a dispute between two males occurred. Wildebeest compete with domesticated livestock for pasture and are sometimes blamed by farmers for transferring diseases and parasites to their cattle. Breeding and reproduction Wildebeest do not form permanent pair bonds and during the mating season, or rut, the males establish temporary territories and try to attract females into them. These small territories are about , with up to 300 territories per . The males defend these territories from other males while competing for females that are coming into oestrus. The males use grunts and distinctive behaviour to entice females into their territories. Wildebeest usually breed at the end of the rainy season when the animals are well fed and at their peak of fitness. This usually occurs between May and July, and birthing usually takes place between January and March, at the start of the wet season. Wildebeest females breed seasonally and ovulate spontaneously. The estrous cycle is about 23 days and the gestation period lasts 250 to 260 days. The calves weigh about at birth and scramble to their feet within minutes, being able to move with the herd soon afterwards, a fact on which their survival relies. The main predator of the calves is the spotted hyena. The calving peak period lasts for 2–3 weeks, and in small subpopulations and isolated groups, mortality of calves may be as high as 50%. However, in larger aggregations, or small groups living near large herds, mortality rates may be under 20%. Groups of wildebeest females and young live in the small areas established by the male. When groups of wildebeest join, the female to male ratio is higher because the females choose to move to the areas held by a smaller number of males. This female-dominated sex ratio may be due to illegal hunting and human disturbance, with higher male mortality having been attributed to hunting. Threats and conservation The black wildebeest has been classified as a least-concern species by the International Union for Conservation of Nature in the IUCN Red List. The populations of this species are on an increase. Now, more than 18,000 individuals are believed to remain, 7,000 of which are in Namibia, outside their natural range, and where it is farmed. Around 80% of the wildebeest occurs in private areas, while the other 20% is confined in protected areas. Its introduction into Namibia has been a success and numbers have