Bongo (antelope) - Social Organization and Behavior

Social Organization and Behavior

Like other forest ungulates, bongos are seldom seen in large groups. Males, called bulls, tend to be solitary while females with young live in groups of 6 to 8. Bongos have seldom been seen in herds of more than 20. Gestation is approximately 285 days (9.5 months) with one young per birth with weaning at 6 months. Sexual maturity is reached at 24–27 months. The preferred habitat of this species is so dense and difficult to operate in that few Europeans or Americans observed this species until the 1960s. Current living animals derive solely from Kenyan importations made during the period 1969–1978.

As young males mature and leave their maternal groups they most often remain solitary, although rarely they join-up with an older male. Adult males of similar size/age tend to avoid one another. Occasionally they meet and spar with their horns in a ritualised manner and rarely serious fights will take place. However, such fights are usually discouraged by visual displays, in which the males bulge their necks, roll their eyes and hold their horns in a vertical position while slowly pacing back and forth in front of the other male. They seek out females only during mating time. When they are with a herd of females, males do not coerce them or try to restrict their movements as do some other antelopes.

Although mostly nocturnal, they are occasionally active during the day. However, like deer, it may be that bongos may exhibit crepuscular behaviour. Bongos are both timid and easily frightened; after a scare a bongo moves away at considerable speed, even through dense undergrowth. They seek cover, where they stand still and alert, facing away from the disturbance and turning their heads from time to time to check on the situation. The bongo's hindquarters are less conspicuous than the forequarters, and from this position the animal can quickly flee.

When in distress the bongo emits a bleat. It uses a limited number of vocalisations, mostly grunts and snorts while females have a weak mooing contact-call for their young. Females prefer to use traditional calving grounds restricted to certain areas, while newborn calves lie in hiding for a week or more, receiving short visits by the mother to suckle.

The calves grow rapidly and can soon accompany their mothers in the nursery herds. Their horns grow rapidly and begin to show in 3.5 months. They are weaned after six months and reach sexual maturity at about 20 months.