Cacajao calvusred uakari

Geographic Range

Found in the upper Amazonian region of western Brazil, eastern Peru and possibly in southern Colombia.

Habitat

Uakaris are found only in the tropical forests that are either constantly or seasonally flooded, and mostly along small rivers and lakes within the forest.

Physical Description

Members of this cat-sized species of New World Monkey have a head and body ranging between 360-570 mm in length. Their short and somewhat stumpy, nonprehensile tail adds just an extra 137-185 mm. They have a broad flat face and extremely separated nostrils. Their teeth consist mainly of broad flat molars and large canines. They have naked, crimson faces and ears with the rest of their body covered in wispy hair. The various sub-species differ in the color and markings of their fur, ranging from very dark to almost white. Uakaris have long furry fingers and toes that lack claws.

  • Range mass
    2 to 3 kg
    4.41 to 6.61 lb
  • Range length
    360 to 570 mm
    14.17 to 22.44 in

Reproduction

Uakaris are mostly monogamous.

Most uakari females begin reproducing at the age of three, whereas the males don't begin until the age of six. The females give birth to single live young at intervals of about two years. The young are weaned between 3 and 5 months during which period they begin to eat soft fruits.

  • Breeding interval
    Females give birth once every two years.
  • Average number of offspring
    1
  • Average number of offspring
    1
    AnAge
  • Average gestation period
    182 days
    AnAge
  • Range weaning age
    3 to 5 months
  • Average age at sexual or reproductive maturity (female)
    3 years
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    1204 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    6 years

Females nurse their young until they are between 3 and 5 months old.

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

Lifespan/Longevity

Behavior

Uakaris are active and intelligent primates that live in large social groups ranging primarily between 10-30, but sometimes reaching nearly 100. Despite this large size, uakaris split off into groups of 1-10 to do their foraging. They are diurnal and at night climb into high thin branches to sleep. Uakaris are normally quiet but tend to let out loud shrieks to communicate and to mark their territories. They are playful primates, especially the young, who often engage in thier own "games".

Uakaris walk and run quadrupedally on the ground and along branches, but are also good at bounding and jumping bipedally.

Communication and Perception

Food Habits

Uakaris feast primarily on seeds of immature fruits, ripe fruits, leaves, nectar, and a few insects including the caterpillar.

During the rainy season, uakaris spend most of their time high in the trees eating the fruits. In the dry season, they come to the forest floor to forage for seedlings and fallen seeds.

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

Economic Importance for Humans: Positive

Being closely related to humans, uakaris can be useful in studying public health. For example, they can provide information on new vaccines and diseases, such as diabetes, malaria, yellow fever, AIDS, mental disorders and even some cancers. Uakaris are also a valuable provider of meat in Peru and a source of hunting bait in Brazil.

Economic Importance for Humans: Negative

While there is no obvious negative effect on humans by the uakaris, huge amounts of money are used each year to help preserve their habitat.

Conservation Status

Uakaris are on the verge of extinction due to several factors, including the fact that they are hunted for food and for bait. More important, they are rapidly losing their habitat due to the activities of the timber industry. Tropical rainforests are the only areas in which uakaris can live, as is true of many other species endangered for the same reason. The WWF is currently doing everything it can to protect these areas.

Other Comments

The life span of the uakaris typically ranges between 15 and 20 years.

Contributors

Ali Felton-Church (author), University of Michigan-Ann Arbor, Phil Myers (editor), Museum of Zoology, University of Michigan-Ann Arbor.

Glossary

Neotropical

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

World Map

arboreal

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.

chemical

uses smells or other chemicals to communicate

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

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.

frugivore

an animal that mainly eats fruit

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

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).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

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

rainforest

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.

sexual

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

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

viviparous

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

References

October 3, 1996. "ARKive: KngIndex" (On-line). Accessed October 14, 1999 at http://www.arkive.org.uk/species96/White_Uakari/White_Uakari.html.

Alonso, A. November 30, 1994. Accessed October 14, 1999 at http://www-bcf.usc.edu/~aalonso/Academic/primate.html.

Bobe, R. Spring 1998. "Antrho 314 Notes" (On-line). Accessed October 13, 1999 at http://webdancer.sonoma.edu/people/bobe/quiz1notes.html.

Lovett, S. April 5, 1998. "Apes and Monkeys" (On-line). Accessed October 13, 1999 at http://www.monkeymadness.com/apes_monkeys/bbm23.htm.