Overview

Brief Summary

Biology

The Critically Endangered hirola is a grazing antelope that can be found feeding most intensively on the grassy plains in the early morning and evening, using its large molars to chew the coarse grass (2). Like many other mammals inhabiting the hot, dry plains of Africa, the hirola can go for long periods without drinking, and survives drought by storing fat and avoiding unnecessary energetic activity (2). Females and their young form groups of between 5 and 40 individuals (2), while the role of mature males depends on population density and ecological factors (3). In areas and times of abundant food, males are thought to defend territories, and mark the area boundaries with faeces and secretions from the facial glands (3). They then attempt to mate with females that come to feed in the territory (3). In other areas, males defend a group of females, firmly leading them into new feeding areas or herding them from the rear (3). When competing for females or defending their territories males can assume two fighting positions; they adopt an unusual kneeling position when fighting intensely, and a standing position when sparring (2). Hirolas mate mostly during the long rains in February and March (3), leading to a gestation that lasts about 240 days (5). Females separate from their group to give birth to a calf at the beginning of the short rains in October and November (2) (3). Newborn calves are vulnerable prey for jackals, dogs, hyenas, and large cats and eagles (2).
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Description

Numbers of this rare antelope have recently drastically declined and the species is now in danger of imminent extinction (2). As the sole surviving species of the once abundant Beatragus genus (3), the hirola's extinction would mean not only the loss of a species, but also the loss of an entire ancient antelope group. Discovered in 1888 by the big game hunter and zoologist H.C.V. Hunter (4), the hirola is a sandy-coloured antelope with long legs, body and face and a short neck (2). Male hirolas turn slate-grey as they age (2). The face is characterised by white 'spectacles' around the eyes linked by a narrow, white chevron (2) (5), and pronounced, dark scent-glands under the eyes become enlarged when excited, leading to the hirola's other name of 'four-eyed antelope' (4). The lyrate, heavily-ringed horns are beautiful but dangerous weapons, used in fights with rivals. The thick skin at the nape of the hirola's neck folds up behind the horns when the ears are pricked, offering a degree of protection against the sharp horns of an opponent (2). The black-tipped ears and long tail are startlingly white (2).
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MammalMAP

MAD MAMMAL MONDAY

The world’s rarest and most endangered antelope called Hirola is the sole survivor of a formerly diverse group, and is also named as a living fossil.  It was common throughout East Africa; the species has suffered a devastating decline in the last 30 years, with numbers plummeting from around 14,000 in the 1970s to an estimated 600 today. The surviving Hirola are threatened by drought, poaching and habitat loss. Intensive conservation efforts are needed if this rare and beautiful antelope is to survive. It was then restricted to the south-eastern coast of Kenya, just south of the border with Somalia.

The tiny antelope with a body length of 120-205 cm, Height: 88-134 cm and the Tail Length: 10-60 cm. The species has an elongated face with a slightly convex forehead. A white line, or chevron, passes from one eye to the other across the forehead, giving the Hirola the appearance of wearing spectacles. The long, thin tail is white, as are the ears, which are tipped with black. The horns are well developed in both sexes; these are lyre-shaped and conspicuously ringed for most of their length, and when fully developed can reach lengths of over 70 cm. Mostly they depend on the grazing lands change over time as they become unsuitable by the invasion of predators or large herds, drought, or over-growth of grasses. The largest known area grazed by a herd is over 100 square km.

According to their mating system Hirolas mate at the beginning of the long rainy season in March or April and gives birth at the beginning of the short rainy season in October and November. Gestation typically lasts 7 to 8 months and a single calf is born, though twins are possible. Females become sexually mature at 2 to 3 years of age, while males do not mate until they are large enough and dominant enough to successfully compete with other males, usually between 3 to 4 year old.

Hirola cluster in harems, consisting of a territorial male, several females, and their young. Small groups of bachelor males and yearlings also occur. Hirola form larger herds ranging in size from 15 to 40 individuals to many hundreds, depending on the time of year. During this time, smaller herds often exchange individuals before breaking apart from the larger group. This exchange of individuals helps decrease the likelihood of genetic drift and inbreeding within smaller herds. Most activity and grazing for hirola, takes place during the morning and evening hours. Please visit our blog at www.mammalmap.blog.com and our virtual museum at http://vmus.adu.org.za/

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Distribution

Hirola are found in the area between the Tana River in Kenya and the Juba River in Somalia. In 1963 a small population of about 20 individuals were introduced into the Tsavo East National Park from the South Garissa District.

Biogeographic Regions: ethiopian (Introduced , Native )

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Range Description

The Hirola is endemic to north-east Kenya and south-west Somalia. Historical distribution is estimated to have covered ca. 17,900 km² in Kenya and ca. 20,500 km² in Somalia (Bunderson 1981, East 1999, Butynski in press). In Kenya, Hirola currently occur between Garsen, Bura and Galma Galla/Kolbio over an area of ca. 8,000 km² (Butynski 1999). Current status in south-west Somalia is not known, but its former range has been badly affected by prolonged civil and military conflicts that continued up to early 2007.

There is a small translocated population in Tsavo East National Park, outside the species’ natural range. This originated from a translocation of 30 animals from Garissa District conducted in 1963. It is thought that most of these perished soon after release and that the size of the “effective founder population” was only 11 to 19 animals (Butynski 1999). A further 10 animals were translocated to Tsavo East in 1996 (Hofmann 1996).
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Range

Historically the hirola may have had a large distribution, but since the 1960s it has been confined to a rapidly shrinking corner of south-east Kenya and southern Somalia (2). It is now thought to possibly be extinct in Somalia (5).
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Physical Description

Morphology

Hirola have long legs, a long body, long face with a slightly convex forehead, and a relatively short neck. Total body length ranges from 1200 to 2050 mm, tail length from 300 to 450 mm, and height at the shoulder from 1000 to 1250 mm.

Generally a mixture of soft and coarser hairs that vary in color from sandy brown to slate grey cover the body. The ears are white with black tips and the tail is white. A white line passes across the forehead from one eye to the other creating a white emphasis around the eyes in the likeness of a mask.

The horns of both males and females are angular, curved, and slightly flared. They are ringed most of the length of the horn, and reach about 700mm in length when fully developed.

Range mass: 65 to 155 kg.

Range length: 1200 to 2050 mm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger; ornamentation

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Ecology

Habitat

Beatragus hunteri inhabits short-grass, seasonally arid, grasslands in dry acacia bush/scrub and forest-savannah mosaic habitats.

Suitable grazing lands change over time as they become unsuitable by the invasion of predators or large herds, drought, or over-growth of grasses. The largest known area grazed by a herd is over 100 square km.

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: savanna or grassland ; scrub forest

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Habitat and Ecology

Habitat and Ecology
Hirola inhabit semi-arid thorn bush, open bush grassland, to light woodland, and lush savanna grassland. Their preferred habitat is seasonally flooded, open grassland with scattered small shrubs and trees on well-drained soils with short leafy swards of grass formed by fire, or by the combined grazing pressure of wildlife and domestic livestock (Bunderson 1981, Butynski in press).

Systems
  • Terrestrial
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The remaining hirolas inhabit a narrow strip of seasonally arid, grassy plains (2).
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Trophic Strategy

Hirola are selective grazers, depending on short grasses. Occasionaly they have been oberserved to consume forbs. Their selectivity creates a need to follow the progress of newly sprouting grasses on the savannah and grasslands. If grasses grow too long, or if the grasses are disturbed by other grazers, they will move to another area.  Early evening and morning are the times of highest intensity feeding.

Hirola are able to survive lengthy periods without drinking by avoiding energetic activities and storing fats.

Grasses eaten include Panicum infestum, Digitaria rivae, and Latipes senegalensis. Forbes eaten include Portulaca oleraceae, Commelina erecta, and Tephrosia subtriglora.

Plant Foods: leaves; wood, bark, or stems

Primary Diet: herbivore (Folivore )

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Associations

It is likely that hirola play an important role in their habitats by influencing the growth and composition of plant communities. They also act as important prey species for large predators.

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In the Garissa area, hirola are preyed on by lions and hunting dogs, while in the Tsavo region, they are preyed on by cheetahs and lions. Hyenas and eagles prey on young soon after birth and before the mother and calf rejoin the herd. Poaching plays a role in the 'predation' of Hirola. The poachers are composed of military personal, civilians, herdsmen, and local gangs.

Hirola avoid predation by remaining in the herd, thereby relying on the vigilance of many individuals.

Known Predators:

  • lions (Panthera leo)
  • African wild dogs (Lycaon pictus)
  • cheetahs (Acinonyx jubatus)
  • hyenas (Hyaenidae)
  • eagles (Accipitridae)
  • humans (Homo sapiens)

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Known predators

Damaliscus hunteri is prey of:
Accipitridae
Homo sapiens
Panthera leo
Acinonyx jubatus
Lycaon pictus
Hyaeninae

This list may not be complete but is based on published studies.
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Life History and Behavior

Behavior

Preorbital gland secretions and posturing are used in male-male competition for access to females. Females are also likely to communicate their reproductive state via chemical cues.

Communication Channels: visual ; chemical

Perception Channels: visual ; tactile ; acoustic ; chemical

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Life Expectancy

In captivity, the average lifespan of hirola is 10.2 years. Lifespan in the wild is unknown (Huffman, 2001; Solomon Kyalo, pers.comm.).

Average lifespan

Status: captivity:
10.2 years.

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Lifespan, longevity, and ageing

Observations: Little is known about the longevity of these endangered animals, but one captive specimen lived 15.2 years (Richard Weigl 2005).
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Reproduction

Males compete among themselves for access to females and generally defend territories in which they maintain a harem of about 7 or 8 females. Male posturing includes head-flagging, marking of grass stems with preorbital glands, ground scraping with their hooves, and dung accumulations. Aggressive fighting between males is different from play-fighting by their stance. Earnest fights take place on their knees, whereas play-fighting takes place in an upright position.

Mating System: polygynous

Hirolas mate at the beginning of the long rainy season in March or April and gives birth at the beginning of the short rainy season in October and November. Gestation typically lasts 7 to 8 months and a single calf is born, though twins are possible. Females become sexually mature at 2 to 3 years of age, while males do not mate until they are large enough and dominant enough to successfully compete with other males, usually between 3 to 4 year old.

Breeding interval: Hirolas breed once yearly.

Breeding season: Breeding occurs in March and April.

Range number of offspring: 1 (low) .

Average number of offspring: 1.

Range gestation period: 7 to 8 months.

Range age at sexual or reproductive maturity (female): 2 to 3 years.

Range age at sexual or reproductive maturity (male): 3 to 4 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous

Females nurse and care for their young, who are capable of standing and running soon after birth. Calving females will separate from the group for the two weeks following birth. During this time the female and the calf are vulnerable to predation. When the calf has reached yearling status, it separates from the herd to join a sub group of yearlings.

Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female); post-independence association with parents

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Conservation

Conservation Status

Hirola populations suffered two drastic declines during 1976-1978 and then in 1995. In 1976-1978 the population declined from 14,000 individuals to about 2,000 for unknown reasons. The second decline saw the population decrease from ~2,000 to 300, this decline was attributed to hunting by poachers, competition with cattle, and loss of habitat due to human encroachment. The natural habitat of hirola occurs in southwestern Somalia and southeastern Kenya, though the Somalian population is thought to be extinct or only occuring in small patchy groups. Hirola are considered one of the world's rarest species.

Conservation efforts have been underway for this species since 1963 when they were reported to be threatened. A small population was relocated in Tsavo East National Park and placed under protection by the park. By 1996 the population had reached 56 individuals. That same year, 35 more individuals were relocated to the park from Kenya in the operation "Hirola Now or Never" to increase the genetic diversity of the park population.

Efforts are being made to study the wild populations and to immplement community programs to educate local people about this species and how to help conserve it.

(Solomon Kyalo, pers. comm.)

US Migratory Bird Act: no special status

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: critically endangered

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IUCN Red List Assessment


Red List Category
CR
Critically Endangered

Red List Criteria
A2cd

Version
3.1

Year Assessed
2008

Assessor/s
IUCN SSC Antelope Specialist Group

Reviewer/s
Mallon, D.P. (Antelope Red List Authority) & Hoffmann, M. (Global Mammal Assessment)

Contributor/s

Justification
Given a conservative estimate of generation time at nine years, the 85 to 90% decline (and continuing) since 1980 has occurred over three generations and meets the threshold for Critically Endangered under criterion A2, and on the basis of direct observation, decline in area of occupancy and habitat quality and levels of exploitation.

History
  • 2007
    Critically Endangered
  • 1996
    Critically Endangered
  • 1994
    Endangered
    (Groombridge 1994)
  • 1990
    Vulnerable
    (IUCN 1990)
  • 1988
    Rare
    (IUCN Conservation Monitoring Centre 1988)
  • 1986
    Rare
    (IUCN Conservation Monitoring Centre 1986)
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In 2012, Beatragus hunteri was included among the world's 100 most threatened species in a report by the IUCN Species Survival Commission and the Zoological Society of London.

(Baillie & Butcher 2012; Harvey 2012)

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Status

Classified as Critically Endangered (CR) on the IUCN Red List 2007 (1).
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Population

Population
In 1979, there were ca. 16,000 animals in Kenya on 17,900 km². Estimated numbers decreased from 12,500 in the early to mid-1970s to about 7,000 in 1977-83, followed by a drastic decline (85 to 90%) between 1983 and 1985 caused by the severe drought of 1984 (Butynski 1999). Ground surveys suggested a population of between 500 and 2,000 in Kenya in 1995/1996 (Andanje and Ottichilo 1999, Butynski 1999, Dahiye and Aman 2002). Somalia had ca. 2,000 Hirola in 1979, but has few, if any, today (Butynski 1999). Overall, numbers have fallen by 85 to 90% since 1980 and are still declining (East 1999, Butynski in press).

The translocated population in Tsavo East National Park numbers ca. 105 individuals, an increase from the 56 to 76 animals in 1995/1996 (Andanje and Ottichilo 1999, Butynski in press).

Population Trend
Decreasing
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Threats

Major Threats
Hunting, disease, drought, habitat loss, and competition with livestock. Lack of effective protection leaves it vulnerable to poaching. The development of the cattle industry, compounded by rinderpest and drought are continuing threats. The Tsavo population additionally faces predation by relatively high densities of large carnivores and competition from a greater variety of other wild herbivore species (but much lower numbers of cattle) than in its natural range (East 1999, Butynski in press).
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Numbers of hirola have declined severely; from 10,000 in the 1970s, to just 300 in 1995 (2). The remaining tiny population is now considered to be at risk of imminent extinction (2). Competition with cattle, severe drought, disease and poaching are all factors that have contributed to devastating hirola populations (3) (4). Unfortunately, the hirola's preference for areas that are used by livestock puts them at increased risk from diseases like rinderpest and tuberculosis (3).
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Management

Conservation Actions

Conservation Actions
This is one of the most highly threatened antelopes in Africa. Recommendations for the long-term conservation of the Hirola in Kenya have been included in a conservation action plan (Magin 1996) and a conservation evaluation report (Butynski 1999). These recommendations are now part of the current conservation and management plan for the Hirola in Kenya (Hirola Management Committee 2004) and are being acted upon by the Kenya Wildlife Service, in conjunction with the Hirola Management Committee and local conservation NGOs. There is an urgent need to improve the level of management and protection of the one natural population of Hirola, particularly in the Arawale National Reserve and in the Galma Galla/Kolbio region of Kenya. Community conservation and anti-poaching activities must be established over a large portion of the remaining range, but insecurity for conservation workers is an extremely serious problem in this region. Consideration should be given to establishing protected areas at Galma Galla and Lag Dere, and to expanding the Tana Primate National Reserve to the east to include at least 300 km² of prime habitat for Hirola (Butynski in press). There are only two Hirola in captivity.
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Conservation

In 1963, 10 to 20 hirola were released into Tsavo East National Park, Kenya, which grew to a population of 79 individuals by 1996. In 1996, another 29 hirola were translocated into the Tsavo East population, resulting in an estimated population of 100 hirola in Tsavo East National Park (6). The Hirola Management Committee (HNC) was also formed in 1994, with the aim of conserving this species in their natural range. The HNC created the Hirola Strategic Management Plan which outlined hirola conservation measures for the next five years (7). This included creating protected areas, reducing exposure to livestock diseases, careful monitoring, and promoting income generating eco-tourism for this unique species (7); measures that will hopefully pull this beautiful antelope back from the edge of extinction.
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Relevance to Humans and Ecosystems

Benefits

There are no known negative effects of hirola on humans.

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Hirola are sometimes hunted for meat, they have suffered drastic declines as a result of overhunting in the past.

Positive Impacts: food

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Wikipedia

Hirola

The hirola, also known as Hunter's hartebeest or "Hunter's antelope", is a Critically Endangered antelope species found on the border between Kenya and Somalia. They were discovered in 1888 by the zoologist H.C.V. Hunter [2][3] only extant member of the genus Beatragus.[4] The global hirola population is estimated at 300–500 animals, there are no hirola in captivity and the wild population continues to decline.[5][6][7] According to the International Union for Conservation of Nature Red List "The loss of the Hirola would be the first extinction of a mammalian genus on mainland Africa in modern human history." [8]

Description[edit]

The hirola is a medium sized antelope, tan to rufous-tawny in colour with slightly lighter under parts, predominantly white inner ears and a white tail which extends down to the hocks. It has very sharp, lyrate horns which lack a basal pedicle and are ridged along three quarters of their length. As hirola age their coat darkens towards a slate grey and the number of ridges along their horns increases. Hirola have large, dark sub-orbital glands used for marking their territories and give them the name "four-eyed antelope". They have white spectacles around their eyes and an inverted white chevron running between the eyes. The horns, hooves, udders, nostrils, lips and ear tips are black. Males and females look similar although males are slightly larger with thicker horns and darker coats.[2][9][10][11][12][13]

Several sources have recorded precise measurements from both captive and wild hirola. The following are maximum and minimum values taken from all sources: height at the shoulder: 99–125 cm, body weight: 73–118 kg, head and body length: 120–200 cm, horn length: 44–72 cm, horn spread (greatest outside width): 15–32 cm, tail length: 30–45 cm, ear length: 19 cm. It is not stated whether horn length was measured direct from base to tip or along the curve of the horn.[10][11][13][14] There is no data on how long hirola live in the wild but hirola in captivity have been known to live for 15 years.[5]

Taxonomy[edit]

Authorities agree that the hirola belongs in the subfamily Alcelaphinae within the family Bovidae but there has been debate about the genus in which it should be placed. The Alcelaphinae contains hartebeest, wildebeest and topi, korrigum, bontebok, blesbok, tiang and tsessebe.[13]

When it was first described the hirola was given the common name Hunter’s hartebeest. Despite this it was placed in the genus Damaliscus with the topi and given the scientific name Damaliscus hunteri.[2] Newer theories have classified it as a sub-species of the topi (Damaliscus lunatus hunteri) [15][16] and placed it within its own genus as Beatragus hunteri.[17][18][19][20]

Recent genetic analyses on karyotypic and mitochondrial DNA support the theory that the hirola is distinct from the topi and should be placed in its own genus.[19][21] They also indicate that the hirola is in fact more closely related to Alcelaphalus than to Damaliscus. Placing the hirola in its own genus is further supported by behavioural observations. Neither Alcelaphalus nor Damaliscus engage in flehmen, where the male tastes the urine of the female to determine oestrus. They are the only genera of bovids to have lost this behaviour. Hirola still engage in flehmen although it is less obvious than in other species.[22][23]

The genus Beatragus originated around 3.1 million years ago and was once widespread with fossils found in Ethiopia, Djibouti, Tanzania and South Africa.[11][18][24][24][25] The hirola is now the only extant member of the genus and is ranked forty third on the Zoological Society of London’s (ZSL) list of Evolutionary Distinct and Globally Endangered (EDGE) species.[26]

Ecology[edit]

The hirola is adapted to arid environments with annual rainfall of 300-600mm. Their habitats range from open grassland with light bush to wooded savannahs with low shrubs and scattered trees, most often on sandy soils.[27] Despite the arid environments they inhabit hirola appear to be able to survive independently of surface water.[27][28] Andanje [29] observed hirola drinking on only 10 occasions in 674 observations (1.5%) and all 10 observations of drinking occurred at the height of the dry season. Hirola do however favour short green grass [23] and in 392 of 674 observations (58%) hirola were grazing on growths of short green grass around waterholes.[29] This association with waterholes has led to false reports that hirola are dependent on surface water.[13]

Hirola are primarily grazers but browse may be important in the dry season.[30] They favour grasses with a high leaf to stem ratio and Chloris and Digiatta species are believed to be important in their diet.[11][23] Kingdon [11] does not consider the ecological requirements of the hirola unusual and in fact considers them to be more generalist than either Connochaetes spp. or Damaliscus spp. A vet who examined the digestive tract of several hirola concluded that they were well adapted to eating dry region grasses and roughage.[31] They feed on the dominant grasses of the region and Kingdon (1982) believes that quantity is more important than quality in the hirola’s diet.[23]

Hirola are often found in association with other species, particularly oryx, Grant’s gazelles, Burchell’s zebra and topi. They avoid Coke’s hartebeest, buffalo and elephant.[32] Whilst hirola avoid direct association with livestock they reportedly prefer the short grass in areas where livestock have been grazed.[30]

Social structure and reproduction[edit]

Female hirola give birth alone and may remain separate from the herd for up to two months, making them vulnerable to predation. Eventually the female will rejoin a nursery herd consisting of females and their young. Nursery herds number from 5–40 although the mean herd size is 7–9. They are usually accompanied by an adult male.[11][23][30][33]

Young hirola leave the nursery herd at around nine months of age and form various temporary associations. They may gather together in mixed or single sex herds of up to three individuals; sub-adult or subordinate adult males may form bachelor herds of 2–38 individuals; female sub-adults may join an adult male and; if no other hirola are present, young hirola may attach themselves to a herd of Grant’s gazelles or simply spend most of their time alone.[29][30]

Adult males attempt to secure a territory on good pasture. These territories are up to 7km2 and are marked with dung, secretions from the sub-orbital glands and by stamping grounds where males scrape the soil with their hooves and slash the vegetation with their horns.[30] It has been suggested that at low population densities adult males abandon territory defence and will instead follow a nursery herd.[34] Nursery herds do not defend a territory but do have home ranges which overlap the territories of several adult males.[32] The size of a nursery herd’s home range varies from 26–164.7 km2 with a mean size of 81.5km2.[29]

Nursery herds are relatively stable but bachelor herds are very unstable with a fission fusion dynamic. In the 1970s hirola were observed forming aggregations of up to 300 individuals to take advantage of scarce, but spatially clumped, resources during the dry season (Bunderson, 1985). Information is lacking on male territoriality and how it relates to mating success, how and when hirola join a herd and how new herds are established (Butynski, 2000).

Hirola are seasonal breeders with young being born from September to November.[11] Data on age of sexual maturity and gestation period are not available for wild hirola however in captivity gestation was around 7.5 months (227–242 days) with one female mating at 1.4 years old and giving birth at 1.9 years. Another pair of hirola mated when they were 1.7 years of age.[35] In captivity one of the main causes of mortality is wounds caused by intra-hirola aggression, including aggression between females.[5]

Threats[edit]

The reasons for the historic decline of the hirola are not known but is likely a combination of factors including disease (particularly rinderpest), poaching, severe drought, predation, competition for food and water from domestic livestock and habitat loss caused by bush encroachment as a result of the extirpation of elephants in the hirola's natural range.[13][36]

The Hirola prefers areas that are used by livestock which puts them at increased risk from diseases like tuberculosis.[37] Due to lack of protection they are also still very vulnerable to poaching and hirola are also threatened by predation and competition with other wild herbivores, particularly topi and Coke's hartebeest.[38]

Population size and distribution[edit]

The hirola's natural range is an area of no more than 1,500km2 on the Kenyan-Somali border but there is also a translocated population in Tsavo East National Park. The natural population in the 1970s was likely to number 10,000–15,000 individuals but there was an 85–90% decline between 1983 and 1985. A survey in 1995 and 1996 estimated the population to number between 500 and 2,000 individuals with 1,300 as the most reasonable estimate. The most recent survey took place in 2010 and estimated a population of 402–466 hirola (King et al., 2011).

A translocated population was established in Kenya’s Tsavo East National Park with translocations in 1963 and 1996 (Hofmann, 1996; Andanje & Ottichilo, 1999; Butynski,1999; East, 1999). The 1963 translocation released 30 animals and the first survey in December 1995 and concluded that there were at least 76 hirola present in Tsavo at the time. Eight months later a further 29 translocated hirola were released in to Tsavo, at least six of which were pregnant at the time (Andanje, 1997). By December 2000 the hirola population in Tsavo had returned to 77 individuals (Andanje, 2002) and by 2011 the population was estimated at 76 individuals (Probert, 2011; Probert et al., 2014).

Status and conservation[edit]

Hirola are critically endangered and their numbers continue to decline in the wild. There are between 300–500 individuals in the wild and none currently in captivity.[5][6][7]

Despite being one of the rarest antelopes, conservation measures for the hirola antelope have so far been marginal. The Arawale National Reserve was created in 1973 as a small sanctuary for the hirola but has been left unmaintained since the 1980s. In late 2005, four local communities in the Ijara District have, in collaboration with Terra Nuova, developed and put forward a proposal to formally establish the Ishaqbini Hirola Conservancy for the in situ protection of hirola.

In January 2010, Northern Rangelands Trust (NRT), Kenya Wildlife Service (KWS) and Ishaqbini Hirola Community Conservancy (IHCC), was funded by the United States Fish & Wildlife Service and USAID-Kenya, to conduct a survey to estimate the remaining population of this species in its natural range. The survey found only three areas with significant numbers of hirola and it is believed that there are no large herds or significant concentrations of hirola remaining in their natural range.

More recently a 23km2 predator proof fenced sanctuary has been constructed at Ishaqbini and a founding population of 48 hirola is breeding well within the sanctuary [39]

References[edit]

  1. ^ IUCN SSC Antelope Specialist Group (2008). Beatragus hunteri. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 5 April 2009. Database entry includes a brief justification of why this species is of critically endangered.
  2. ^ a b c Sclater, P. L. (1889) Description of Hunter's antelope. Proceedings of the Zoological Society 1889, 372–377.
  3. ^ http://www.arkive.org/hirola/beatragus-hunteri/
  4. ^ Grubb, P. (2005). "Order Artiodactyla". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. p. 675. ISBN 978-0-8018-8221-0. OCLC 62265494. 
  5. ^ a b c d PROBERT, J. (2011) The Tsavo hirola: current status and future management. MSc thesis. Imperial College London, UK.
  6. ^ a b King, J., Craig, I., Andanje, S. and Musyoki, C. (2011) They Came, They Saw, They Counted, SWARA, 34: (2).
  7. ^ a b James Probert, Ben Evans, Sam Andanje, Richard Kock and Rajan Amin. Population and habitat assessment of the Critically Endangered hirola Beatragus hunteri in Tsavo East National Park, Kenya . Oryx, available on CJO2014. doi:10.1017/S0030605313000902.
  8. ^ http://www.iucn.org/about/work/programmes/species/?11534/A-sanctuary-for-Hirola
  9. ^ Dracopoli, I. N. (1914) Some notes on the game animals of Jubaland. Uganda Natural History Society 4: 117–121.
  10. ^ a b Dorst, J. and P. Dandelot. (1970) A Field Guide to the Larger Mammals of Africa. Collins: London. 287.
  11. ^ a b c d e f g Kingdon, J. (1982) East African Mammals. An Atlas of Evolution in Africa. Vol. IIID. Bovids. Academic Press: New York. 395- 746.
  12. ^ Kingdon, J. (1997) The Kingdon Field Guide to African Mammals. Academic Press: London. 465.
  13. ^ a b c d e Butynski, T. M. (2000) Independent Evaluation of Hirola antelope (Beatrugus hunteri) conservation status and conservation action in Kenya. Kenya Wildlife Service and Hirola Management Committee: Nairobi, Kenya.
  14. ^ Best, G. A. F., Edmond-Blanc, F. and Courtenay Witting, R. (eds.) (1962) Rowland Ward’s Records of Big Game. 11th edition. Africa. Rowland Ward: London.
  15. ^ Haltenorth, T. and Diller, H. (1977) A Field Guide to the Mammals of Africa Including Madagascar. Collins: Cambridge, UK. 400.
  16. ^ Walther, F. R. (1990) Hartebeests, Grzimek's Encyclopedia of Mammals. New York: McGraw-Hill. 418–436.
  17. ^ Simpson, G. G. (1945) The principles of classification and a classification of mammals. Bulletin of the American Museum of Natural History 85: 1–350.
  18. ^ a b Gentry, A. W. (1990) Evolution and dispersal of African Bovidae. In: Bubenik, G. A. and Bubenik, A. B. (eds.). Horns, Pronghorns and Antlers. Springer-Verlag: New York. 195–227.
  19. ^ a b Pitra, C., Kock, R., Hofmann, R. and Lieckfeldt, D. (1998) Molecular phylogeny of the critically endangered Hunter’s antelope (Beatragus hunteri, Sclater 1889). Journal of Zoological Systematics and Evolutionary Research 36: 179–184.
  20. ^ Estes, R. D. (1999) Hirola: Generic status supported by behavioral and physiological evidence. Gnusletter 18: 10–11.
  21. ^ Kumamoto, A. T., Charter, S. J., Houk, M. L. and Frahm, M. (1996) Chromosomes of the Damaliscus (Artiodactyla, Bovidae): Simple and complex centric fusion rearrangements. Chromosome Research 4: 614–622.
  22. ^ Estes, R. D. (1991) The Behaviour Guide to African Mammals. The University of California Press: California. 611.
  23. ^ a b c d e Andanje, S. A. and Goeltenboth, P. (1995) Aspects of the Ecology of the Hunter's Antelope or Hirola (Beatrugus hunteri, Sclater, 1889) in Tsavo East National Park, Kenya. Kenya Wildlife Service, Research and Planning Unit: Nairobi, Kenya.
  24. ^ a b Gentry, A. W. and Gentry, A. (1978) Fossil Bovidae (Mammalia) of Olduvai Gorge, Tanzania: Part 1. Bulletin British Museum Natural History (Geology) 29: 289–446.
  25. ^ Thomas, H., Coppens, Y., Thibault. C. and Weidmann, M. (1984) Decouverte de vertebres fossiles dans le Pleistocene inferieur de la Republique de Djibouti. C. R. Academie des Sciences Paris 299: 43–48
  26. ^ EDGE (2011) List of Top 100 Mammals [online]. Available: http://www.edgeofexistence.org/mammals/top_100.php [September 2011].
  27. ^ a b Bunderson, W. T. (1981) Ecological separation of wild and domestic mammals in an East African Ecosystem. Logan, USA: Utah State University. 220–222.
  28. ^ Dahiye, Y. M. (1999) Population Size and Seasonal Distribution of the Hunter’s Antelope or Hirola (Beatragus hunteri, Sclater, 1889) in Southern Garissa, Kenya. MSc thesis: Addis Ababa University, Ethiopia.
  29. ^ a b c d Andanje, S. A. (2002) Factors limiting the abundance and distribution of hirola (Beatragus hunteri) in Kenya. PhD thesis: University of Newcastle Upon Tyne, UK.
  30. ^ a b c d e Bunderson, W. T. (1985) The Population, Distribution and Habitat Preferences of the Hunter’s Antelope Damaliscus hunteri in north-east Kenya. In litt. to J. Williamson, WCMC: Cambridge, UK. 13.
  31. ^ Hofmann, R. R. (1996) Hirola: Translocation to Tsavo NP and new scientific information. Gnusletter 15: 2–5.
  32. ^ a b Andanje, S. A. (1997) Hirola monitoring progress report: update analysis of animal movement, location and herding. Biodiversity Conservation Unit, Kenya Wildlife Service: Nairobi, Kenya.
  33. ^ Andanje, S. A. and Ottichilo, W. K. (1999) Population status and feeding habits of the translocated sub-population of Hunter's antelope or hirola (Beatragus hunteri, Sclater, 1889) in Tsavo East National Park, Kenya. African Journal of Ecology, 37: (1) 38–48.
  34. ^ Gosling, L. M. (1986) The evolution of mating strategies in male antelopes. Ecological Aspects of Social Evolution. Princeton University Press: Princeton. 244–281.
  35. ^ Smielowski, J. (1987) A note on the reproductive biology of the Hunter's antelope or hirola (Damaliscus hunteri – Sclater, 1889) in the zoo environment. Zoologische Garten 57: 234–240.
  36. ^ Magin, C. (l996a) Hirola Recovery Plan. IUCN Antelope Specialist Group in collaboration with the Kenya Wildlife Service and Hirola Task Force. IUCN: Nairobi.
  37. ^ Macdonald, D.W. (2006) The Encyclopedia of Mammals. Oxford University Press, Oxford.
  38. ^ The red list http://www.iucnredlist.org/details/6234/0
  39. ^ King, J., Craig, I., Golicha, M., Sheikh, M., Lesowapir, S., Letoiye, D., Lesimirdana, D., and Worden, J. (2014) Status of hirola in Ishaqbini community conservancy. Northern Rangelands Trust and Ishaqbini Hirola Community Conservancy, Kenya.

Further reading[edit]

  • Ever heard of the hirola? [1]
  • Who's heard of the hirola? [2]
  • Protection for weirdest species [3]
  • No safe haven for rarest antelope [4]
  • The Tsavo Hirola: Current status and future management [5]
  • Factors limiting the abundance and distribution of hirola (Beatragus hunteri) in Kenya [6]
  • Independent evaluation of Hirola Antelope Beatragus hunteri conservation status and conservation action in Kenya [7]
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