Dwarf Antelopes

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Dwarf Antelopes

These small antelopes belong to the subfamily Neotraginae of the ruminant family Bovidae. A total of 13 species are classified together in the subfamily Neotraginae, including the dik-diks, grysboks, steen-bok, and other dwarf antelopes. Dwarf antelopes range from extremely small (3.3-4.4 lb or 1.5-2 kg) hare-sized royal antelope (Neotragus pygmaeus ) and dik-diks (Madoqua spp.) to the medium-sized oribi (Ourebia ourebi ) and beira (Dorcatragus megalotis weighing from 30-50 lb (10-25 kg). Dwarf antelopes engage in territorial scent marking and possess highly developed scent glands. They are browsers, consuming a diet of young green leaves, fruit, and buds. Dwarf antelopes are also usually not dependent upon regular supplies of drinking water for their survival.

The food of the herbivorous dwarf antelope is digested by means of the four-chambered ruminant stomach. Dwarf antelopes browse or graze, consuming vegetation that is nutritionally rich. They lightly chew their food as they tear leaves from branches. After the food is swallowed, it enters the rumen of the stomach. Digestion is then aided by the process of bacteria breaking down nutrients. The food pulp is then regurgitated and chewed as cud to further break down the food before being swallowed and digested more completely.

Habitat

Dwarf antelopes are found in various terrains throughout the sub-Saharan regions of Africa. The klipspringer (Oreotragus oreotragus ) is found in rocky areas in eastern and southern Africa. Four species of dik-diks are found in dry bush country in the Horn of Africa, that is, Somalia and Ethiopia, as is the beira. Oribis are found in the savanna country, from West to East Africa and in parts of southern Africa.

Steenbok (Raphicerus campestris ) inhabit bushy plains or lightly wooded areas in southern Africa, while the two species of grysbok (R. melanotis and R. sharpei ) are found in stony, hilly areas and scrubby flat country in east-central Africa and the extreme south of the continent. The royal antelope is found in dense forests in West Africa, and Bates’ pygmy antelope (Neotragus batesi ) is found in the forests of the Zaire. Sunis (N. moschatus ) live in forests along the southeastern edge of Africa.

Characteristics

The horns of dwarf antelopes are short, straight spikes found only in the males, although klipspringer females sometimes have horns. Colorations are usually pale, varying from yellow to gray or brown with a white rump patch, while the steenbok is brick-colored. All dwarf antelopes have well-developed scent glands, particularly preorbital glands which can be easily seen on most species as dark slits beneath the eyes. Dwarf antelopes generally have narrow muzzles, prominent ears, and their nostrils are either hairy or bare.

Dwarf antelopes are territorial and many are in lifetime monogamous relationships. They tend to be solitary even though a mated pair shares the same territory. Territories can range in size from several hundred square feet to tens of acres depending upon the nature of the territory and the density of the group’s population. Some monogamous pairs may have a second female, usually a female offspring that has not left the parental territory. Some dwarf antelope males may have two or more females within a small territory.

Scenting behavior among dwarf antelopes maintains the mating bond and protects the territory from

KEY TERMS

Monogamy— Mating relationship where a male and female tend to become permanently paired.

Preorbital scent glands— Glands located below the eyes that are used to mark territory.

Scent-mark— To spread urine, feces, or special fluid from a body gland along a trail to let competitive animals know that the territory is taken.

intruders. Males mark their territory with the scent glands found under their eyes (preorbital glands), and on their hooves (pedal glands). They can mark both the ground of their territory, as well as branches and bushes. Additionally, males will scent their mates, which strengthens the ties between them. Ceremonial behavior in dunging is also seen. A pair will follow one another and deposit urine and feces on the same pile.

Males can be aggressive in defending their territories. They have been known to use their sharp horns to wound intruders. Usually, however, male rivals for females will more often only display aggressive behavior to one another before one retreats. The display of aggressive behavior can include pawing the ground, horning, alarm calls, chasing, and pretending to attack.

Parenting

Dwarf antelope females give birth to one offspring at a time, coinciding with seasonal rains. The gestation period is around six months, depending on the species. Infants hide in the grass for several weeks and the mother returns to feed them twice a day. As the fawn grows, it begins to follow the mother. Young females mature by the age of 6-10 months, while males reach maturity around 14 months. Somewhere between 9-15 months, young dwarf antelopes leave the territory to establish themselves on their own.

In klipspringer families, the pair are found close together, on the average 12-45 ft (4-15 m) apart, and the male assumes the role of lookout while the female cares for the offspring. The male may even become involved with feeding the young klipspringer.

See also Antelopes and gazelles.