Wildebeest

The blue wildebeest is a large, broad-shouldered antelope with a muscular, front-heavy build, found on short-grass plains bordering bush-covered acacia savannas in southern and eastern Africa. Its coat ranges from deep slate or bluish-grey to light grey, and both sexes carry large curved horns. It grazes mainly on short grasses and forms loose herds of fast, wary animals. Three African populations make long-distance migrations timed to the annual pattern of rainfall and grass growth, which gives them nutrient-rich forage for lactation and calf growth. The population is estimated at around 1.5 million.

About the wildebeest

The blue wildebeest, Connochaetes taurinus, is a large, cow-like antelope of the family Bovidae. It is one of two wildebeest species, alongside the black wildebeest, and lives on the grassy plains and acacia savannas of southern and eastern Africa, where some herds make vast seasonal migrations.

It goes by several names: common wildebeest, white-bearded gnu and brindled gnu. "Blue" refers to the silvery-blue sheen of the coat, and "gnu" comes from the name used by the Khoikhoi people of southwestern Africa. The genus name Connochaetes combines Greek words for "beard" and "flowing hair," and taurinus comes from the Greek for bull.

The body is built front-heavy. Broad shoulders, a muscular neck and a robust, wide muzzle give the animal a bovine look despite being an antelope. Adults range from deep slate or bluish gray to light gray or grayish brown, and dark vertical stripes run from the neck to the back of the ribcage, which is where "brindled" comes from. The mane is long, stiff and jet black, matching the face and the long black tail, which measures 60–100 cm (2–3.3 ft). Depending on subspecies, the beard is creamy white or black. Calves are born tawny brown and start turning adult colors at about 2 months.

Both sexes carry horns shaped like a pair of parentheses. They sweep out to the sides and then curve up and in, reaching 83 cm (33 in) in males and 30–40 cm (12–16 in) in females. Males are larger and darker than females. Five subspecies are recognized, from the common wildebeest of southern Africa to the white-bearded forms of Kenya and Tanzania.

Behavior and diet

Blue wildebeest are most active in the morning and late afternoon and rest through the hottest hours. In Serengeti National Park, one study found them resting over half the time, grazing a third of it, and walking about 12 percent. They are extremely wary and agile, reaching up to 80 km/h (50 mph) when they run.

They are grazers built for short grass. The broad mouth crops large amounts of it, and they feed by day and on moonlit nights. When grass runs out they browse shrub and tree leaves. Wildebeest often graze alongside plains zebras, which eat the taller, coarser grass and expose the greener growth wildebeest prefer. They like to drink twice a day and take in 9–12 liters (2.4–3.2 US gallons) every one to two days. Even so, they can survive in the Kalahari by getting water from melons, roots and tubers.

Herds are loose. Female calves stay with their mothers and related females for life, and in the wet season the females lead the herd to the best grazing. Most young males join bachelor herds, and bulls become territorial at four or five years old, marking their patches with dung piles, scent and displays that include pawing, rolling, bellowing and a nasal "ga-noo" call. A male's bellow can carry up to 2 km (1.2 mi).

The three-week rut starts at the end of the rainy season, often on the night of a full moon, and conception rates can reach 95 percent. After about 8.5 months, 80–90 percent of calves are born within the same three weeks. Females give birth in the middle of the herd at midday, and calves weigh about 19 kg (42 lb). A calf can stand and nurse within minutes. Young males leave their mothers at about 8 months.

Wildebeest are major prey for lions, cheetahs, leopards, African wild dogs, spotted hyenas and Nile crocodiles. Threatened herds bunch together, stamp and give shrill alarm calls, and mothers often fend off a lone hyena or cheetah.

Range and habitat

The blue wildebeest is native to Kenya, Tanzania, Botswana, Zambia, Zimbabwe, Mozambique, South Africa, Eswatini and Angola. It has died out in Malawi but has been reintroduced to Namibia. The Orange River marks the southern edge of the range, while Lake Victoria and Mount Kenya bound it to the west.

Its favorite habitat is short-grass plains next to bush-covered acacia savanna, in country neither too wet nor too dry. It also uses areas from dense, overgrazed bush to open woodland floodplains, but avoids montane grassland and miombo woodland. It can tolerate dry country as long as drinking water lies within about 15–25 km (9–16 mi), and is rarely found above 1,800–2,100 m (5,900–6,900 ft).

Three populations still make long-distance migrations: the Serengeti, Tarangire and Kafue herds. They follow the rains and new grass, moving to dry-season ranges when water runs out and back to wet-season ranges when the rains return. Many other long-distance migrations existed a century ago, but all of them have since been disrupted, cut off and lost.

Blue wildebeest vs black wildebeest

The two wildebeest species split about a million years ago. Differences in habitat and social behavior normally keep them apart, but they can interbreed when confined in the same area. The offspring are usually fertile, and one study of hybrids found many with abnormalities of the teeth, horns and skull.

Conservation status

The blue wildebeest is listed as Least Concern on the IUCN Red List. Published estimates of the total population disagree. One puts it at around 1.5 million with a stable trend, while counts in Serengeti National Park in Tanzania, where the species is most plentiful, have risen to about 1.3 million. It is widespread and is being introduced to private game farms, reserves and conservancies.

Local declines are serious, though. In the Maasai Mara ecosystem, numbers fell about 80 percent, from roughly 119,000 in 1977 to about 22,000 twenty years later, mainly because farms took over wet-season grazing and calving grounds. The Tarangire migration has also dropped sharply. The eastern white-bearded wildebeest, one subspecies, is down to roughly 6,000 to 8,000 animals.

Threats include deforestation, drying water sources, spreading settlements, poaching and cattle diseases. Fences across migration routes have caused mass die-offs in droughts, when herds were cut off from water and grazing.