Kobus kob occurs in the moist savannah zones of Africa, from Senegal to western Kenya (Nowak 1991).
Biogeographic Regions: ethiopian (Native )
K. k. kob (Buffon’s or Western Kob) has the widest distribution range, from Senegal to Central African Republic and DR Congo. They are now extinct in the Gambia and Sierra Leone and most likely in southern Mauritania.
K. k. thomasi (Uganda Kob) occurs in north-east DR Congo, south-west Sudan and widely throughout Uganda. They once ranged into south-west Kenya, and lakeside areas of north-west Tanzania, but are now extinct there.
K. k. leucotis (White-eared Kob) have the most restricted range of the three subspecies, occcurring in Sudan, south-west Ethiopia and extreme north-east Uganda.
Standing aproximately 92 cm high at the shoulder, Kobus kob has a short, reddish-brown coat, with a white throat-patch and white underparts. A distinctive black stripe marks the front of the forelegs (Stuart and Stuart 1992). Horns average 44 cm in length and are ridged with transverse corrugations. They are curved, turning up at the tips. Only males carry horns (Smith 1985). The multiple subspecies that comprise Kobus kob are distinguished primarily by variation in pelage darkness (Meester and Setzer 1971).
Range mass: 90 to 120 kg.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: ornamentation
- Meester, J., H. Setzer. 1971. Mammals of Africa: an identification manual. Washington, DC: Smithsonian Institution Press.
- Smith, S. 1985. The atlas of Africa's Principal Mammals. San Antonio: Natural History Books.
- Stuart, C., T. Stuart. 1992. Southern, Central, and East African Mammals: A photographic guide. Cape Town, South Africa: Struik Publishers.
Kob are usually found near permanent water sources (Deutsch 1994a). They frequent moist savannah, floodplains, and the margins of adjacent woodlands. Elevated areas with short grass are the preferred habitat for lek sites (Deutsch and Weeks 1992).
Females prefer high-visibility mating sites with short grasses and few thickets. This preference may serve to avoid lion predation (Deutsch and Weeks 1992), though Balmford and Turyaho (1992) disagree.
Terrestrial Biomes: savanna or grassland
Habitat and Ecology
Kob are herbivorous. They eat grasses and reeds, and may migrate great distances to graze along watercourses (Fryxell and Sinclair 1988).
Life History and Behavior
Perception Channels: tactile ; chemical
Status: captivity: 17.0 years.
Lifespan, longevity, and ageing
Kob usually have a lek mating system, in which males defend small territories clustered on traditional mating grounds. Females visit these leks only to breed, and males provide no parental care. This mating system may have evolved because males cannot defend the widely-dispersed food resources or the dynamic and temporary female herds (Deutsch 1994a).
Within a lek, 20 to 200 males defend territories 15 to 200 meters in diameter (Nowak 1991). Male territories are smallest and most highly-contested in the center of the lek, where most matings occur. These territories maintain their popularity among females despite rapid male turnover (Deutsch 1994a). In areas of lower population density, males are spaced farther apart and hold their territories for longer periods of time (Nowak 1991; see below for further discussion of the effects of population density on mating system).
Each lek is associated with a female herd of about 100 individuals. Females begin to mate at the age of one, but males must normally wait for several more years (Nowak 1991). Larger numbers of females associate with larger leks, possibly because females stay on the lek longer when more males and other females are present (Deutsch 1994b).
Females give birth to a single offspring after a gestation period of around 9 months. Calving season may vary with location, but the Boma population of Uganda kob gives birth at the end of the rains, in November-December (Nowak 1991).
Range number of offspring: 1 (low) .
Average number of offspring: 1.
Range gestation period: 7.87 to 8.9 months.
Range weaning age: 6 to 7 months.
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 5405 g.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (male)
Sex: male: 365 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 403 days.
Parental Investment: altricial
Meester and Setzer (1971) report the range of the species as greatly diminished, but kob are still common in national parks (Njiforti 1996). Kob in the Boma grassland ecosystem form the second largest population of antelope in Africa (East 1988).
Muhlenberg and Roth (1985) list a series of management recommendations to maintain kob at their present population levels: (1) grassland habitat near rivers should be left undeveloped for grazing and access to water, (2) hunting should focus on bachelor males rather than the easily-obtained territorial males, and (3) simgle females should not be harvested, as they are likely to be in estrous or caring for young.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
IUCN Red List Assessment
Red List Category
Red List Criteria
Similarly, the population of the White-eared Kob has been estimated at more than 100,000 (East 1999). An aerial survey of part of Southern Sudan carried out by WCS in 2007 produced a population estimate of >753,0000 (Fay et al. 2007).
Numbers of Uganda Kob within parks and reserves may be more stable, with an estimated total population size of 100,000 (East 1999).
Today, Kob live in many isolated populations, most of which are smaller than 1,000 animals. In the late 1990s only two regions in West Africa contained populations of more than 10,000 individuals (in Senegal and Cameroon), while only the Uganda population of K. k. thomasi contained more than 10,000 animals (East 1999).
Kobs can reach high densities when well protected in areas of favourable habitat, ranging from 15-40 animals/km² (Fischer in press; and references therein); however, in areas of heavy hunting pressure, densities decline to less than 1/km² (Fischer 1998). The highest densities of Kob (1,000/km²) have been reported around drinking sites in the dry season (Fryxell 1987).
Loss of habitat to the expansion of settlements, agricultural development and livestock is another major cause of population reduction. For example, the Uganda Kob formerly occurred in south-western Kenya and north-western Tanzania in grasslands alongside Lake Victoria, but was exterminated by the spread of settlement and agricultural development.
Droughts, disruption of the natural flooding regime (e.g. the construction of the Maga dam on the Logone floodplain, Cameroon), and outbreaks of rinderpest have also been cited as significant causes of population decline (East 1999; Fischer in press).
Protected areas important for the survival of Buffon’s Kob, include: Niokolo-Koba (Senegal), Comoe (Côte d’Ivoire), Arly-Singou (Burkina Faso), Mole and Bui (Ghana), Pendjari (Benin), Waza and Benoué and Faro National Parks of the North Province (Cameroon), Zakouma (Chad), and Manovo-Gounda-St. Floris and Sangba (Central African Republic) (East 1999; Fischer in press).
Less than 1% of the total population of White-eared Kob occurs in protected areas, such as the Boma and Badingilo National Parks in south-east Sudan (East 1999). Recent surveys in south-eastern Sudan suggest that, despite the civil war, the white-eared kob populations still survive in good numbers. Further surveys are urgently required to clarify the white-eared kob’s current status and investigate possible conservation actions.
The Uganda kob survives in good numbers in Garamba and Virunga National Parks (DR Congo), and Murchison Falls-Aswa Lolim, Queen Elizabeth and Tore-Semliki (Uganda) (East 1999). The status of this subspecies is likely to improve as the rehabilitation of other areas of Uganda proceeds in the next few years, e.g., Aswa-Lolim and Toro-Semliki, although political disturbances in DR Congo may adversely affect the important populations of Garamba and Virunga National Parks.
A few Uganda Kob are held in captivity (East 1999).
Relevance to Humans and Ecosystems
No negative effects are described in the literature
Kob are commonly hunted for sport and food. A survey of bushmeat preferences in Cameroon ranked kob as the third most favored species, second only to North African porcupine and guinea fowl (Njiforti 1996).
Positive Impacts: food
The kob (Kobus kob) is an antelope found across sub-Saharan Africa from Senegal to South Sudan. Found along the northern savanna, it is often seen in Murchison Falls and Queen Elizabeth National Park, Uganda; Garamba and Virunga National Park, and the Democratic Republic of the Congo, as well as grassy floodplains of South Sudan. Kob are found in wet areas (such as floodplains), where they eat grasses. Kob are diurnal, but inactive during the heat of the day. They live in groups of either females and calves or just males. These groups generally range from five to 40 animals.
Among the kobs of eastern Africa, the Ugandan kob (Kobus kob thomasi) appears on the coat of arms of Uganda, and white-eared kobs (Kobus kob leucotis), found in South Sudan, southwest Ethiopia, and extreme northeast Uganda, participate in large-scale migrations.
The kob resembles the impala but is more robust. However, males are more robust than females and have horns. Males have shoulder heights of 90–100 cm (3.0–3.3 ft) and an average weight of 94 kg (207 lb). Females have shoulder heights of 82–92 cm (2.69–3.02 ft) and weigh on average 63 kg (139 lb). The pelage of the kob is typically golden to reddish-brown overall, but with the throat patch, eye ring, and inner ear being white, and the forelegs being black at the front. Males get darker as they get older. Those of the white-eared kob (K. k. leucotis), which is found in the Sudd region (the easternmost part of their range), are strikingly different and overall dark, rather similar to the male Nile lechwe, though with a white throat and no pale patch from the nape to the shoulder. Both sexes have well-developed inguinal glands that secrete a yellow, waxy substance, as well as preorbital glands.
The kob's distribution from western Africa to central East Africa is patchy. It inhabits flat areas and open country close to permanent water, with consistent climate. It requires fresh graze and drinks daily. During the rains, kob frequent short grasses and keep them short. Since it is dependent on water, the kob does not wander far into arid areas. Kob gather on and move from one pasture to another, coinciding with seasonal changes. In flooded areas, they may travel hundreds of kilometers, and dry-season walks to water may take 10 km or more. Grasses preferred by kobs are Hyparrhenia species, Brachiaria brizantha, Setaria gayanus, Chloris gayana, and Echinochloa and Digitaria spp.
Social behavior and life history
Kob have few strong social bonds, but females can live in herds numbering in the thousands. They move more and are more social than territorial males. Females are at the front of the daily movements to water. Individuals learn where to go from their mothers. However, in larger herds, the females will take their signals from other females. Males are also present in the migratory herds and will follow the females. All-male herds may number in the hundreds and accompany females as they travel during dry season.
The social and reproductive organization of kob can vary. When in average or low population densities, males establish conventional territories and do not travel much. Adult males try to establish their territories in the best habitat available, which are inhabited by herds of females and their young. Herds are fluid and change in size and structure as individuals travel to find green vegetation. Nonterritorial males, particularly young males, live in bachelor herds and are segregated from the females by the territorial males. On floodplains, where kob are densely populated, around two-thirds of the territorial males establish traditional territories, while the rest live in clustered territories known as leks. These clusters are sometimes smaller than a single traditional territory. Lek clusters are located on patches of short grass or bare ground within comparably tall grassland. As such, these territories have little to no value other than to the males that reside in them. About eight or 9 of every 10 females visit leks to mate, trading spacing and food for mating success. Females and bachelor males live in large herds of up to 2000 and move through the leks, which are surrounded by high-quailty grass and are near waterholes and commonly traveled routes.
Conflicts between territorial Ugandan kob (K. k. thomasi) are usually settled with ritual and rarely actual fighting, whether in conventional territories or leks. A male usually needs only to walk in an erect posture towards the intruder to displace him. Neighboring males in leks do the same thing when they encounter their borders. Lek-holding white-eared kobs fight more often. Ugandan kob do sometimes sustain serious or fatal injuries, especially when control of a territory is at stake. Fights usually involve the combatants clashing, pressing and twisting each other with their horns head-on. However, a neighbor may attack from the rear or side. In lek clusters, the most dominant males occupy the center. The number of males in the center of a lek cluster ranges from three to seven, and their leks are the most clustered and they monopolize copulations with estrous females. Replacement of males in leks are much more common than in traditional territories, and most males are able to stay in the centre positions for only a day or two and rarely up to a week. This is largely due to intense competition and because most males leave their territories to feed and drink. Centrally located males reduce their chances of being replaced by leaving to feed during periods of relative calmness, yet they are not able to get enough food and water and have to eventually leave their leks. However, a male can gain enough energy after a week or two, and try to take back his position. At every lek cluster, males are always waiting take or retake a central lek. Males in traditional territories are able to stay for at least a year or two.
Females have their first ovulation at 13–14 months of age and have 20–26 day intervals between estrous cycles until they are fertilized. Males from traditional territories and leks have different courtship strategies. Males of traditional territories will herd females and keep them in their territories. Lek males try to do the same, but usually fail. They have to rely on advertising themselves. Kob courtship may last as short as two minutes, and copulation may only last a few seconds. At leks, a female may mate up to 20 times with at least one of the central males in a day. After an eight-month gestation period and giving birth, estrus may commence 21–64 days later. For their first month, calves hide in dense vegetation. Mother and calf can identify each other by their noses. As they get older, calves gather into crèches. When they are three to four months old, the young enter the females' herds and stay with mothers until six to seven months, by which time they are weaned. When they mature, males join bachelors groups.
Kob populations have been decimated by hunting and human development. The Uganda kob became extinct in southwestern Kenya and northwestern Tanzania due to the expansion of human settlements and agriculture. However, there are good populations of this subspecies in Murchison Falls and Queen Elizabeth National Park in Uganda and Garamba and Virunga National Park in the Democratic Republic of the Congo.
Buffon’s kob (Kobus kob kob) are protected in several parks, including Niokolo-Koba in Senegal, Comoe in Côte d'Ivoire, Arly-Singou in Burkina Faso, Mole and Bui in Ghana, Pendjari in Benin, Waza, Benoué and Faro National Parks of the North Province of Cameroon, Zakouma in Chad, and Manovo-Gounda-St. Floris and Sangba in the Central African Republic.
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