Damaliscus phillipsi, Harper, 1939

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 : 657

153.

Blesbok

Damaliscus phillipsi

French: Blesbok / German: Blessbock / Spanish: Blesbok

Taxonomy. Damaliscus phillipsi Harper, 1939 ,

(Orange) Free State.

This species is similar in many respects to the Bontebok ( D. pygargus ), and during the second half of the 20" century they were usually classified as two subspecies of the same species. Although they are clearly sister species, they are strongly, and consistently, different. Monotypic.

Distribution. South Africa (Eastern Cape N of the Karroo, E into KwaZulu-Natal and N to the Free State and the Botswana border). Today, Blesboks occur sporadically through this range, mainly on private land, and have been introduced into Zimbabwe, Namibia, and eastern Botswana.

Descriptive notes. Head—body 140-160 cm, tail 30-45 cm, weight 70 kg (males) and 60 kg (females). The Blesbok’s general color is reddish-brown, without the purple gloss of the Bontebok. The face blaze is white, but is usually divided by a brown band between the eyes; the buttock patch is not white, merely paler than the body color; and the white (or pale color) at the base of the tail does not extend onto the back of the rump. There is no pale “saddle”; the white on the underparts is less extensive than in the Bontebok; and the lower segments of the limbs are dark brown. The horns are usually straw-colored on the upper surface of the rings. Skull length is 30.4-32. 8 cm; horn length is 33.5-38. 4 cm (both sexes); and horn span is 29-268 mm (both sexes). Diploid chromosome number is 38; there is a fusion between chromosomes 18 and 24, and one of the chromosome chains has only twelve members instead of 13, which differentiates the karyotype from that of the Western Tsessebe ( D. lunatus ) and the Serengeti Topi (D. jimela).

Habitat. Apparently the grasslands of the Highveld wherever surface water was available. Blesboks were generally associated with the sweetveld, especially in areas with medium length high-quality grasses such as Themeda triandra. During the dry season, they would travel into the sourveld, with its tall grasses, and their fat reserves would decrease until the following rainy season.

Food and Feeding. Blesboks feed almost entirely on grass, especially favoring burnt areas with their rapidly sprouting new grass. The very large rumen retains low-digestible grass for a long period.

Breeding. When males are attempting to herd females, there is a great deal of displaying after a territorial male has chased off an invader. Fights between males can be very serious and result in death. During courtship and herding, the male exhibits the low-stretch display; at the period of highest intensity, his tail is curled over his back. He frequently sniffs a female’s vulva, which she facilitates by raising her tail and waving it rapidly. If she is not receptive, she turns and they circle each other. Gestation is eight months; the calving season lasts one or two months. Calves are followers, not hiders, even though they are less precocious at birth than wildebeest, whose calves are hiders. Females give birth within the herd, and the young associate with their mothers right away. They are weaned at about four months. A female becomes sexually mature at 2-5 years.

Activity patterns. Active in early morning and late evening, and they can remain active and feeding in the middle of the day. When moving to feeding areas or watering points, they go in single file, forming paths. Like Bonteboks, they often stand with their heads toward the sun, their faces close to the ground;it is not known whether they are awake or asleep in this posture.

Movements, Home range and Social organization. Like Bonteboks, there are territorial males, female herds, and bachelor groups. Territories are clustered more tightly than those of Bonteboks, in one population averaging only 2-3 ha in size. Territorial behavior may be year-round or seasonal, butterritories are poorly or notat all defended between the end of one rut and the beginning of the next. Territories are marked with displays, including leaping high in the air, preorbital glandular marking, pawing the ground (thereby depositing foot gland secretions), and dung piles. An apparently unique behavior in this species consists of transferring the preorbital secretion copiously to the base of the horns; the Blesbok wipes its horns across grass stems which it had previously marked. Not only males, but females and even calves do this. The female herds are not associated with specific territorial males, but during the rut they are herded into territories and not allowed to leave if the male can prevent it. After the end of the rut, during the cold dry season, the herds aggregate into larger groups of up to 650. These large aggregations occupy defined home ranges, within which each herd has its own home range.

Status and Conservation. Classified as Least Concern on The IUCN Red List (as D. pygargus phillipsr). In historic times there has always been a 300km gap between the ranges of this species and the Bontebok. The Blesbok was exterminated from much ofits range in the 19" century, and the population was reduced to about 2000, but they have recovered rapidly under protection and have been widely introduced outside their former range. Actual estimated population is greater than 200,000 individuals (numbers stable or increasing), of which the main part occurs on private farms.

Bibliography. Estes (1991a, 1991b), Kumamoto et al. (1996), Skinner & Chimimba (2005).

Figures

152. Bontebok (Damaliscus pygargus), 153. Blesbok (Damaliscus phillipsi), 154. Western Tsessebe (Damaliscus lunatus), 155. Bangweulu Tsessebe (Damaliscus superstes), 156. Korrigum (Damaliscus korrigum), 157. Tiang (Damaliscus tiang), 158. Uganda Top 1 (Damaliscus ugandae), 159. Ruaha Topt (Damaliscus eurus), 160. Serengeti Topi (Damaliscus jimela), 161. Coastal Topt (Damaliscus topr)

Distribution. South Africa (Eastern Cape N of the Karroo, E into KwaZulu-Natal and N to the Free State and the Botswana border). Today, Blesboks occur sporadically through this range, mainly on private land, and have been introduced into Zimbabwe , Namibia , and eastern Botswana .