The bald uakari or bald-headed uakari is a small New World monkey characterized by a very short tail, a bright, crimson face, bald head, and long coat. The bald uakari is restricted to várzea forests and other wooded habitats near water in the western Amazon of Brazil and Peru.

Physical Characteristics

Bald uakaris are easily recognized by their bright red, hairless face and head, which signals health and vitality, as paler faces may indicate malaria infection Animalia+1. Their long, shaggy coat ranges from white to reddish-brown or orange, and they have a very short tail of about 14–18.5 cm (5.5–7.5 in), roughly half the length of their body Wikipedia+1. Adults weigh between 3–3.5 kg (6.5–7.75 lbs), with males slightly larger than females Wikipedia+1. Their powerful jaws allow them to open hard nuts, including Brazil nuts, and consume seeds that other primates cannot Wikipedia+1.

Habitat and Range

Bald uakaris are endemic to the western Amazon, primarily in Brazil and Peru, with possible historical presence in Colombia Animalia+2. They inhabit várzea forests and other seasonally or permanently flooded areas near rivers and lakes. During the rainy season, they remain arboreal, navigating the treetops to avoid floodwaters, while in the dry season they forage on the forest floor Wikipedia+1.

Diet

Their diet is primarily frugivorous, consisting of seeds (67%), fruits (18%), flowers (6%), buds, nectar, and occasionally small animals (5%), Wikipedia+1. They rely on color vision and smell to select ripe fruits and seeds, often sitting on branches to eat. Their strong jaws and specialized teeth allow them to access hard-shelled nuts and unripe fruits Wikipedia+1.

Behavior and Social Structure

Bald uakaris are highly social, forming troops of 10–30 individuals, though larger groups of up to 100–200 have been observed Fact Animal+2. During foraging, these groups often split into smaller subgroups of 1–10 individuals. They are diurnal, moving nimbly through trees and on the ground using all four limbs, and occasionally walking or jumping on two legs Fact Animal+1. At night, they sleep high in the canopy to avoid predators.