The Celebes Crested Macaque (Macaca nigra), also known as the Black "Ape", is an Old World monkey that lives in the northeast of the Indonesian island Sulawesi (Celebes) as well as on smaller neighboring islands.

Their skin and hairless face is, with the exception of some white hair in the shoulder range, entirely jet black. The long muzzle with high cheeks and the long hair tuft, or crest, at the top side of the head are remarkable. The tail is only approximately 2 cm of stub. With a total body length of 45 to 60 cm and a weight of 7 to 10 kg, they are one of the smaller macaque species.

Celebes Crested Macaque are diurnal rain forest dwellers. They sleep and search for food in trees, but socialize and spend most of their time on the ground. They live in groups of 5 to 25 animals. Smaller groups have only a single male, while larger groups have up to four males. The females, however, always outnumber the males 4:1. Since young males must leave their birth group maturity, they sometimes form bachelor groups before they look for a connection to an existing mixed group. Communication consists of various sounds and gestures. For example, the presentation of the long eyeteeth while grimacing a clear threatening gesture.

The diet of the monkeys consists of fruits, leaves and buds, altough they also eat bird eggs and insects (such as caterpillars).

The receptivity of the females is clarly indicated by a swelling and redness which, in contrast to the black skin color, is particularly remarkable. The gestation time is approximately six months, and the birth of the usually single offspring happens in the Spring, since food is more plentiful then. Young animals are nursed approximately one year and become fully mature in 3 to 4 years, females somewhat sooner than males. Their life expectancy is estimated at approximately 20 years.

Celebes Crested Macaque are hunted sometimes both as pest, because they devastate crops and fields, as meat. Clearing the rain forests represents an additional problem. Their situation on the small neighbour islands of Sulawesi (for example Bacan) is somewhat better, since these are hardly settled.