Sable Antelope (Hippotragus Niger)
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Artiodactyla Family: Bovidae
WHAT IT IS The name "sable" refers to the black color of the male's coat. Males are about 9 feet long with a shoulder height of 4 feet. The male weighs about 500 pounds and is 20 percent larger than the female. The male's coat is dark brown to black with white under parts, while the female and young males have rich russet coats. Both males and females have stout, scythe-like ringed horns that grow to a length of 20-60 inches and both have stiff manes. Sable antelopes have large ears, large eyes and a keen sense of hearing, vision and smell.
WHERE IT LIVES Southern Savanna, from southeastern Kenya, eastern Tanzania, and Mozambique to Angola and southern Zaire, mainly in the Miombo Woodland Zone. The giant sable, isolated and vulnerable in central Angola, is one of the most endangered antelopes.
ECOLOGY Preferred habitat combines savanna woodland and grassland; trees (fire- resistant, broad-leafed, and deciduous) widely spaced with understory of sparse grasses utilized in rainy season. Drainage-line and floodplain grasslands that produce new growth after the annual fires keep sable in open during dry season. A grazer/browser eats grasses supplemented by foliage and herbs, especially kinds growing on woodland termite mounds. Goes to water at least every other day and regularly visits salt licks (also chews bones to make up for mineral-deficient soils). ACTIVITY Traveling on average approximately 1/2mi a day, sables are especially sedentary on dry-season pastures, when herds may spend weeks on the same field, leaving only to go to water or seek shade during hottest hours. But periodically herds move several miles and resettle on another pasture. Sables also regularly graze until dark, then move off before settling down to chew the cud, a tactic that makes it harder for predators to spot a herd's resting site and sneak up after dark.
SOCIAL/MATING SYSTEM Herds of 15 to 25 females and young are typical but often represent only part of the residents (typically 30-75 sables in good habitat) sharing a common, exclusive home range of 4 to 10 mi2 (10-25 km2), incorporating territories of 1.5 to 3.5 mi2 (3.9-9 km2) of up to 5 bulls or more. Some herds or subpopulations have separate dry- and wet-season ranges miles apart. The general pattern in all populations is dispersal in small groups during the rains and early dry season, and dry-season concentration in large herds on available green pastures. A female rank hierarchy based on seniority is continually reinforced by aggressive and submissive interactions. Males are subordinate to adult females until they grow bigger; by then obvious male secondary characters make them persona non grata to territorial bulls. Evicted from female society between 3 and 4 years, males live in bachelor herds until mature at 5, or stay alone, if no group is available, keeping out of the way of territorial bulls. Territorial bulls often stay alone, even when a female herd is in residence, patrolling and scent-marking or just hanging out in some shady grove. Though conspicuous in a herd of brown females and young, lone bulls standing still in a clump of trees are easily overlooked.
REPRODUCTION An annual calving season at the end of the rains (except perennial in Kenya's Shimba Hills). Season extends for several months and a few calves are born as much as 6 months out of phase, Gestation 8 to 9 months. Females conceive at 2.5 years; males adolescent by then but unable to compete for territories and mating opportunities until mature. Even in territorial class, certain prime bulls dominate their neighbors. OFFSPRING AND MATERNAL CARE Mothers stay secluded for first week or so of the calf's 3-week hiding stage. Cows with calves concealed in the same locale associate in maternal herds. Calves join cohesive peer group as they outgrow the concealment stage and seek mothers only to nurse; after weaning (6-8 months), calves have still less contact. Maternal-offspring bond is so weak that even small calves may be in different sections of a divided herd for days.
PREDATORS Because it is big and inhabits regions with comparatively little wildlife, sables usually have relatively few predators. Lucky for them, as laggard young are vulnerable to spotted hyenas and leopards.
DIFFERENCES IN SABLE ANTELOPE BEHAVIOR
TERRITORIAL ADVERTISING Scrape marks made by pawing identify deposits made by territorial sable. The only consistent difference between the dunging sites of patrolling sable and roan antelope are differences in track and pellet size. Urine-testing. All sables including calves, test urine.
MALE BEHAVIOR Driving and chasing, roaring. Of sexually interested male. Foreleg-lifting used by courting male to prod lying female into getting up is behavior of persistent bull courting reluctant female.
FEMALE BEHAVIOR Flight, including fear-gaping and screaming when chased hard.
Mother and Offspring A Lone sable antelope emits piercing, birdlike whistles. When Separated mothers, and young search for one another.