Hartebeests

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Hartebeests

Hartebeests are even-toed hoofed antelopes in the family Bovidae, which are found throughout Africa south of the Sahara. Included among the grazing antelopes in the subfamily Hippotraginae are the reedbucks,

waterbuck, rhebok, addax, oryx, bluebuck, gemsbok, and roan and sable antelopes. More closely related to hartebeests are the impala, topi, wildebeest, and bonte-bok. These are medium to large antelopes that forage for food in the grasslands and woodlands of Africa.

Both males and females have characteristic hooklike horns ringed with ridges. Hartebeests range from a tan to a reddish brown color with distinctive markings denoting the different species. Females are slightly smaller than males. Hartebeests have long faces, raised high shoulders with strong legs in front, and a steep sloping back. Their legs are thin and they canter for long distances, which is made possible by their long forelegs.

Social groups and behavior

Hartebeestes graze in herds and are commonly seen with wildebeests, gazelles, and zebras. The home ranges of hartebeests can be from 800 to 1,400 acres (234–567 hectares). Within this area a number of different relationships exist. Small groups within the home range may occupy only the few acres that a male can defend. The female groups roam over many of the male-dominated smaller territories. Young hartebeests remain with their mothers, who may have several offspring of different ages following her. Males leave around the age of two and a half years old and join bachelor herds.

Females are sexually mature at two years of age. Pregnancy lasts about eight months and hartebeests give birth to one offspring at a time. Newborns lie out in the grass for about two weeks, and then join the maternal herd. Mothers will defend young males from threatening older males that claim the territory.

Hartebeest males mark their territories with dung piles. They will also advertise their territorial claim by standing on mounds within the territory and marking grass with their preorbital glands, which are located in front of their eyes. They also have scent glands on their front hooves.

Hartebeests may settle territorial differences by fighting or by ritualized behavior. This may include defecation, pawing the ground, and scratching and cleaning their heads and necks. Fighting can include something that looks like neck wrestling. One of the difficulties hartebeests encounter in maintaining control of their territories is their need for water. If one leaves to drink, on his return he may find that another bull has claimed his territory.

KEY TERMS

Forage —Vegetation that is suitable for grazing or browsing animals.

Home range —The full territory that an animal occupies throughout its lifetime.

Land competition —When two or more animal groups use the same natural growth on a land area and one population grows while the other declines.

Land competition

While hartebeests once occupied a large area over much of the African continent, their range has diminished because of expanded farming in some of the areas they had once inhabited. Since domestic cattle graze on the same grasses that hartebeests prefer, the growth in cattle raising in Africa has resulted in a general decline in hartebeest populations. The most numerous species is the Kongoni or Coke’s hartebeest (Alcelaphus buscelaphus cokii) of Kenya, while the red hartebeest (A. b. caama) survives in protection on farms. The bastard hartebeests (Damaliscus spp.) are smaller than the Alcelaphus species, and include the hirola (D. hunteri), the topi (D. lunatus) of East and South Africa, and the blesbok (D. pygrus ) of South Africa.

Particularly vulnerable has been the hirola, or Hunter’s hartebeest. In a five year period from 1973 to 1978, the hirola population in Kenya declined from 10,000 to a little over 2,000. The bubal hartebeest (Alcelaphus buscelaphus buscelaphus) became extinct in 1940 and in 1969 the Lake Nakuru hartebeest was lost to the continent. The Swayne’s hartebeest (Alcelaphus buscelaphus swaynei) was abundant in the early part of this century and is now considered the most vulnerable to extinction. The red hartebeest or caama has been rescued, replenished on farms and in game parks, and released again on natural ranges.

In addition to the competition for land, hartebeests face threats from predators. They are particularly vulnerable to lions, leopards, cheetahs, and hyenas. Young animals are also vulnerable to attacks from jackals, pythons, and eagles. Hartebeests get their name from the South-African, Dutch-derived language of Afrikaans. It means “tough beast.” The early Dutch settlers of South Africa found them to be good runners that could not be easily overtaken by a horse.

See also Antelopes and gazelles.