Raphicerus campestris [Thunberg, 1811].

Citation: Mem. Acad. Imp. Sci. St. Petersbourg, 3:313.

Type locality: South Africa, Cape of Good Hope.

The taxonomic record (above) is provided by Wilson and Reeder (1993). Over 24 subspecies of the steenbok have been named, although their validity is questionable. There are, however, two widely-accepted subspecies groups: R. c. campestris from southern Africa and R. c. neumanni from east Africa (Kingdon, 1997). Synonyms for Raphicerus campestris include acuticornis, bourquii, capensis, capricornis, cunenensis, fulvorubescens, grayi, hoamibensis, horstockii, ibex, kelleni, natalensis, neumanni, pallida, pediotragus, rupestris, steinhardti, stigmatus, subulata, tragulus, ugabensis, zukowskyi, and zuluensis (Wilson and Reeder, 1993).

Steenbok, like all dwarf antelope, are petite animals, weighing 7-16 kg and measuring 70-95 cm in length. Steenbok carry their heads high and have long legs (in contrast to the crouched stance of small forest antelope such as Neotragus or Cephalophus), with a shoulder height between 45 and 60 cm.

Steenbok have rather coarse pale brown hair, with regional variation from fawn to bright reddish-brown or even gray over the upper parts (Nowak, 1991; Kingdon, 1997). The underside of the body, including the insides of the legs and underside of the tail is white (Nowak, 1991). The pelage is very uniform in color, with a crisp interface between the brown upper body and white underparts. The haunches of the steenbok are rounded, although the back is relatively flat (Kingdon, 1997). The tail is short and thin, and according to Kingdon (1997) it is not readily visible in the field. There are no dewclaws present (Nowak, 1991). The general size, shape, and coloration of the steenbok is similar to the gray duiker (Sylvicapra grimmia) and oribi (Ourebia ourebi), and this antelope may be mistaken for either species in the field (Kingdon, 1997).

Steenbok are renowned for their very large ears, which are covered with white hair on their inside surface (Kingdon, 1997). A black wedge which extends from the rhinarium and tapers towards the forehead constitutes the only major facial marking (Walther, 1990; Kingdon, 1997). The small nose is slightly upturned and naked at the tip (Walther, 1990; Kingdon, 1997). Small preorbital glands are present just in front of the large dark eyes (Walther, 1990; Kingdon, 1997). The eyes themselves are rimmed with black skin, and then surrounded by a ring of white hair (Kingdon, 1997).

Males possess a pair of very upright horns - these are never found in females (Walther, 1990; Kingdon, 1997). The horns are simple spikes which are entirely smooth, lacking ridges over their entire length (Nowak, 1991; Kingdon, 1997). The horns may grow 7-19 cm in length (Walther, 1990).

R. campestris breeds throughout the year, although Walther (1990) also mentions a peak in births in the months of November and December. The gestation period is approximately 170 days, or just over 5.5 months (Walther, 1990; Kingdon, 1997). Although females possess four mammae (teats), there is typically a single young per birth (Walther, 1990). Infants weigh approximately 0.9 kg at birth and are precocious, able to walk within five minutes of being born (Walther, 1990; Kingdon, 1997). Despite this advanced development, steenbok have adopted a "hider" strategy, with the infant remaining well hidden for two weeks before it begins to follow its mother while she forages (Kingdon, 1997).

Infants are weaned at approximately 3 months of age (Walther, 1990; Kingdon, 1997). Sexual maturity is reached at the young age of 6-7 months for females, and after 9 months for males (Walther, 1990; Kingdon, 1997). This early maturity, coupled with the fact that some females will breed twice per year, may explain how this species continues to persist in areas with sustained persecution (Kingdon, 1997). According to Kingdon (1997), the lifespan of the steenbok is at least seven years, while Walther (1990) suggests that this species could live until 10-12 years of age.

Steenbok inhabit savannahs in dry climates, often found in lightly wooded grassland at altitudes from sea level to 4,750 meters (Nowak, 1991; Kingdon, 1997). In South Africa, R. campestris is typically found in more open territory, while East African populations favor stony savannah in Acacia-grassland mosaics (Kingdon, 1997). Kingdon (1997) reports that steenbok are rarely observed in Miombo (Brachystegia) woodland, and tend to favor transitional or unstable conditions created by brush-clearance (either by agriculture, road construction, or elephants). Riverbeds and belts of thicket provide important sources of refuge when steenbok inhabit open habitats (Kingdon, 1997).

Due to their small body size, adult steenbok have many different predators, including leopard, caracal, and pythons (Walther, 1990). In addition, juveniles are depredated by smaller predators like jackals, the Libyan wildcat, ratel, baboons, eagles, and monitor lizards (Walther, 1990).

Steenbok are primarily browsers, feeding at or near ground level. Shoots of most dominant shrub and tree species within their habitat are eaten, including Acacia, leafwood (Combretum), buffalo thorn (Ziziphus), Bridelia, and mopane (Colophospermum) (Kingdon, 1997). Fruits are occasionally consumed, as are sprouts of some grasses during the stages of early growth. Steenbok will also use their sharp hooves to scrape up selected roots and tubers (Kingdon, 1997). Water is not essential; steenbok in the Kalahari subdesert may be found as far as 80 kilometers from a permanent water source (Kingdon, 1997).

Steenbok are largely diurnal, although in hot weather the activity pattern will shift to the cooler hours in the early morning and evening (Walther, 1990; Nowak, 1991). The social system of this small antelope appears to be an independent or solitary existence within a stable pairbond - a pair of steenbok inhabit a territory of 4-100 hectares in size, but only come together for breeding (Walther, 1990; Kingdon, 1997). During the female's estrus period, her partner often becomes quite aggressive (Kingdon, 1997). Observations reported by Kingdon (1997) suggest that while the members of a pair do not interact directly for most of the year, routines and scent marks keep the animals aware of each others movements and positions (Kingdon, 1997). Territories are marked with dung-middens connected by trails, which, through use, become marked with secretions from the pedal glands (Kingdon, 1997). Following defecation, both sexes scrape at the middens, potentially associating their pedal gland scent with the dung pile (Kingdon, 1997).

In the presence of danger, steenbok first hide, crouching with the neck pressed against the ground and ears retracted to avoid detection (Nowak, 1991; Kingdon, 1997). If the threat persists or approaches, the animal will flee, with fast zig-zagging flight interrupted by attempts at concealment by lying down flat (Walther, 1990; Kingdon, 1997). Steenbok will also purportedly seek refuge in aardvark burrows when pressed (Walther, 1990; Nowak, 1991).

Steenbok have a karyotype of 2n = 30 (Wallace & Fairall, 1967).

Africa houses two distinct and disjunct populations of steenbok, the eastern race being found from southern Kenya to central Tanzania, and the southern race which inhabits Angola, western Zambia, Zimbabwe, and southern Mozambique south to South Africa.

Countries: Angola, Botswana, Kenya, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Zambia, and Zimbabwe, regionally extinct in Uganda (IUCN Antelope Specialist Group, 2008).

R. campestris is listed as "Least Concern" on the IUCN Red List (IUCN Antelope Specialist Group, 2008) and is not listed by CITES (2009). The total population of steenbok in Africa is estimated at approximately 663,000 individuals, of which 25% are found within protected regions and an additional 30% found on private lands (East, 1999). However, the IUCN Antelope Specialist Group (2008) suggests that even this number may be an underestimate, noting that populations are stable, with some protected areas experiencing an increase in numbers. Depredation by domestic/feral dogs and hunting of (particularly) juveniles may pose a threat to the species in certain areas, but across their range steenbok have no major threats.

"Steenbok" is actually the Dutch name for ibex (Capra ibex), and despite the lack of resemblance between the two species, the Dutch settlers (Boers) gave this small grassland antelope the same name as the mountain goat they were familiar with from back home (Walther, 1990). Alternatively, it has been suggested that since steen translates as "stone" or "brick", steenbok may refer to the reddish color of the animal. Alternate spellings of the name steenbok include steinbok, steenbuck, and steinbuck. The genus Raphicerus is derived from the Greek words raphis and keras, meaning "needle" and "horn" respectively - a reference to the sharp, straight horns of this genus. Campestris is Latin for level country or a plain, the habitat this species prefers.

Local names

Isha, Dondor [Swahili] (Kingdon, 1997)

 

French

Steenbok (Walther, 1990; Kingdon, 1997)

Raphicère champètre (Walther, 1990)

 

German

Steinböckchen (Walther, 1990; Kingdon, 1997)