Duikers

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Duikers

Duikers are small African antelopes in the subfamily Cephalophinae of the large family of Bovidae. This family of hoofed animals includes antelope, gazelles, cattle, sheep, and goats. Like all bovids, duikers have even-toed hooves, horns, and a four-chambered stomach structure that allows them to digest a diet of plants. Duikers are found throughout sub-Saharan Africa. These small antelopes range in size from 22 in (55 cm) to as much as 57 in (1.45 m) in length, and weigh from as little as 9 lb (6 kg) to as much as 176 lb (80 kg).

There are 17 species of forest-dwelling duikers (Cephalophus ). These are the blue, yellow-backed, bay, Maxwell’s, Jentink’s, black-fronted, red-flanked, Abbot’s, banded or zebra, black, red, Ader’s, Peter’s, Harvey’s or Zanzibar duiker, black-striped, Gabon or white-bellied, and Ogilby’s duiker. There is only one species of savanna duiker, the bush or gray duiker (Sylvicapra grimmia ), which is found in thin forest and savanna woodlands. Duikers are heavily hunted for their meat, and many of the forest species are threatened or endangered.

Adaptation

Duikers have not been studied to any great extent in the wild because they live in dense rainforest habitats and are difficult to observe. They are, nonetheless, much sought after for their meat. The number of species of duikers increases with the size of the rainforests they inhabit.

The word duiker is an Afrikaans word that means “divers” or “those that duck.” When duikers are alarmed they dive for cover into thickets. The front legs of duikers are shorter than the powerful hind legs. Duikers have a relatively big head, with a wide mouth, small ears, short backward-slanting horns, and a crest of erect hair on the forehead. Female duikers are on average a little larger than males and also possess horns.

Most duikers are nocturnal, remaining sedentary during the daylight hours. They are browsers, animals that eat the tender shoots, twigs, and leaves of bushy plants, rather than grazing on grass. Some species of duikers also eat buds, seeds, bark, and fruit, and even small rodents and birds. The moisture content of leaves is usually sufficient to satisfy their water needs during the rainy season, when duikers do not drink. Duikers are preyed upon by leopards, large predatory birds, and even baboons.

Social life

Duikers are not social animals and are usually seen alone or in pairs. Like other small browsing antelopes, duikers are territorial and monogamous (they mate for life). The size of the territory of a pair of duikers is between 5-10 acres (2-4 ha), and both sexes defend it from intrusion by other members of their species.

The care of the young is done mainly by the females. The first-born offspring leaves its parents before a younger sibling is born. Within the territory, the male and female duikers rest and feed at different times, and often wander away from one another, which may be why they are seen alone so often.

The courtship ceremony of duikers includes close following of the female by the male, circling and turning by the female, hiding, moaning and snorting by both, mutual scenting, and then mating. Females usually give birth to one offspring at a time. The gestation period varies from as little as four months to as long as nine months. The newborn duiker lies concealed for the first few weeks of its life when it is nursed by its mother.

Male duikers have scent glands underneath their eyes and on their hooves. The glands under their eyes extend downward and secrete through a series of pores rather than through one opening, as in other antelopes. Duikers in captivity have been seen to mark their

KEY TERMS

Bovidae (Bovids)— A family of animals characterized by having even-toed hooves, horns, and a four-chambered stomach and by chewing its cud as part of its digestive process.

Browsers— Mammals that feed primarily on leaves of plants, as opposed to grazing on grass.

Diurnal— Refers to animals that are mainly active in the daylight hours.

Facultative monogamy— Among pairs of mated animals where the care of the young is left primarily to the female member and the offspring leaves the parents before the next sibling is born.

Nocturnal— Animals that are mainly active in the nighttime.

Savanna— A treeless plain of high grasses found in tropical climates.

territory as frequently as six times within ten minutes. Male duikers also use their scent glands to mark their opponents in battle, as well as engaging in mutual marking with their mates and their offspring.

Because duikers are nocturnal and elusive animals, their populations sizes are hard to estimate. Most species are threatened to some degree by habitat loss and hunting. The IUCN considers Ader’s duiker (Cephalophus adersi ) to be critically endangered, with only about 640 animals remaining in Zanzibar and a much smaller number in Kenya.