt's woolly monkey

Geographic Range

Common woolly monkeys (Lagothrix lagotricha) occur in the Neotropics of northern South America, including the upper Magdalean River valley in Colombia, throughout much of the upper Amazon basin of Colombia, Ecuador, Peru, Bolivia, Brazil west of the Rio Negro, and in the foothills and eastern slopes of the Andes. They occur as high as 3000 meters above sea level in the Andes (Eisenberg 1989; Emmons & Feer 1990; Moynihan 1976).


Common woolly monkeys are hardly ever found on the forest floor. Generally, they remain at a height of about 38 ft (12 m) but will come down as low as 22 ft (7m). Lagothrix lagotricha live in gallery, palm, flooded and nonflooded primary, and cloud forests. These animals prefer mature, continuous, undisturbed humid forests and are not found to inhabit secondary forest. (Kinzey, 1997; Nowak, 1999; Welker and Schafer-Witt, 1989)

  • Range elevation
    0 to 3000 m
    0.00 to 9842.52 ft

Physical Description

Common wooly monkeys are large robust animals and are one of the largest New World primates by weight. Males are generally heavier than females, and male canine teeth are significantly larger than those of females. When in captivity these animals can be much heavier in weight than 10 kg but usually individuals fall within the range of 3 to 10 kg. Head and body length ranges from 558 to 686 mm and the prehensile tail is between 600 to 720 mm. The hair is dense, short, thick, and predominantly composed of underfur. In older individuals there is a fringe of longer hair on the rear of the arms and legs and on the under belly. Color varies greatly with the upperparts being dark brown, pale smoky brown, dark gray, pale gray, red-brown, or olivaceous. In some common woolly monkeys the color of the head and limbs is distinctly darker than that of the back, in others the color is uniform. Usually the underparts are slightly lighter than the rest of the body. Common woolly monkeys have round and massive heads with naked black faces. Color varies between individuals as well as geographically. In Ecuador and Colombia, animals of different colors can be found in the same troop. Gray and almost black animals are found along the base of the Andes in Colombia, whereas olivaceous animals with dark heads are found south of the Amazon in Brazil and Bolivia. In Peru and north of the Amazon in Brazil, the brown color predominates. Newborns are straw-colored. The ears are inconspicuous and the tail is strong and prehensile. The tail is thick and muscular at the base, and tapers to the thinner tip. The limbs and body are muscular and the monkeys have a protruding potbelly. The thumbs and toes are well developed and the fingers are short and thick with long pointed nails. (Eisenberg, 1989; Emmons and Feer, 1990; Kinzey, 1997; Moynihan, 1976; Nowak, 1999)

  • Range mass
    3 to 10 kg
    6.61 to 22.03 lb
  • Range length
    558 to 686 mm
    21.97 to 27.01 in


Common woolly monkeys have an estrous cycle of about 12-49 days, in which estrus lasts 3-4 days. Full sexual maturity is reached at 6-8 years by females and more than 5 years by males. Copulation takes place over 6-11 days and starts when a female indicates her readiness to the male. The gestation period is about 225 days (7.5 months), and the normal litter size is one. Young are typically born in the late dry to mid-wet season. Weight of the newborn is about 140 grams and lactation continues for 9-12 months. After birth of the first young females will normally give birth every other year thereafter (Eisenberg 1989; Emmons and Feer 1990; Kinzey 1997: Moynihan 1976; Nowak 1999).

  • Breeding interval
    These monkeys give birth once every two years.
  • Average number of offspring
  • Average number of offspring
  • Average gestation period
    225 days
  • Average gestation period
    223 days
  • Average time to independence
    5 months
  • Range age at sexual or reproductive maturity (female)
    6 to 8 years
  • Average age at sexual or reproductive maturity (male)
    5 years
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    1520 days

The young born within a group are carried for the first month on the abdomen of the mother, and climb to the mother's back more frequently six weeks after birth. Young common woolly monkeys first leave their mothers after eight weeks, and become more independent after their fifth month.

  • Parental Investment
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • protecting
      • female



Lagothrix lagotricha individuals exhibit a broad range of behaviors in the wild. They are diurnal and arboreal but often come to the ground. They live in social groups ranging from 10 to 70 individuals. Many adult males live in a group. Larger groups are a collection of family units that may feed and travel together or travel separately, only coming together to sleep at night. Males threaten other males by shaking branches, defecating, and by barking loudly. Common wooly monkeys often groom each other, adult males receive the most grooming. Adult females are usually groomed by their juvenile daughters. Juveniles in a group play with each other around midday and they seem to have their own games. Communication can take place by vocalization, facial expression, or other visual behaviors. Common woolly monkeys can show subtle changes in mood and intention by employing a variety of facial expressions. Their calls are often loud, and can be like barks or screams. These calls are often musical and can serve to alarm the rest of the troop. In their natural habitat, and in captivity, common woolly monkeys have been observed to rub their chest. It has been mostly observed in dominant males when moving into a new territory. After sniffing the ground and licking the new location, the chest is pressed against the ground at the level of the nipples. This behavior is performed several times and the nose is applied to the marked spot each time. Chest rubbing may be a sort of marking behavior displayed by the animal when encountering new territory. Home range varies from 4 square km to about 11 sq. km and some individuals can travel about 1 km a day. Group ranges may sometimes overlap and individuals (especially subadult females) may temporarily leave their own group and spend a few hours or days with a different one. On the ground, common woolly monkeys will walk upright on their hind legs, using their arms to maintain balance, but they are primarily quadrupedal walkers and runners. Occasionally they use their tail for anchoring while moving, however it is mostly used for positioning. The tail is also used for hanging and gripping while feeding or playing and even for picking up objects. These monkeys display a broad range of locomotion patterns such as quadrupedal walking and running, climbing, walking on two legs (bipedalism), leaping or jumping, or controlled drops to a lower location (Defler 1999; Emmons & Feer 1990; Kinzey 1997; Nowak 1999; Welker & Schafer-Witt).

Communication and Perception

Food Habits

Diet of Lagothrix lagotricha consists mainly of fruits, supplemented by leaves, seeds, and some insects. Consumption of leafy material accounts for probably less than 20% of their diet. A large part of their feeding time is spent eating ripe fruit. Seeds are most important early in the rainy season when ripe fruit is not readily available. During July in Amazonian Brazil, insects comprise an important part of the diet. In captivity, female common woolly monkeys were observed to prey on sparrows and were observed to share some of the prey. Higher ranking animals in a troop often take food from lower ranking animals (Eisenberg 1989; Emmons and Feer 1990; Kinzey 1997: Moynihan 1976; Nowak 1999).

  • Animal Foods
  • insects
  • Plant Foods
  • leaves
  • seeds, grains, and nuts
  • fruit

Economic Importance for Humans: Positive

The meat of common woolly monkeys is a highly sought after food by locals living near monkey populations. In Brazilian Amazonia, the skins of Lagothrix lagotricha are used for wall decoration and to make a device, called a cuica. This is used to mimic jaguar calls. Stuffed monkeys are also popular and are found in many homes. Common woolly monkeys are also sought as pets in certain areas and can be bought for around $80 U.S. dollars each (Nowak 1999; Marsh & Mittermeier 1987).

Economic Importance for Humans: Negative


Conservation Status

These animals are a food source for indigenous tribes and are killed mainly for this reason. These monkeys are considered the most intensely hunted monkeys in South America and they have become extinct in many areas. Common woolly monkeys are unable to maintain stable populations under extreme hunting pressure. This species is very sensitive to disturbances in vegetation and their low reproductive rate makes them vulnerable to local extinction. In addition, the mother is normally killed to capture her infant and it is estimated that at least 10 females are sacrificed for every live individual that reaches the market. Many have argued that the common woolly monkey should be designated as an endangered species, but this has not yet occurred (Emmons & Feer 1990; Marsh & Mittermeier 1987; Nowak 1999.


Ivan Stone (author), St. Lawrence University, Erika Barthelmess (editor), St. Lawrence University.



living in the southern part of the New World. In other words, Central and South America.

World Map


Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.


uses smells or other chemicals to communicate

  1. active during the day, 2. lasting for one day.
dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates


animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.


forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.


an animal that mainly eats fruit


An animal that eats mainly plants or parts of plants.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).


having the capacity to move from one place to another.


This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.


rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

seasonal breeding

breeding is confined to a particular season


reproduction that includes combining the genetic contribution of two individuals, a male and a female


associates with others of its species; forms social groups.


uses touch to communicate


Living on the ground.


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.


Defler, T. 1999. Locomotion and posture in Lagothrix lagotricha. Folia primatologica, 70 (6): 313-327.

Eisenberg, J. 1989. Mammals of the Neotropics. Chicago, IL: University of Chicago Press.

Emmons, L., F. Feer. 1990. Neotropical Rainforest Mammals. Chicago, IL: University of Chicago Press.

Kinzey, W. 1997. New World Primates. New york, NY: Aldine De Gruyter.

Marsh, C., R. Mittermeier. 1987. Primate Conservation in the Tropical Rain Forest. New York, NY: Alan R. Liss, Incorporated.

Moynihan, M. 1976. The New World Primates. Princeton, NJ: Princeton University Press.

Nowak, R. 1999. Woolly Monkeys. Pp. 538-540 in Walker's Mammals of the World, 6th Ed.. Baltimore, MD: The John Hopkins University Press.

Welker, C., C. Schafer-Witt. 1989. New World Monkeys. Pp. 162-163 in Grzimek's Encyclopedia of Mammals. New York, NY: McGraw-Hill Publishing Company.