The waterbuck (Kobus ellipsiprymnus) is a large antelope found in sub-Saharan Africa. It was first described by Irish naturalist William Ogilby in 1833. The waterbuck is predominantly a grazer and is mostly found on grassland.
The waterbuck is the largest amongst the six species of Kobus and is one of the heaviest antelopes. It has a robust build. The shaggy coat is reddish brown to grey, and becomes progressively darker with age. Males are darker than females. Though apparently thick, the hair is sparse on the coat. The hair on the neck is, however, long and shaggy. When excited, the skin of the waterbuck secretes a greasy substance with the odor of musk, giving it the name "greasy kob". The odor of this is so unpleasant that it repels predators. This secretion also assists in water-proofing the body when the animal dives into water. The facial features include a white muzzle light eyebrows and lighter insides of the ears. A cream-colored patch (called "bib") is on the throat. Waterbuck have characterized by a long neck and short, strong, black legs. The long, spiral horns curve backward, then forward. Found only on males, the horns range from 55 to 99 cm (22 to 39 in) in length. To some extent, the length of the horns is related to the bull's age.
Waterbuck are native to southern and eastern Africa (including countries such as Angola, Botswana, The Democratic Republic of Congo, Ethiopia, Kenya, Namibia, South Africa, Tanzania, and Uganda) besides a few countries of western and northern Africa such as Chad, Côte d'Ivoire, Ghana, Mali, Niger, Nigeria, and Senegal. These antelopes inhabit riverine forests, scrub and savanna areas alongside rivers, lakes, and valleys.
Waterbuck are sedentary in nature, however, they may migrate with the onset of monsoon. They are gregarious animals that form herds consisting of 6 to 30 individuals. The various groups are the nursery herds, bachelor herds, and territorial males. As soon as young males start developing horns (at around 7-9 months of age), they are chased out of the herd by territorial bulls. These males then form bachelor herds and may roam in female home ranges. A few females may form spinster herds. Though females are seldom aggressive, minor tension may arise in herds. Waterbuck usually feed in the morning and at night. They are typically silent animals but will use alarm snorts for vocal communication. Waterbuck are excellent swimmers and often enter the water to escape from predators; however, it has been observed that they do not particularly like being in the water. They may also run into cover when alarmed, and males often attack predators.
Waterbuck are herbivores (graminivores). They feed on a variety of grasses and may occasionally browse leaves from certain trees and bushes.
Waterbuck are polygynous breeders; this means that one male mates with more than one female. The breeding season of these antelopes varies with location. In equatorial regions, it takes place throughout the year, and births are at their peak in the rainy season. However, in Sudan (south of Sahara), the mating season usually lasts four months. In some areas of southern Africa, the breeding season extends for even longer periods. The gestational period lasts for 7 to 8 months, followed by the birth of a single calf. Twins are rare. Pregnant females isolate themselves in thickets as parturition approaches. Newborn calves can stand on their feet within a half-hour of birth. They are kept hidden from 2 to 3 weeks up to 2 months. At about 3 to 4 weeks, the calf begins following its mother, who signals it to do so by raising her tail. Though bereft of horns, mothers will fiercely defend their offspring from predators. Calves are weaned at 8 months of age, following which time they join groups of calves of their own age. Young females remain with their mothers in nursery herds, or may also join bachelor herds. While males become reproductively mature at the age of 6 years, females reach maturity within 2-3 years of age.
Waterbuck populations are eliminated from many areas within their large range because of poaching and human settlements. The population decrease in the Lake Nakuru National Park has been attributed to heavy metal poisoning. In some regions, these antelopes are also forced to compete with cattle for grazing.
According to the IUCN Red List, the total Waterbuck population size is around 200,000 individuals. Currently, this species is classified as Least Concern (LC) on the IUCN Red List but its numbers today are decreasing.