Bald Uakari

Bald Uakari

Bald-headed uakari, Red uakari, Scarlet fever uakari

Cacajao calvus
Population size
Life Span
15-30 yrs
2.8-3.5 kg
44-4.6 cm

The Bald uakari is a South American primate with a rather unusual appearance. Thus, this animal exhibits a bright red, wide and flat face. Another characteristic feature of this animal is its extremely short tail. The Bald uakaris are believed to have developed this unique color pattern of this face as a result of malaria, which is a common disease in their Amazon rainforest habitat: those with bright red faces are considered to display healthiness, while those with paler faces have definitely contracted malaria and lack the natural immunity to this disease. Hence, these sick animals are typically left without mates.


The natural habitat of this species stretches throughout Amazonian region of western Brazil, eastern Peru and in southern Colombia, where these animals inhabit exclusively tropical forest. Some of these forests are constantly flooded, while others - only during a particular season. Within this habitat, Bald uakaris usually occur along small rivers and lakes.

Bald Uakari habitat map



Climate zones

Habits and Lifestyle

Bald uakaris are highly social creatures, forming groups of 10 - 30 individuals, although these primates have been observed in larger units of up to 100. When foraging, these groups divide into smaller sub-groups of 1 - 10 animals. As diurnal animals, bald uakaris sleep during the nighttime high in thin tree branches. They use all of their four legs, when walking and running both on the ground and in trees. When bounding and jumping, they use only two legs. Bald uakaris communicate and mark their home ranges through loud shrieking calls, although these animals are generally quiet. Bald uakaris are not only intelligent, but also very active and playful animals. They spend a lot of time playing various games, particularly young individuals.

Diet and Nutrition

These primates are herbivores (frugivores). Their diet generally consists of immature fruits, ripe fruits, leaves, nectar as well as a few insects such as the caterpillar.

Mating Habits

6 months
1 infant
3-5 months

Bald uakaris are monogamous, which means that one male mates with one female exclusively. They typically breed between October and May. Females yield a single baby after 6 month of gestation. The newborn infant is helpless and very small. During the first few months of its life, the baby feed exclusively upon maternal milk and is clung to its mother. At 3 - 5 months old, the infant starts taking soft fruits and is subsequently weaned. Females of this species first mate at 3 years old, whereas males start mating at 6 years of age.


Population threats

Currently, Bald uakaris primarily suffer from destruction of their natural habitat. Another big threat is hunting, which generally affects populations in some parts of Peru and Brazil. These primates are hunted mainly for food and as bait. Living in riverine forests, they are easy prey for hunters, which move through the forests by canoes.

Population number

No estimate of population size is available for Bald uakaris. Today, this species’ numbers are decreasing, and the animal is classified as Vulnerable (VU) on the IUCN Red List.

Fun Facts for Kids

  • The diet of these animals varies, depending on season. Thus, as the rainy season comes, they typically spend the majority of their time consuming fruits high in trees. During the dry season, these primates descend to the forest floor, where they feed upon various seedlings and fallen seeds.
  • The word 'uakari’ is pronounced ‘wakari’.
  • These animals exhibit the shortest tails of all American monkeys.
  • Bald uakaris are able to easily split thick fruit skins with their developed fangs.
  • The Bald uakari is a medium-sized species with a red face. Although this coloration may seem to be rather weird, it actually attracts mates. Usually, individuals with the reddest faces are the most attractive ones.
  • The strong jaws and sharp teeth allow these primates to crack tough nuts, which other monkeys cannot open.
  • When excited, this animal wags its very short tail.
  • They are known to give out an unusual vocalization, resembling a hysterical laughter.
  • When threatened, Bald uakaris typically erect their fur, emit clicking sounds and wag their tails.
  • The communication system of these primates includes 10 various facial expressions.
  • Baby Bald uakaris have gray colored faces.
  • Although the color of their face is generally red, it can occasionally change to display certain emotions.


1. Bald Uakari Wikipedia article -
2. Bald Uakari on The IUCN Red List site -

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