The Blue Wildebeest (Connochaetes taurinus), also called the common wildebeest, white-bearded wildebeest, brindled gnu, or blue gnu, is a species of antelope native to Eastern and Southern Africa. The blue wildebeest is one of the two species of wildebeest. It is placed in the genus Connochaetes and family Bovidae, and has a close taxonomic relationship with the black wildebeest. The blue wildebeest is known to have five subspecies. Blue wildebeest typically weigh roughly 300 to 600 pounds; males are larger and darker-colored than females. They are social animals living in large herds. Each year they merge herds and migrate from the savannas of Kenya to the Serengeti National Park in Tanzania. When they get to Tanzania, they mate, have their babies, and graze across the plains. Along the journey, they have to face many hardships such as predators. These include lions, hyenas, African leopards, cheetahs, Nile crocodiles, and African wild dogs, with jackals preying on the young. But they have lots of eyes on the lookout and while lots of them are grazing, some are on high alert, sensing for danger. Plains zebras, kudus, impala, and Thomson's gazelles will migrate with them and keep a lookout, too. Each year, the males battle each other for a harem of females to mate with; they get down on their knees and joust at each other. Blue wildebeest have an estimated population of around 1.5 million, most of which are in the Serengeti.