Cacajao calvus
red uakari

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

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.

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.

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.

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.

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.

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.

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.

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