The black bearded saki (Chiropotes satanas ) is a species of bearded saki, native to the Amazon rainforest in South America, specifically to an area of north-eastern Brazil. Black Bearded saki are of the Platyrrhine infraorder, also known as New World monkeys. They are from the Pitheciidae family and Chiropotes genus. This species is one of five species of Chiropotes or bearded sakis remaining. Bearded sakis are medium-sized (50 cm), mostly frugivores, specialised in seed predation. The genus name Chiropotes means "hand-drinker" as they have been observed using their hands as ladles for scooping water into their mouths. This behavior is thought to be a way of maintaining and protecting their magnificent beards. Black bearded sakis habitat has been subdued to heavy habitat fragmentation making the future conservation status of the species unknown.
Black bearded sakis can be identified by their thick black hair, distinctive beard that shapes the face, and a bushy fox-like. Their tail is non-prehensible and use quadruple movement for locomotion. Black bearded sakis have some yellowish-brown highlights around the back and shoulders and can weight from 2 kg to 4 kg. Sexual dimorphism results in males being slightly larger than females and also have a bulging forehead. Formerly red-backed, brown-backed and Uta Hick's bearded saki, the other member of the genus Chiropotes, where catalogued as subspecies or taxonomically insignificant variations (in which case the 'combined' species simply was called the bearded saki), but based on color of pelage, karyotype, and molecular analysis it has been recommended treating these as separate species. The black bearded saki is the only dark-nosed species of bearded saki with a blackish back, though some females and young have a paler, brownish back. Black bearded saki's teeth have evolved for seed predation: these dental adaptations allow then to crack and access seeds in extremely hard pods. They open hard-shelled fruits in a specialized, efficient process using their teeth.
Black bearded sakis are endemic to the far eastern Amazon in Brazil, in a range restricted to a relatively small region from the Tocantins River in Pará east to around the Grajaú River in Maranhão (similar to the range of the equally threatened Kaapori capuchin). The natural home range of bearded sakis can vary from 200 to 250 ha. This is the only Amazonian pitheciidae found east of the Rio Tocantins is the Black bearded Saki. Studies show that Bearded sakis can adapt to a reduction in their habitat.
Black bearded sakis spend most of time resting, traveling and eating. Black bearded sakis use mostly quadruple movement to move in the canopy of trees. As infants the monkeys can be seen using their tail to grasp things but lose the ability as they mature.
They are social animals commonly grooming and playing with one another, even with those of other primate species. Black Bearded sakis can be found in troops of 20 - 30 individuals. Individuals of a troop will separate and rejoin throughout the day, have large home ranges, and travel long daily distances.
Black bearded sakis are highly frugivore, specialized in seed predators as 90% of their diet comes from fruits and its seeds. Black bearded sakis feed mostly on plants like Sapotaceae, Lecythidaceae, and Chrysobalanaceae families but they can feed on more than 100 species as well as adapt their diets. They complement their diets with fleshy fruits and small insects. Black bearded sakis can use their strong canine teeth to crack open hard shells of fruits and nuts enabling them to access the unripe seeds inside the fruits.
Bearded sakis have a gestation period of 5 months and produce one young at a time. They don't become sexually mature until 4 years old and have an expected lifespan of 18 years. Black bearded sakis give birth to offspring every 2 years.
Black bearded sakis are a critically endangered species. Just over the last few decades urbanization in the Brazilian amazon has brought with it highways, agriculture, and dams creating an influx in habitat fragmentation, habitat destruction and poaching pressure. Habitat fragmentation is rising as secondary roads increase and people move into uninhabited areas of the amazon rainforest. Along with an influx of people the amount of agriculture required to support the area increases, augmenting the pressure for deforestation.
