This broad-shouldered antelope has a muscular, front-heavy appearance, with a distinctive, robust muzzle. Young blue wildebeest are born tawny brown, and begin to take on their adult colouration at the age of 2 months. The adults’ hues range from a deep slate or bluish gray to light gray or even grayish brown. Both sexes possess a pair of large curved horns. In the males, the horns can be 83 cm (33 in) long, while the horns of the females are 30–40 cm (12–16 in) long.
The blue wildebeest exhibits sexual dimorphism, with males being larger and darker than females. The blue wildebeest is typically 170–240 cm (67–94 in) in head-and-body length. The average height of the species is 115–145 cm (45–57 in). While males weigh up to 290 kg (640 lb), females seldom exceed 260 kg (570 lb). A characteristic feature is the long, black tail, which is around 60–100 cm (24–39 in) in length. All features and markings of this species are bilaterally symmetrical for both sexes. The average life span is 20 years in the wild, and 21 years in captivity.
The blue wildebeest is mostly active during the morning and the late afternoon, with the hottest hours of the day being spent in rest. These extremely agile and wary animals can run at speeds up to 80 km/h (50 mph), waving their tails and tossing their heads.
The wildebeest usually rest close to others of their kind and move about in loose aggregations. Males form bachelor herds, and these can be distinguished from juvenile groups by the lower amount of activity and the spacing between the animals.
