Sable Antelope (Hippotragus niger)
Order: Artiodactyla, Family: Bovidae
The sable antelope lives in the southern savannah of Africa from southeastern Kenya, eastern Tanzania, and Mozambique to Angola and southern Zaire, mainly in the Miombo Woodland Zone.
I. GEOGRAPHIC RANGE
II. PHYSICAL CHARACTERISTICS
- The sable antelope lives in the southern savannah of Africa from southeastern Kenya, eastern Tanzania, and Mozambique to Angola and southern Zaire, mainly in the Miombo Woodland Zone.
III. FOOD HABITS
- Mass: 220-238 kg.
- The sable antelope has a powerful, robust build and a thick neck outlined by a vertical mane atop sturdy legs. Males and females are strikingly similar until 3 years old, when males become darker and develop majestic horns.
- Males weigh around 238 kg at a height of 116-142 cm. Females weigh 220 kg and are slightly shorter than males. The horns are massive and more curved in males reaching lengths of 81-165 cm, while females' horns are only 61-102 cm in length.
- Coloration in bulls is black while females and young are chestnut, except in southern populations where females turn brown-black. Most sable antelope have white "eyebrows", a rostrum sectioned into cheek stripes, white belly and rump patch. Young under 2 months typically are light brown and have slight markings.
- Typically, sable antelope are specialized grazers feeding on foliage and herbs, especially those growing on termite mounds. During the dry season they are more apt to browse. One of the reasons for declining antelope numbers could be their very specific feeding pattern. Typically they will feed on grasses, which make up to 90 percent of their diet, at heights of 40-140 mm from the ground, taking only the leaf. In a savannah setting, sable antelope are the last to feed on the new grasses available during the late dry season when food availability is vital. In the paddock setting, where grasses are tall (above 140 mm), feed is high in protein and low in fiber, and sable antelope quickly lose weight. The correlation of neck length, angle of the jaws and selective feeding habits serves to separate sable antelope from other grazers and suggests why they are habitat-limited.
- Water is visited at least every other day and no sable antelope will travel more then 2 miles from a watering hole or river.
- Salt licks are visited periodically and they will chew on bones to get trace essential elements not present in mineral-deficient soil.
- Sable antelope females usually undergo only one estrus cycle per breeding season, which lasts from May to July with a peak mating in June.
- Gestation lasts 8 to 9 months, allowing for birth at the end of rains. Normally one calf is born during the end of the rainy season when long grass is available for cover. The mother stays concealed for the first week of the calf's three-week hiding phase. After the first week, the mother joins a maternal group that the calf will eventually join. Yet, the calf will seek out the mother only for nursing. In fact, the mother-offspring bond is so feeble, even small calves will spend days apart in a divided herd.
- Weaning takes place six months after birth, usually towards the end of the dry season when "sourveld" vegetation is lowest in protein and other nutrients.
- Females start to breed at 2.5 years old and congregate in social groups that are a rank hierarchy based on seniority. Males are subordinate to females until they are bigger. At 3 to 4 years of age males are evicted from female social groups and live in bachelor herds until they reach sexual maturity at 5 years.
- Dominant males defend harems of females and their immediate foraging territory extending 300 to 500 meters out from the herd. These dominant males mate with females in their harem and vigorously defend them against intruding males (see behavior section). Males may drop to their knees and engage in horn wrestling in fights. Fatalities from these fights are rare.
- Sable antelope are both nocturnal and diurnal, although they prefer to feed just until dark because of a high risk of predation at night.
- Most sable antelope will travel roughly a mile a day and even less during the dry season.
- The mating season for sable antelopes occurs during the dry-season when sub-populations congregate on remaining green pastures.
- Herds consist of many females (15-25 members) and young, along with one dominant male. Males set up their territories in the best grazing areas to attract females and only a few dominant males will be able to hold those territories. The dominant male will allow subordinate males to graze in his territory as long as they are submissive and show no interest in females. Males will fight if the territory of a male is challenged, but fights to the death are rare.
- There are a few behavioral differences between males and females. Males make scrape markings by pawing dung sites. Males also engage in herding, chasing and foreleg lifting used by courting males to prod reluctant females.
VII. ECONOMIC IMPORTANCE FOR HUMANS
- Favorable habitat is a mixture of savannah woodlands and grassland. Woodlands consist of fire-resistant, broadleaf deciduous trees scattered over an under story of sparse grasses that are grazed during the rainy season. Dry season feeding grounds are grassland areas that were once flooded, and then burned, subsequently producing new growth. If possible, sable antelopes avoid extensive open lands.
Sable antelope are found in parks all across eastern and southern Africa offering an attraction to the eco-tourism industry. Sable antelope are prized trophy animals to many big-game hunters and some people are willing to spend thousands of dollars to hunt them. However, declining sable antelope numbers calls into question the advisability of hunting them.
Sable antelope have no negative affects on humans.
- The IUCN lists the sable antelope as lower risk and conservation dependent, but declining numbers could lead to a threatened listing in the near future. The subspecies Hippotragus niger variani is listed as endangered due to habitat loss and trophy hunting.
- Studies in the past show that a complex blend of factors such as disease, malnutrition, and habitat quality compounded by inter-specific competition and attempts to manipulate populations have limited sable antelope numbers. Historic data has demonstrated their tendency to be dense in some regions and practically nonexistent in others, even in well-managed national parks