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The Bontebok is a rare, medium-sized antelope (males weigh 68–86 kg and females about 56 kg) which is restricted in range to the coastal plain of the south western Cape district of South Africa. The largest herd in existence, consisting of about 250 animals, was studied for 15 months in the Bontebok National Park. Mating is seasonal, occurring in January to March. Females are in oestrus for only about 24 hours and will consort with any male during this time but due to the strongly territorial social system will often be restricted to the territory of a single male. Copulation is repeated many times during the oestrus period and is similar to that described for other members of the Bovidae.

The social structure consists of territorial males, very small nursery herds of females and young and a bachelor herd of up to 100 males of all ages. Calving is also seasonal and one birth was witnessed. Females remain with the herd during parturition. There is no lying out behaviour and calves follow their mothers from birth. Calves spent 80–90% of their time lying down for the first two weeks of their life and suckle every one to two hours. Calves less than five days old suckle for significantly longer than older calves.

Summary

Mating and parturition in Bontebok are strongly seasonal and gestation is about eight months. Most adult females with their young spend their time grazing on the territory of a territorial male in small nursery herds. The male pays attention to all females on his territory and addresses his courtship display to each of his females frequently at all seasons of the year. A female comes into oestrus for about 24 hours and will copulate many times with any male during this period though often she may remain on the territory of a single male. The male and the oestrus female may remain slightly apart from the other females in the group during the period of her oestrus. Copulation is very brief and is similar to other bovids, consisting of a single ejaculatory thrust. There is a marked lack of precopulatory or postcopulatory displays by the male and copulation is preceded only by the normal courtship display or by no display at all. Normally there are bouts of sexual activity involving many unsuccessful mountings and a few successful copulations interspersed with longer periods of other activities (e.g. grazing). The territorial system ensures that other males do not interfere with mating.

The female calves in the herd and the calf runs with the mother from birth. There is no lying out behaviour. The females eats the foetal membranes but not the placenta which is dropped 4–6 hours later. Calves spend 80–90% of their day lying down during the first two weeks of life but by seven weeks spend 40% of the day grazing. Calves in the age bracket 6–11 days have a total suckling time during the daylight hours of 80–380 seconds. Calves five days old or less suckle for an average 58 seconds per event, while for 6–11 day olds this drops to 24 seconds—statistically a highly significant difference, suggesting a possible critical period for calf survival during its first five days of life. Occasional suckling continues up to the time the calf leaves its mother. Calves of both sexes leave their mothers at the age of about one year. The female pays her offspring little attention after the age of about three weeks and it is up to the calf to stay with its mother. A lost calf utters staccato bleats when looking for its mother.