Taurotragus oryx (Pallas, 1766)

Don E. Wilson & Russell A. Mittermeier, 2011, Bovidae, Handbook of the Mammals of the World – Volume 2 Hoofed Mammals, Barcelona: Lynx Edicions, pp. 444-779 : 617

39.

Common Eland

Taurotragus oryx

French: Eland du Cap / German: Elenantilope / Spanish: Eland de El Cabo

Other common names: Cape Eland, East African Eland, Livingstone's Eland

Taxonomy. Antilope oryx Pallas, 1766 ,

S Africa.

The two eland species are separated taxonomically from related Strepsiceros species because they have very large supraorbital foramina in very deep, wide, and elongated depressions; mesopterygoid fossa forms a wide U-shape; and ends of the parocciptal processes are short and free. Three subspecies of Common Eland are sometimes recognized, in three distributional areas: the southern oryx , the central pattersonianus, and the north-eastern / livingstonii . Recent morphometric analyses, however, suggest that a few differences, on average only, can be found between populations in southern ( oryx ) and eastern ( livingstonii ) Africa.

Subspecies and Distribution.

T.o.oryxPallas,1766—SAfricaincludingNamibia,Botswana,Swaziland,andSouthAfrica.

T. o. livingstonii Sclater, 1864 — S & E Africa; N limit through Angola and S DR Congo, then N to Rwanda, Uganda, SE Sudan, SW Ethiopia, Kenya, S Somalia, and Tanzania.

Descriptive notes. Head-body 250-340 cm (males) and 200-280 cm (females), tail 54-75 cm, shoulder height 135-183 cm (males) and 125-153 cm (females); weight 400-942 kg (males) and 390-600 kg (females). The Common Eland is rather oxen-like in its body form compared to African antelopes; the chest, neck, and shoulders are massive, particularly in older males; the legs are relative short and sturdy. Males generally weigh 35-50% more than females. Both sexes have spiraled horns, but they are longer, thinner, and less spiraled on females (51-70 cm) than on males (43-67 cm). Both sexes have a dewlap with a terminal tuft of hair on the throat, but it does not go up to the chin as it does on the Giant Eland (7. derbianus ). The dewlaps of old males become particularly long and vary enough in shape and character that an individual can be identified in the field. Only males develop a dark crest of tufted hair on their foreheads and noses (nasal brush), possibly associated with apocrine glands. Coat patterning is more pronounced in northern populations. The pelage is nearly uniform in color throughout the body and ranges from red-brown (young) to dark gray; males tend to turn blue-gray (referred to as “gray males”) as they age and have a darker neck, as their dark skin shows through thinning hairs. The Common Eland has a dark dorsal crest, small mane, and 2-12 lateral transverse stripes that are more prominent anteriorly. Individuals in the southern part of the range have a paler pelage, and the stripes are paler or nearly absent. The legs have white markings and black “garters” around the upper forelegs and around the large hooves; the front hooves are larger than the hindhooves, to support the concentration of weight in the front. The mouth and teeth of Common Elands are disproportionately small relative to overall mass, which reflect its selective diet. The ears are pointed and small, and the cheeks are not spotted like on the Giant Eland. The tail is long and tufted black on the end. Dental formula is I 0/3,C0/1,P3/3, M 3/3 (x2) = 32. Diploid numbers for the Common Eland are 31 for males and 32 for females—among the lowest of the Tragelaphini .

Habitat. The Common Eland is considered one of the most adaptable African ungulates and uses a variety of habitats, some arid to subdesert and most with unpredictable food availability. It can be found at elevations up to 4600 m. It occurs most commonly in open woodlands, brushy Acacia savannas, open grasslands, and associated habitat mosaics, and avoids thick forests, swamps, true deserts, and completely open grasslands. It will use cropland if available. Free water is not a critical habitat component. The great size of the Common Eland permits considerable heat storage and water conservation, and it does not congregate around water sources like many African ungulates.

Food and Feeding. Herbivorous, classified variously as a browser or intermediate feeder, but definitely selective given its small mouth size. Throughout the year, Common Elands are predominately browsers, selecting leaves, fruits, and pods of a variety of woody and herbaceous species. Leaves and fruits of common trees and shrubs in its preferred habitats, and thus in its diet, include Acacia, Combretum, Grewia, Rhus, and Ziziphus. Common Elands also will eat considerable amounts of grasses (Setaria and Themeda), but only when growth is most succulent, for example, at the beginning of the wet season. The Common Eland usesits horns to pull down branches and dig for tubers.

Breeding. Mating and births occur throughout the year, but peaks in births are noted late in the dry season and early in the rainy season. Males engage in lateral displays, sparring with horns, neck-wrestling (also common among juvenile males), head-shaking displays, and low-head posturing, but most observers have noted that male-to-male interactions are “low-keyed.” Well-developed secondary sexual characteristics of male Common Elands and their displays to one another allow males to assess competitors’ potential quite accurately and avoid direct confrontation. Dewlap size and the castanet-like knee-clicking of males (audible for about 100 m) are associated with age and body size. Gray males regularly adorn their nasal brushes and horns with wet, often urine-soaked soil and vegetation. Real combat does occur between fully mature males, but it is brief. Mature dominant males do most of the breeding by seeking and closely tending estrous females. Urine testing and subsequentlip curling are commonly performed by all sexes and ages (beginning as early as three months of age). While tending a female, a male follows her closely and stimulates her to urinate by nosing and licking her genitals, rests his chin on her hindquarters, and attempts to mount. A male often approaches a female in a low-stretch posture while rapidly flicking his tongue and salivating profusely. If not immediately receptive, females may appear aggressive by responding with horn swiping, ritualized biting, and mock attacks. If the female stops and appears receptive, the male assumes an erect posture and bleats submissively like a calf. Length of the estrous cycle is 21 days, copulation is brief (roughly four seconds), and gestation is 8-9 months. Gravid females seek a secluded place to give birth, usually in a lying position. Newborn Common Elands weigh about 25-30 kg, stand soon after birth, mimic their mothers’ feeding behavior, and are weaned at about six months. Newborns join nursery groups within a few days of birth,if available; otherwise, they remain alone and hidden for up to two weeks. Neonates only go to their mother to nurse if she calls. Females engage in communal defense of young, but otherwise they are rather disinterested parents. The young grow rapidly and can be more than 450 kg at one year of age. Young and juvenile Common Elands spend a lot of time together and become independent early in life. Average longevity is 15-20 years, longer in captivity; mortality is most affected by food supply, but predation of young by Lions and hyenas can be high.

Activity patterns. Daily activity patterns of the Common Eland are variable by season and location and are most dependent on forage availability and temperature. In very hot weather, they may rest in the shade all day to minimize heat gain and forage throughout the night. In cooler weather, a typical pattern is alternating two-hour bouts of feeding and resting/ruminating, starting at 06:00 h and lasting throughout the day and even well into the night, until 02:00 h if forage availability is low. Introduced Common Elands in South Africa display different seasonal patterns of activity, with two phases of feeding and resting/ruminating during the day in winter and two phases of feeding, but only one of resting/ruminating, during the day in summer.

Movements, Home range and Social organization. The Common Eland is nomadic, traversing non-exclusive large home ranges in search of the best foraging opportunities. Generally, mature males are more sedentary than females and juveniles of both sexes. Male home ranges were 6-71 km? and female home ranges were 34-360 km? in Nairobi National Park, Kenya. Densities are commonly less than 1 ind/km?, often much less, but surveying the Common Eland is difficult. Given their bulk, these animals are relatively slow, but they can maintain a trot at speeds of 35 km /h for several kilometers. Young individuals are remarkable jumpers and can clear 3m barriers from a standing position. Common Elands are gregarious and can occur in herds of 100-500 individuals (particularly when food is abundant), but group sizes and membership change regularly. Groups may be of mixed sexes and ages, female-only, male-only, and entirely young-of-the-year and juveniles. The only regular association is between a female and her offspring, but even that relationship is ephemeral because of the tendency of young Common Elands to prefer their own company over adults. It is not uncommon to find groups of young and juveniles, numbering two to more than 400, completely disjunct from adults. Males are less sociable than females: typically, there are 3-5 males/group and 10-12 mostly females/mixed group. Females have been shown to maintain a complex, and generally linear, dominance hierarchy in captivity; their relationships in the wild may have similar characteristics but are no doubt more fluid. Fully mature males tend to associate with males of smaller stature or occur alone.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The total Common Eland population was estimated at 136,000 in the late 1990s, and it is considered stable range-wide, with some populations decreasing. Extinct in Burundi. About 50% of the extant Common Elands occur in protected areas, with another 30% on private ranches. It is a popular trophy animal, and the meat is prized, so poaching can be a significant localized problem. Because of the economic value of their high-quality meat and milk, Common Elands are, or have been, semi-domesticated in Kenya, South Africa, Zimbabwe, Russia, Ukraine, Great Britain, and the USA. Habitat loss due to an expanding human population has reduced the historical range of Common Elands by about 50% and represents the mostsignificant ongoing threat to their conservation.

Bibliography. Bro-Jorgensen & Dabelsteen (2008), Cerling et al. (2003), Dolly & Shurter (2010), East (1999), Estes (1991a, 1991b), Hillman (1974, 1979), Hofmann & Stewart (1972), IUCN/SSC Antelope Specialist Group (2008bj), Jeffrey & Hanks (1981), Kiley-Worthington (1978), Kingdon (1982, 1997), Leuthold (1977), Lydekker & Blaine (1914), McNaughton & Georgiadis (1986), Nowak (1999), Pappas (2002), Pennington (2007), Rowe-Rowe (1983), Rubes et al. (2008), Skinner & Chimimba (2005), Spencer (1995), Spinage (1986), Sponheimer et al. (2003), Taylor (1969, 1970), Underwood (1979, 1981), Walther (1990c), Weigl (2005), Wirtu et al. (2004).

Figures

On following pages: 35. Cape Kudu (Strepsiceros strepsiceros); 36. Zambezi Kudu (Strepsiceros zambesiensis); 37. Northern Kudu (Strepsiceros chora); 38. Western Kudu (Strepsiceros cotton); 39. Common Eland (Taurotragus oryx); 40. Giant Eland (Taurotragus derbianus).

Subspecies and Distribution. T.o.oryxPallas,1766—SAfricaincludingNamibia,Botswana,Swaziland,andSouthAfrica. T. o. livingstonii Sclater, 1864 — S & E Africa; N limit through Angola and S DR Congo , then N to Rwanda , Uganda , SE Sudan , SW Ethiopia , Kenya , S Somalia , and Tanzania .