Blue wildebeest
- The maximum lifespan of the brindled gnu in captivity is 24.3 years. The average lifespan in captivity is 20 years.
- Hybrids of the brindled gnu have congenital anomalies related to teeth, horns, and interstitial skull bones. In another study, their size was found to be larger than that of either parent species.
- Male brindled gnus can mate only after 2.5 years. Although they reach sexual maturity much earlier, they can only mate 2.5 years after birth.
- The blue wildebeest undertakes one of the largest mammal migrations.
- Adult male brindled gnus weigh from 170 to 410 kg, and females weigh from 140 to 260 kg. Males are significantly heavier than females, and this is achieved at the age of adulthood.
- Adult male brindled gnus mark an area with secretions from the preorbital glands, but not the entire boundary, only in some places. The size of such an area rarely exceeds 100–120 m in diameter.
- Male brindled gnus are larger and darker than females. They also have thicker horns.
- At night, brindled gnus lose their ability to defend themselves and become vulnerable to predators. During panic, they cannot effectively fend off predators, as they lose balance during jumps.
- Can give birth standing.
- Speed up to 80 km/h.
Age
Blue wildebeest, also known as brindled gnus or white-bearded wildebeest, have a typical lifespan of from 15 to 20 years, with a maximum recorded lifespan of 24 years and 4 months, and a theoretical lifespan ranging from 12 years and 2 months to 24 years and 4 months. The species reaches sexual maturity at an age between 1 year and 2 months and 4 years; the young are born with their eyes open and begin walking immediately. The embryo develops inside the mother, and the calf quickly stands and follows its mother within a herd during the calf stage, which lasts from 1 day to 7 months. The adult stage begins when the animal is capable of reproduction and lives in large herds, lasting from 3 to 20 years.
Phenotype
The blue wildebeest has light and soft fur; the young have this feature. The species possesses a powerful body with grey-blue fur and dark vertical stripes. A beard is formed by the hairs on the lower jaw. The adult animals have thick, curved horns with rings at the base, and also possess a rigid dark mane along the neck.
Physiology
The blue wildebeest stands from 17.8 centimeters to 4.5 meters tall, with a body length ranging from 1.2 to 1.5 meters and a mass between 104.72 kilograms and 0.25 metric tons; the embryonic stage has a body mass of 5 to 22 kilograms; the young have a body mass of 18 to 28 kilograms and a body length of 80 centimeters to 1.1 meters; adult individuals weigh from 140 to 220 kilograms and measure 1.2 to 1.4 meters in body length.
Habitat
The blue wildebeest occupies an elevation range of 0.9 to 1.8 kilometers above sea level and inhabits temperate grasslands with abundant grass and few trees, as well as tropical savannas characterized by heat and uneven rainfall with plentiful grass and trees; the species is found in diverse landscapes including dry land, highlands and tundra, deserts and semi-deserts, terrestrial meadows and steppes, terrestrial herbaceous areas, and terrestrial tidal zones. The climate varies across its habitat, encompassing hot steppes with very hot, dry summers and abundant grass, extremely arid conditions with rare rainfall, winters with minimal precipitation and more summer rain, hot conditions with limited winter rainfall and frequent summer rains, and consistently hot weather throughout the year with frequent but sometimes scarce rainfall.
Shelter
The blue wildebeest inhabits open savanna and the species has no permanent or long-term shelter; for protection from predators and rest, the blue wildebeest uses grass, as it does not have a permanent shelter.
Geography
The blue wildebeest occupies the Afrotropical realm and is found in several ecosystems, including Southern thickets and Acacia-Commiphora woodlands, the West Congo forest-savanna, the Limpopo Lowveld, the Kalahari xerophytic savanna, the Kalahari acacia forests, and Angola’s mopane sparse forests.
Feeding
The blue wildebeest primarily feeds on grass and spends a considerable amount of time grazing to obtain food; its feeding strategy is grazing, and it uses its wide mouth to graze plants close to the ground. The species’ diet consists of grass, young shoots, young growth, and sprouts. The daily food requirement ranges from 4 kilograms to 7 kilograms. Calves consume milk. Predators that hunt the blue wildebeest include leopards, cheetahs, spotted hyenas, and true crocodiles.
Reproduction
The blue wildebeest reproduces through live birth, with the female giving birth to a single calf after a gestation period of 8 months and 2 weeks; the young stand on their feet within minutes of being born. The species inhabits and develops on land, outside of bodies of water. The female has one offspring per pregnancy. Sexual maturity occurs between 2 and 4 years of age. The interval between reproduction is from 1 to 2 years. A litter has 1 calf.