SPECIES: Cacajao spp.

PHYSICAL DESCRIPTION: Male Ht. 43.5-48.5 cm Wt. 4.1 kg Female Ht. 36.5-44.5cm Wt. 3.5 kg Coat: Entirely white to chestnut-red, black Skin: Pink or black

Brain size: 74.3cm3 Locomotion: Has no tail (a stump), four grasping limbs, and is capable of moving quadrupedally, through leaping, and pronograde clambering Longevity: 23 years

GEOGRAPHIC LOCATION: South America, flooded swamp forests, Brazil, Colombia, Venezuela, and Peru

ECOLOGY: Habitat: Rainforest in the trees, only on ground to forage Home Range: 3000 ha Day Range: 6 sq. km Population density: 0.4-0.6 sq. km

DIET: Fruits, nuts, plants, insects, and grubs Techniques used to get food: They stay in fruit trees, eat mainly fruit and leaves, and have powerful jaws for nuts

SOCIAL ORGANIZATION: Group size: 7-50, composed of multiple adult and subadult males in addition to females Mating system: Females mate with dominant male and with subdominant Male/female transfer: Unknown Male/female dominance hierarchies: Male in charge Kinship: Familial groups, children leave two years after next infant Territoriality: Yes Foraging Parties: Smaller groups Aggression: Dominant males, but fairly docile

INTELLIGENCE: Very "human-like" capabilities according to caretakers.

REPRODUCTION: Birth seasonality: May-October Male/female age of sexual maturity: Male - 6 years, Female - 3 years Gestation length: 6 months Estrus swellings: None Litter size: 1 Interbirth interval: 2 years Infant birth wt. and mortality rate: Unknown


TOPICS OF SPECIAL INTEREST: Diurnal, only two at Los Angeles Zoo, Jivaro Indians have been known to eat them, and they interact with other species for protection from birds.





Hershkovitz, Philip. Living New World Monkeys. University of Chicago Press. 1977 Volume 1 Chicago.

Leonard, S. and Bennet, C. 1996. Associative Behavior of Cacajao calvus ucayalii with Other Primate Species in Amazonia Peru. Primates Vol. 37(2), 227-230.

Macdonald, David ed. The Encyclopedia of Mammals. Facts on File Inc. New York 1984.

Napier, J.R. A Handbook of Living Primates. Academic Press. New York. 1967.

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