Black-horned capuchin  (Cebus nigritus)

The black-horned capuchin is classified as Near Threatened (NT) on the IUCN Red List (1) and listed on Appendix II of CITES (3).

The charismatic black-horned capuchin (Cebus nigritus) is easily identifiable by the presence of two black ’horn-like’ tufts of hair on the heads of the adults. One of the larger of the capuchin monkeys, the black-horned capuchin has very dark brown or black fur on the body, which contrasts with areas of white around the cheeks and forehead, and some individuals have slightly lighter brown fur on the chest and neck (4). All capuchin monkeys have a prehensile tail, which helps them move with speed and agility through the trees (5). 

The black-horned capuchin occurs in southern Brazil and north-east Argentina (1).

This primate inhabits lowland, coastal, montane and sub-montane forest (1).

The black-horned capuchin is a social monkey that lives in groups of approximately 6 to 20 individuals, which typically comprise more females than males. Hierarchies exist within both the males and females of the group, with the alpha (dominant) female being submissive to the alpha male (1).

The female gives birth to a single young at a time after a gestation period of 151 to 155 days. If the young survives, the female will give birth again two years after the young has been weaned; however, if the infant dies, the female may reproduce much sooner. Females reach sexual maturity at the age of four, while males usually become sexually mature a few years later (6).

Capuchin monkeys are the most omnivorous of the Neotropical (tropical American) primates, having an extremely varied diet consisting of fruit, other plant matter, insects, spiders and small mammals (7). There have been sightings of capuchin monkeys hunting for small rodents, although most of the meat in their diet is thought to come through the foraging of carcasses (8). The black-horned capuchin spends 70 to 90 percent of its day foraging for food (2).

Although little is known about tool-use in the wild, advanced behaviour in tool making has been documented numerous times in black-horned capuchins in captivity, such as making modified twigs to probe holes and the use of stones to crack open ice cubes to retrieve hidden food (9).

As with many primates, communication between members of a black-horned capuchin group consists of a wide range of different verbal communications, body language and facial expressions. One particular method of communication documented within this species is the ‘scream embrace mechanism’, a loud, high-pitched call followed by an embrace which tends to be used to reunite members of the group after prolonged absences. This occurs most frequently between the males of the group (10).

The major threats facing the black-horned capuchin today are hunting, capture for the pet trade, and the destruction of its habitat, mainly for agriculture, transport, logging and urban growth. Historically a wide ranging species, its numbers are now declining rapidly, and although exact population numbers are unknown, it is now relatively scarce outside of large protected areas (1).

The black-horned capuchin occurs in a number of protected areas across its range, including Iguazu National Park, Argentina (1). Small areas of forest around research stations are also afforded protection, although are not large enough to make a recognisable difference on the number of black-horned capuchins, and much more must be done to prevent the continued decline of this charming species (11).

View information on this species at the UNEP World Conservation Monitoring Centre.

For more information on primate conservation see:

• IUCN/SSC Primate Specialist Group:
  http://www.primate-sg.org/pc.htm
• Neotropical Primate Conservation: 
  http://neoprimate.org/lang/en

To learn more about wildlife conservation in Brazil see:

• Wildlife Conservation Society:
  http://www.wcs.org.br/