Connochaetes Taurinus Taurinus – Blue Wildebeest
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Connochaetes taurinus taurinus – Blue Wildebeest Wildebeest (C. t. taurinus), which is from southern Africa and is the only subspecies within the assessment region (Ansell 1972; Grubb 2005). Assessment Rationale Listed as Least Concern as this species is numerous and occurs extensively throughout the assessment region, and is present within many protected areas across its range. In South African National Parks alone (six parks), there are an estimated 8,818–18,318 individuals and at least 44,689 animals in total (2013 counts), including 42,450 animals within the natural distribution range. This equates to 29,715 mature animals assuming a 70% mature Andre Botha population structure. Thus, we infer there are well over 10,000 mature individuals in the assessment region. There Regional Red List status (2016) Least Concern are no real threats to this subspecies, however, incidences National Red List status (2004) Least Concern of hybridisation with Black Wildebeest (Connochaetes gnou), with fertile offspring, do occur. Additionally, it is Reasons for change No change unknown whether any exotic subspecies have been Global Red List status (2016) Least Concern introduced into the region with resultant reduction in the genetic integrity of C. taurinus taurinus. Selective breeding TOPS listing (NEMBA) None for colour variants is common practice in the wildlife CITES listing None industry. These threats should be monitored and translocation regulations enforced to prevent Endemic No compromised individuals entering formally protected areas. “A more whimsical compound than the Gnu could Regional population effects: There is migration of scarcely have been thrown together, or a monster individuals across transfrontier parks and the border imagined of a more fantastical and anomalous between South Africa and Botswana, and no rescue effect exterior” (W. Cornwallis Harris 1840). is necessary as this subspecies is widespread and common within the assessment region. The historical migrations that existed in the Kalahari have been reduced due to the decimation of the Kalahari population (Spinage 1992) through the erection of veterinary fences and Taxonomy competition with cattle ranching (Estes & East 2009). The Connochaetes taurinus (Burchell 1823) population in the Limpopo National Park all originate from the Kruger National Park (Estes & East 2009) and ANIMALIA - CHORDATA - MAMMALIA - currently this population will most likely be a sink outside CETARTIODACTYLA - BOVIDAE - Connochaetes - taurinus of the Kruger National Park rather than generating rescue Synonyms: albojubatus, babaulti, borlei, cooksoni, effects for the assessment area. corniculatus, fasciatus, gorgon, hecki, henrici, johnstoni, lorenzi, mattosi, mearnsi, reichei, rufijianus, schulzi Distribution Common names: Blue Wildebeest, Blue and White- Formerly distributed from southern Kenya southwards to bearded Wildebeest, Brindled Gnu, Brindled Wildebeest, northern and eastern Namibia, Botswana, the Orange Common Wildebeest (English), Blouwildebees (Afrikaans), River in South Africa, and Mozambique (East 1999; Estes Inkonkoni (Ndebele, Xhosa, Zulu), Imbudumo, Imbuduma 2013; IUCN SSC Antelope Specialist Group 2016). Blue ehlaza (Ndebele), Kgôkông (Sepedi, Setswana), Wildebeest have also been introduced to regions outside Kgokong, Kgaranyane (Sesotho), Ingongoni, Ngongoni of their former range, such as the Eastern Highlands of (Swati), Khongoni, Khongoini (Venda), Hongonyi Zimbabwe, private farmland in Namibia and private game (Xitsonga), Inkonkoni enombala oluhlaza (Zulu) ranches south of their historical range in South Africa (East 1999; Estes & East 2009). They have never occurred Taxonomic status: Subspecies in Lesotho (Lynch 1994). Taxonomic notes: Generally, five subspecies are C. t. taurinus occurs naturally in Namibia, South Africa to recognised (IUCN SSC Antelope Specialist Group 2016), Mozambique north of the Orange River, from Mozambique including the Western White-bearded Wildebeest (C. t. mearnsi); the Eastern White-bearded Wildebeest to Zambia south of the Zambezi River, and from southwest (C. t. albojubatus); Nyassa Wildebeest (C. t. johnstoni); Zambia to southeast and southern Angola (IUCN SSC Cookson’s Wildebeest (C. t. cooksoni); and the Blue Antelope Specialist Group 2016). This species was the inhabitant of the northern Kalahari savannahs, which is Recommended citation: Tambling C, Viljoen P, Kotze A. 2016. A conservation assessment of Connochaetes taurinus taurinus. In Child MF, Roxburgh L, Do Linh San E, Raimondo D, Davies-Mostert HT, editors. The Red List of Mammals of South Africa, Swaziland and Lesotho. South African National Biodiversity Institute and Endangered Wildlife Trust, South Africa. The Red List of Mammals of South Africa, Lesotho and Swaziland Connochaetes taurinus taurinus | 1 Figure 1. Distribution records for Blue Wildebeest (Connochaetes taurinus taurinus) within the assessment region Table 1. Countries of occurrence within southern Africa Population Country Presence Origin A population estimate conducted during the late 1990s Botswana Extant Native (mainly from aerial surveys) revealed an approximate global abundance of 1,298,000 C. taurinus (East 1999), Lesotho Absent - with the Serengeti–Mara migratory population constituting Mozambique Extant Native 70% of that population (IUCN SSC Antelope Specialist Namibia Extant Introduced Group 2016). Of these, 150,000 were estimated to be C. t. taurinus, half of which were in protected areas, and South Africa Extant Native one quarter in conservancies or on private land (Estes Swaziland Extant Reintroduced 2013). More recently, however, the most current global population estimate of Common Wildebeest is Zimbabwe Extant Native approximately 1,550,000 individuals, largely attributed to the recovery of the Serengeti–Mara population to supported by naturally occurring populations in the approximately 1,300,000 (Estes & East 2009). Recent Kgalagadi Transfontier Park (KTP) and Botswana’s Central subspecies estimates include 130,000 C. t. taurinus, 5,000– Kalahari Game Reserve to the north (Smithers 1971; 10,000 C. t. cooksoni, and 50,000–75,000 C. t. johnstoni Skinner & Chimimba 2005), as well as in bushveld regions (Estes 2013). A decline in the C. t. albojubatus population in northern Botswana. has revealed a current estimate of 6,000–8,000 individuals (Estes & East 2009). This species is migratory in the KTP between the three borders with Namibia and Botswana. There is also East (1999) indicates that population densities estimated evidence of local migrations within the Kruger National by aerial surveys range from less than 0.15 animals / km² Park (KNP). In South Africa, the species was largely in areas such as Kafue, Etosha, Hwange and the central confined to the northern parts of the country north of the and southern Kalahari, to 0.6–1.3 animals / km² in areas Orange River (Estes & East 2009). They currently still such as KNP, North Luangwa, Selous and Kajiado, and occur throughout most of their historical range (Skinner & 3.6 animals / km² in Tarangire (IUCN SSC Antelope Chimimba 2005), although have been exterminated in Specialist Group 2016). Recent total counts in areas large proportions of the Northern Cape where, historically, where the species is abundant have produced population they occurred extensively in the Kalahari Thornveld, density estimates as high as 34–35 animals / km²; for Lowveld and Bushveld habitats (Estes & East 2009). They example, in the Serengeti and Ngorongoro Crater (IUCN have been widely introduced to all provinces, despite its SSC Antelope Specialist Group 2016). Within the natural range excluding the Western and Eastern Cape assessment region, the overall population is stable or (Figure 1). increasing with an estimated population size of well over Connochaetes taurinus taurinus | 2 The Red List of Mammals of South Africa, Lesotho and Swaziland 10,000 mature individuals. In South African national parks (six areas) alone, there are an estimated 8,818–18,318 animals (2013 count; Ferreira et al. 2013). Across the country, on both formally protected areas and private lands, there were at least 44,689 animals in 2013 occurring on 648 protected areas of wildlife ranches (Endangered Wildlife Trust unpubl. data). This total is reduced to 42,450 on 552 properties by only including areas within the natural distribution (Figure 1), which equates to 29,715 mature animals assuming a 70% mature population structure. Our population estimate is similar to that estimated in 2005 of approximately 40,000 to 45,000 (Estes & East 2009). At the time of the 2005 assessment the South African population was deemed to be increasing (Estes & East 2009). The largest subpopulation occurs on KNP, with the most recent estimate being 6,058–10,896 animals in 2012 (Ferreira et al. 2013). The subspecies is especially numerous on private land: for example, while there are more than 3,600 individuals in North West Parks alone, there are a further 17,000 animals on private land in the province (Power 2014). Unfortunately, the numbers of both Black and Blue Wildebeest on all private properties is unknown. The Andre Botha occupancy of Blue Wildebeest as displayed by Figure 1 is suspected to be an under-estimate. Generation length has been calculated as 8 years (Pacifici Blue Wildebeest are most predominantly associated with et al. 2013), which yields a 24 year three generation period savannah woodland and short grasslands, with the (1991–2015). Most subpopulations on protected areas availability of shade