Damaliscus jimela (Matschie, 1892)

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 : 659-660

160.

Serengeti Topi

Damaliscus jimela

French: Topi du Serengeti / German: Serengeti-Topi / Spanish: Topi del Serengueti

Taxonomy. Damalis jimela Matschie, 1892 ,

Unyamwesi, south-east of Lake Victoria, Tanzania.

Formerly considered a subspecies of D. korrigum . Monotypic.

Distribution. Restricted to the Serengeti-Mara ecosystem in S Kenya and N Tanzania.

Descriptive notes. Few measurements available. Shoulder height 104-126 cm (males) and 105-118 cm (females); weight 111-147 kg (males) and 90-130 kg (females). Slightly smaller than the Uganda Topi (D. ugandae) and the Ruaha Topi (D. eurus). The color is not unlike the Coastal Topi (D. topi), but the purplish shoulder patches are larger, and both shoulder and haunch patches are more clearly set off from the body color. The horns are shorter and less robust than in other species, with not very divergenttips; the skull is relatively narrow. The preorbital glands are naked and prominent in both sexes, and their secretion is colorless. The Serengeti Topi is clearly distinct from its northern relatives, the Korrigum ( D. korrigum ) and the Tiang (D. tiang); it has shorter, less robust horns, with much less divergent tips, and the skull is smaller, with a shorter palate, and is slightly narrower across the zygomatic arches. Compared to the other inland East African species, the extinct Uasin Gishu Topi (D. seloust), the Uganda Topi, and the Ruaha Topi, the skull is somewhat smaller and is noticeably narrower, but with broad nasal bones, and the horns are very much shorter, more slender, and less divergent.

Habitat. Lives in edaphic grasslands, from wide treeless plains to lightly wooded bush and tree savanna, preferring habitat with medium-length grasses, up to knee height. The Serengeti Topi are abundant where green pastures persist through the dry season, especially around lakes and on floodplains. They frequent areas with termite mounds, which are used by males, females, and young to survey the area.

Food and Feeding. Food is almost entirely green grass; the topi’s long narrow snout and mobile lips enable it to select green blades and avoid mature leaves and stems. They do not graze in very short grass areas and very mature pastures. Food intake is relatively high, and they seem slightly less efficient and less selective than hartebeest. Stable isotope analysis of dental enamel confirms a 100% grass diet.

Breeding. The breeding system in this species is one of leks. The Serengeti Topi has not only “classical leks” but also “exploded leks,” in which the degree of aggregation is less spectacular than in the classical case. A territory within the lek will be owned by a male for a year or more, and females move through it in a herd. Larger males tend to be the owners of the territories toward the center of the lek, and estrous females have a marked preference for mating with central males; in the central areas of the lek, females compete fiercely with each other for matings, and dominant females attempt to drive off subordinate ones and interfere with their matings. Like most topi, the male displays to the female with a rocking, high-stepping canter, with his ears pointing downward; this high stepping seems to emphasise the contrast between the purpletoned upper legs and shoulders and the pale lower legs. The gait slows as he approaches the female, with his tail raised; he lifts each foreleg exaggeratedly at the carpus with each stride. There is no urine-testing as such, but the male sniffs the female’s rear end and bleats, and the female rapidly wags her tail and runs a short distance. The male follows her in low-stretch posture, bleating all the while; when she stops, he stops, and he lifts his head up, walks forward and mounts. Breeding is seasonal; calving occurs at the end of the dry season. Calves remain hidden,at least at night. Calves become independent by a year of age, and sometimes as soon as eight months. The males then join a bachelor herd, which may also contain year-old females. Females usually reach adult size in their second year, then start to breed. Males do not reach their adult weight until the third year, and do not become territorial until at least four years.

Activity patterns. Serengeti Topi feed in the morning until 08:00-09:00 h, and in the afternoon from about 16:00 h until dusk. In the dry season, they drink sporadically during the day. Females usually travel along the margins of the males’ territories, even though predators may lurk in these areas. In resting, they may lie on the ground with the muzzle supporting the head, or, especially in male groups, stand in parallel rows, nodding to one another. Preorbital-gland marking, and, especially, ground-horning and mud-packing, occur in both sexes; a grass stem is inserted into the preorbital gland and jiggled to cover it with secretion, then the stem is wiped on the forehead and horns, transferring the secretion to them. In mud-packing, mud and soil are rubbed on the horns and then smeared on the back and chest. The horns become heavily caked with mud after rain. Males, especially, are alertfor trespassers (detected by surveying from their termite mounds), and warn others with snorts, and they threaten and even chase jackals and hyenas.

Movements, Home range and Social organization. In patches of grasslands in woodland habitat, the Serengeti Topilives in sedentary-dispersed mode. The males’ territory size is 0-5— 4 km? and may or may not have common borders; females may stay within a male’s territory for as long as three years, so the territorial male in essence has a harem. The females try to prevent outsiders from entering the territory and becoming part of the harem, although a few outside females may sometimes succeed in joining it. Harem males are vigilant on behalf of females and young, and may threaten predators that come too close. When the dominant bull is absent from the territory, the dominant female may make a high-stepping display to try to intimidate potential invaders. Termite mounds are used by territorial males to advertise and by females and young for surveillance.

Status and Conservation. Classified as Least Concern on The IUCN Red List (as D. lunatus jimela). There are some 55,000 in the Serengeti National Park and 33,000 in its Kenya extension, the Masai Mara National Reserve.

Bibliography. Estes (1991a, 1991b), Kingdon (1982), Murray (1993), Roosevelt & Heller (1914).

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. Restricted to the Serengeti-Mara ecosystem in S Kenya and N Tanzania .