Golden-Bellied Capuchin, Sapajus xanthosternos
Geographic Distribution and Habitat
The golden-bellied capuchin, also called yellow-breasted capuchins and buffy capuchins, is a New World monkey found mostly in the state of Bahia on the east coast of Brazil. They live in tropical rainforests with annual rainfalls averaging around 71 in (180 cm) and an average temperature of 75°F (24°C).
Size, Weight, and Lifespan
Males are slightly bigger than females. Male golden-bellied capuchins stand at about 15.7 in (40 cm) tall; females are 14.6 in (37 cm) tall. The tail lengths of both sexes roughly match their body lengths. Males are also heavier than females, weighing in at about 8.8 lb (4 kg) compared to the average female weight of 5.5 lb (2.5 kg).
Capuchin monkeys can live between 15 and 25 years in the wild. In captivity, golden-bellied capuchins have been recorded to live up to 30 years old, although some of their capuchin relatives, which are more common in captivity, have lived for up to 50 years.
Golden-bellied capuchins, also called yellow-breasted capuchins, are so named for their golden chest. The rest of their body is covered with fur ranging in color from brown to brick-red, with the exception of a black patch of fur commonly on top of their head. Golden-bellied capuchins were once considered a subspecies of the tufted capuchin due to the subtle tufts of fur around their neck, but their classification was changed in recent decades.
The capuchin’s body is designed for effortless climbing. Their long fingers are widely separated from a stubby thumb, allowing their hands to grab wide branches while still being able to delicately handle small objects like berries and nuts. Their big toe is fully opposable too, so they can grasp a wide variety of limbs. They have a prehensile tail, which helps them stay balanced while traversing the canopy.
Golden-bellied capuchins have a highly diverse diet that changes depending on their location. They eat leaves, flowers, fruits, seeds, nuts, and berries. They may also hunt animals such as insects, birds, bats, amphibians, and reptiles. Capuchins living near bodies of water may also eat various shellfish.
Behavior and Lifestyle
Golden-bellied capuchins are diurnal (active during daylight hours) and primarily arboreal (tree-dwelling). Ideally, they would spend nearly their entire lives in trees, but habitat destruction and fragmentation occasionally require them to traverse the ground. The exceptions to this rule are capuchins who live along rivers and in mangrove forests. These monkeys spend a great deal of time along the water’s edge searching for food (provided there are sentries in place).
Like other capuchin species, golden-bellied capuchins have been observed using stone tools. When a monkey finds a nut they are unable to crack, they will find an embedded rock in the ground to use as an anvil and use a small stone as a hammer to smash the nut open. Researchers theorize that these monkeys have always had the intellectual capacity to use tools, but they have only recently resorted to using them due to food scarcity and habitat destruction.
Although not recognized as a distinct species until recently, the golden-bellied capuchin monkey was the first capuchin species to be described by European scientists around 500 years ago. They were named “capuchins” for their resemblance to capuchin friars.
Golden-bellied capuchins live in groups of 9 to 27 individuals, which consist of multiple males and females. Each group has an alpha male as well as an alpha female. A typical group holds a territory of about 3 sq mi (7.8 sq km), which likely overlaps with other group territories.
The alpha male is dominant over all group members. He is allowed the best foraging spots and gets first mating rights with all of the females, although all group members are allowed to freely mate. The alpha male also receives the most attention while grooming, which is important for group bonding. In turn, the alpha male is expected to take the lead in defending the group’s territory from intruders.
Capuchins are constantly chattering and squealing throughout the day. They have several calls in their repertoire, most of which are meant to alert the others of their own location. When foraging, the entire group of golden-bellied capuchins will be sounding off to make sure everyone is staying close by. They also have specific calls for when they lose sight of the others, which change depending on how long they’ve been lost and how far away they think they are. There are also basic calls meant to signal alarms or threaten others.
Golden-bellied capuchin monkeys also take part in scent-marking. Their favorite method is called “urine-washing,” in which they rub their own urine all over their fur. This makes their scent more potent and longer-lasting as they forage through their territory. They may also rub their chest on tree limbs to send a message to any possible intruders.
Although the alpha male is the most active mater, all adult males and females may freely mate within their group. As food is plentiful year-round, these capuchins in eastern Brazil have no true mating season, but instead mate throughout the year. Females look to mate once every two years, and their gestation period lasts 5 to 6 months.
Mothers almost always give birth to a single infant. There has only been one observed case of twins (both of whom were raised successfully to adulthood). The baby is completely helpless for the first month as it is carried by the mother. The baby clings to the mother’s back for the second month, after which he or she gradually gains independence. The weaning process, and the process to total independence, occurs over a period of 2 to 11 months. The entire group provides assistance to mothers in raising their offspring, with sub-adults taking on more responsibility than others.
Although males do not reach sexual maturity until they are over 6 years old, they will usually leave the group as early as 2 to join a new group. Females, on the other hand, generally stay with their natal group for life. They will reach sexual maturity at around 4 years old, although they will not usually mate for another 2 or 3 years. Most monkeys are usually not physically ready for childbirth at the time of puberty.
Living in one of the world’s premier biodiversity hotspots, golden-bellied capuchins have a wide variety of predators. These predators include boa constrictors as well as other snakes, birds of prey such as the harpy eagle, jaguars, ocelots, and caimans.
Capuchins are also important seed dispersers for their habitat. When they eat the fruits of one tree, they defecate the seeds throughout their territory, leading to a healthier, more diverse rainforest.
The golden-bellied capuchin is listed as Critically Endangered by the International Union for Conservation of Nature (IUCN, 2020). Population: 2,499 mature individuals. The species population has fallen by 80% in the last 50 years, with the majority of the decline being due to habitat destruction as well as hunting. A decrease of an addition 80% is anticipated in the coming 48 years along with at least 50% forest loss.
Like many animals in and near the Amazon rainforest, golden-bellied capuchins suffer from habitat fragmentation. Populations are separated from each other and are prevented from interbreeding. This leads to a lack of diversity and possible inbreeding, which sends populations into an extinction vortex. An extinction vortex occurs when a population decreases to the point where it becomes seriously vulnerable to new threats such as diseases, catastrophes, and inbreeding depressions.
As well as the threats of forest loss, hunting, and the pet trade, as well as threats from potential diseases, such as yellow fever, further place the species in peril.
The remaining habitats of the golden-bellied capuchin are all protected. The biggest of these places is the Una Biological Reserve, which is home to about 185 individuals. These capuchins are often just one of many animals targeted by conservation plans in Brazil. 339 animals are currently listed as Threatened or worse in Brazil, including 34 endangered primate species.
There are thousands of Brazilian environmental activists working hard to preserve their country’s environment, however, environmentalism is a dangerous issue here. In 2017 alone, 57 activists were assassinated Brazil. Brazil is routinely rated as the most dangerous country in the world for conservation workers (although other South and Latin American countries are more dangerous when adjusted for size and population). High-profile assassinations of environmentalists in Brazil include Chico Mendes (1988), Sister Dorothy Stang (2005), and Zé Cláudio (2011).
With this knowledge, it is vital for international groups to help ensure the safety of environmentalists in Brazil so that they may fight to preserve the Amazon rainforest without their lives being endangered. This requires not just funding, but public awareness and the elimination of corruption present in all levels of the Brazilian government. In September 2018, the United Nations partnered with the NGO Global Witness to launch a program to protect environmental defenders in Brazil.
- Flesher, Kevin Michael. “The Distribution, Habitat Use, and Conservation Status of Three Atlantic Forest Monkeys (Sapajus Xanthosternos, Callicebus Melanochir, Callithrix Sp.) in an Agroforestry/Forest Mosaic in Southern Bahia, Brazil.” International Journal of Primatology, vol. 36, no. 6, Dec. 2015, pp. 1172–1197.
- Silva, Fabiana Araújo Da, et al. “Hunting, Pet Trade, and Forest Size Effects on Population Viability of a Critically Endangered Neotropical Primate, Sapajus Xanthosternos (Wied-Neuwied, 1826).” American Journal of Primatology, vol. 78, no. 9, 26 May 2016, pp. 950–960.
Written by Eric Starr, September 2018. Conservation Status updated July 2020.