Kobus leche (Gray, 1850)
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https://doi.org/ 10.5281/zenodo.6512484 |
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DOI |
https://doi.org/10.5281/zenodo.6636838 |
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persistent identifier |
https://treatment.plazi.org/id/03F50713-9973-FFC8-034A-FE2CF70BF62F |
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Conny |
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scientific name |
Kobus leche |
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Red LLechwe
French: Cobe lechwe / German: Litschi-Moorantilope / Spanish: Kob rojo
Taxonomy. Kobus leche Gray, 1850 View in CoL ,
Banks of the river Zoaga, lat. 21°. Restricted by Smithers in 1971 as Boteti River, near Lake Ngami ( Botswana).
K. leche was formerly used as a parent taxon that encompassed all lechwe populations (i.e. leche , anselli , kafuensis, and smithemani) as subspecies. This species is considered monotypic here.
Distribution. Scattered locales in E Angola, E Namibia (Caprivi Strip), N Botswana, and W Zambia. View Figure
Descriptive notes. Head-body 150-175 cm (males) and 134-162 cm (females), tail 35-40 cm, shoulder height 94-112 cm (males) and 87-101 cm (females); weight 88— 135 kg (males) and 52-89 kg (females). The body condition of both sexes is lowest during the hot—dry season. Males are approximately 50% heavier than females and have a large and muscular neck. The pelage of both sexes is rather coarse. Overall color is bright reddish-brown; the dorsum is particularly bright, and the flanks and thighs tend to be paler. The belly and inner surfaces of the legs are white, and a wide white stripe runs from chest to chin on the underside of the neck. The forelegs are marked with a bold black stripe on their front surfaces; similar markings are present on the hindlegs below the hocks. Immediately above the elongated hooves is a broad white band. The tail is slender, with a black terminal tuft. A white ring around each eye and another around the nose and lips constitute the facial markings. Horns are present in males only. Horn length in Botswana averages 55 cm, with a maximum of 66 cm; they are shorter than those of male Kafue Flats Lechwe (K. kafuensis). The horns diverge and extend backward from the skull, growing increasingly parallel and curving upward toward the tips. Dental formulais10/3,C0/1,P 3/3, M 3/3 (x2) = 32.
Habitat. The Red Lechwe inhabits seasonal floodplains and shallow swamps adjacent to open water. The interface between inundated and dry grasslands is the most extensively used habitat: this zone is characterized by short grasses (maximum height c. 20 cm) such as Panicum repens, Cynodon dactylon, and Sporobolus spp., with occasional dense stands of tall grasses and reeds. This species tends to avoid woodlands that fringe the floodplains, and it is rarely found in water deeper than 50 cm. Movement through water is facilitated by a bounding gait where all four feet touch the ground and launch into the air simultaneously. This efficient movement through flooded terrain provides the principal means of escape from predators; low water levels correlate with increased predation by Lions (Panthera leo) and African Wild Dogs (Lycaon pictus). Overall population densities of 0-03—4-78 ind/km? occur in the Caprivi Strip of Namibia. In the Linyanti Swamps of Botswana, densities average 7-12 ind/km?, although in the breeding season, local densities may reach 70-90 ind/km?.
Food and Feeding. Perennial grasses form the principal dietary component. Brachiaria latifolia, Eragrostis rigidior, Setaria sphacelata, Hemarthria altissima, and Eulalia geniculata are preferentially consumed along the Chobe River during December and January. When floodwaters rise and Red Lechwe move to higher ground in May, grasses such as Burnatia enneandra, Sacciolepis africana, Trichoneura grandiglumis, and Acroceras macrum are preferred. As water levels recede and expose new growth on the floodplains in July and August, feeding is concentrated on just two principal species (Brachiaria latifolia and Vossia cuspidata ); at this time, grazing often occurs in shallow water. Panicum repens and Eragrostis inamoena may be intensively grazed where present. Other plants, such as the sedges Vetiveria nigritana and Cyperus spp., are mostly fed upon during December. Consumption of annual grasses is largely restricted to January.
Breeding. Mating in the Linyanti Swamp of northern Botswana is concentrated in the four-month-long rainy season (December-March); the breeding season may extend slightly later (until May) in the Okavango Delta to the south. Territorial males, which defend areas of dryland, attract the majority of estrous females. Preliminary courtship involves the male licking and smelling the female’s anogenital region; receptivity is determined by an inconspicuous performance of flehming after tasting a female's urine stream. Gentle taps of the female’s hindlegs and abdomen with a lifted foreleg (“laufschlag”) are followed by tentative mounting attempts (without an erect penis); if the female responds to these final stages of courtship by standing still, copulation takes place. Gestation is approximately 7-8 months. In Linyanti, most calves are born from August to October; this is correspondingly later in the Okavango Delta, where December—January is the peak birthing season. In both areas, this coincides with the recession of floodwaters and a subsequent flush of grass growth. Litter size is one; weight at birth is approximately 6-5 kg. Infants are usually born in stands of reeds or tall grasses and remain hidden within these areas until approximately two months of age. Nursing occurs during sporadic visits by the mother, especially in the early morning and late afternoon. Each bout of nursing lasts 5-10 minutes, and both scent and bleating vocalizations serve to reinforce the maternal bond. Juveniles are weaned at seven months. Sexual maturity of females is highly dependent on body condition. In the Linyanti population, sexual maturity is delayed until 2-3 years of age; even mature females will not successfully carry a pregnancyif their body weightis not above a certain threshold. Among males, testicular development begins at 1-5 years, although males tend to be at least 4-5 years old before they are able to maintain territories and gain access to mates.
Activity patterns. The temperature-mediating effects of inundated floodplains permit Red Lechwes to be active during the hottest parts of the day when flood levels are high. A bimodal distribution of activity, with peaksjust after sunrise and before sunset, is more evident when water levels are low; a midday rest at these times is often spent in the shade of scattered trees. Resting during high-water periods often occurs on elevated termite mounds, although individuals have also been observed standing in shallow water. Females are generally more active than males, with a noticeable differ ence in the time spent feeding (56% of daily activity vs. 35-40%); this is likely due to the increased energy demands of pregnancy and lactation. While foraging during the day, there is a general dispersal over the floodplain; at night, individuals concentrate on dryland adjacent to water. Behavioral patterns at night have not been well studied, although there is indirect evidence that Red Lechwe may continue to move and forage in the dark.
Movements, Home range and Social organization. The Red Lechwe is generally sedentary, with individuals undertaking short seasonal movements to follow their preferred shoreline habitat as water levels rise and fall. Unlike other lechwe species, the Red Lechwe does not congregate in immense herds; males are often solitary, and females associate together in small groups ofless than ten animals. Mixed-sex herds tend to be larger, with up to 20 individuals; occasional groupings of up to 120 individuals have been recorded in Botswana. Regardless of size, groups form and break up regularly, often within the course of a few hours. This lack of structure is also seen when a threat appears: individuals scatter in all directions rather than responding as a herd. Group sex ratios vary widely; females predominate in large groups during summer (December—January) when males are either territorial or associate in small bachelor groups; group sex ratios approach unity in the winter. The territorial system of K. leche is based on the defense of feeding and resting sites, and thus territories are usually clustered into a “territorial complex” of 15-20 territories along the interface between flooded and dry regions. Where interface habitats are plentiful (in areas with numerous islands and inlets), territoriality declines. Females are often herded by territorial males in an attempt to prevent them from leaving their defended area. Territory sizes are 0-005— 0-06 km?; these areas are occupied year-round, but bachelor males are often tolerated on territories outside of the breeding season, particularly at night. Depending on their condition and the degree of competition, males may maintain the same territory for two weeks to 20 months. Other males entering a defended area are threatened or chased by its occupant. Agonistic interactions are always short (less than five minutes) but show extreme variability in intensity, ranging from a brief pressing together of the horns to intense pushing or twisting with horns locked together.
Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List (as K. leche leche ). Approximately 98,000 Red Lechwe are believed to survive in the wild, the vast majority of which (85%) are found in the Okavango Delta of Botswana. Numbers have been greatly reduced throughout much of the species’ distribution due to unsustainable hunting. Population densities are consistently higher in protect ed areas. The Busanga Plain, part of Kafue National Park, currently supports the largest population of the Red Lechwe in Zambia, where it was proven that Red Lechwes have the potential to rapidly recover with protective measures; the region supported only 140 Red Lechwes in 1951, but the population expanded to 1160 in 1971 and 4500 in 1999 after illegal hunting pressures were controlled. Other populations inhabit the Linyanti Swamps of Botswana and the Caprivi Strip of Namibia.
Bibliography. Chase (2007), East (1999), IUCN/SSC Antelope Specialist Group (2008ad), Lent (1969), Lydekker (1914), Von Richter & Osterberg (1977), Williamson (1990, 1991, 1992, 1993, 1994).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
