The shaggy, coarse coat is reddish brown to grizzled grey in colour, darkening with age. Facial markings are composed of a white muzzle, lighter eyebrows and insides of the ears, while there is a cream-coloured ‘bib’ on the throat. The most conspicuous feature of this antelope is a large white ‘halo’ or hollow ring which surrounds the base of the tail on the rump.
The body is heavyset, and the strong legs are black in colour. The heavily ridged horns are found only in males and sweep in an arc backwards and upwards, with the tips pointing forwards. They grow 55-100 cm / 1.6-3.3 feet long.
As it name would suggest, the waterbuck is a good swimmer and flees into water if pursued, although it is reported that they do not actually like going into water.
Waterbuck are rather sedentary in nature. A gregarious animal, the waterbuck may form herds consisting of six to 30 individuals. These groups are either nursery herds with females and their offspring or bachelor herds. At 7-9 months, males are driven from their maternal family and join up with a bachelor herd. These groups have a distinct social hierarchy based on size and strength, and contests are frequent. Males start showing territorial behaviour from the age of five years, but are most dominant from the age of six to nine.
These territories are maintained throughout the year, and a male is generally overthrown before he reaches 10 years of age. Only about 5-10 % of mature males are territorial at the same time. Female groups wander over a home range of 200-600 hectares, which may be kept for up to 8 years and encompasses several male territories.
The waterbuck can not tolerate dehydration in hot weather, and thus inhabits areas close to sources of water.