The lowland nyala or simply nyala (Tragelaphus angasii), is a spiral-horned antelope native to Southern Africa. It is a species of the family Bovidae and genus Nyala, also considered to be in the genus Tragelaphus. It was first described in 1849 by George French Angas. The body length is 135–195 cm (53–77 in), and it weighs 55–140 kg (121–309 lb). The coat is rusty or rufous brown in females and juveniles, but grows a dark brown or slate grey, often tinged with blue, in adult males. Females and young males have ten or more white stripes on their sides. Only males have horns, 60–83 cm (24–33 in) long and yellow-tipped. It exhibits the highest sexual dimorphism among the spiral-horned antelopes.
The nyala is mainly active in the early morning and the late afternoon. It generally browses during the day if temperatures are 20–30 °C (68–86 °F) and during the night in the rainy season. As a herbivore, the nyala feeds upon foliage, fruits and grasses, with sufficient fresh water. A shy animal, it prefers water holes rather than open spaces. The nyala does not show signs of territoriality, and individuals areas can overlap each others. They are very cautious creatures. Old males live alone, but single sex or mixed family groups of up to 10 individuals can be found. These inhabit thickets within dense and dry savanna woodlands. The main predators of the nyala are lion, leopard and Cape hunting dog, while baboons and raptorial birds hunt for the juveniles. Mating peaks during spring and autumn. Males and females are sexually mature at 18 and 11–12 months of age respectively, though they are socially immature until five years old. After a gestational period of seven months, a single calf is born.
The nyala’s range includes Malawi, Mozambique, South Africa, Swaziland, and Zimbabwe. It has been introduced to Botswana and Namibia, and reintroduced to Swaziland, where it had been extinct since the 1950s. Its population is stable and it has been listed as of Least Concern by the International Union for Conservation of Nature (IUCN). The principal threats to the species are poaching and habitat loss resulting from human settlement. The males are highly prized as game animals in Africa.(from wikipedia)