Pseudois nayaur (Hodgson, 1833)
|
publication ID |
https://doi.org/ 10.5281/zenodo.6512484 |
|
DOI |
https://doi.org/10.5281/zenodo.6636926 |
|
persistent identifier |
https://treatment.plazi.org/id/03F50713-992E-FF96-06DC-FCA8F850FED6 |
|
treatment provided by |
Conny |
|
scientific name |
Pseudois nayaur |
| status |
|
Greater Blue Sheep
French: Bharal de "Himalaya / German: Blauschaf / Spanish: Cabra azul del Himalaya
Other common names: Bharal, Chinese Blue Sheep, Himalayan Blue Sheep, Tibetan Blue Sheep
Taxonomy. Ouvis nayaur Hodgson, 1833 ,
Himalayas, subsequently restricted to the Tibetan frontier of Nepal.
The genus is more closely related to the genus Capra than to Ouvis. P. nayaur will hybridize with domestic goats but not domestic sheep. Although the Greater Blue Sheep is larger in body, horn, and skull measurements than the Dwarf Blue Sheep ( P. schaeferi ), there is only a weak genetic difference between the two species. Monotypic.
Distribution. China (S Xinjiang, Qinghai, Gansu, S Nei Mongol, Ningxia, Shaanxi, Sichuan, Xizang & N Yunnan), N Pakistan, N India, Nepal, Bhutan, and N Myanmar. View Figure
Descriptive notes. Head-body 120-140 cm,tail 13-20 cm, shoulder height 80-91. 4 cm (males); weight 60-75 kg (males) and 35-55 kg (females). Horn length 38-76 cm (males) and 10-20 cm (females), distance between horn tips 57-82 cm (males), horn basal girth 23-34 cm (males). Horns of females much shorter and thinner and grow slightly outward, then backward. Males are over 30% larger than females. Horns of males grow outward, then backward, and curve downward with the tips usually pointing slightly upward. Body color is brownish-gray in summer and bluish-gray in winter. Tail and front of neck, chest, and all four legs are black; a black stripe along lower side of flank separates the body color from the white underside. The flank stripe is continuous with the black of the front of the hindlegs. The inside and back of limbs are white, as is the distinct rump patch. Females have gray instead of black markings. Diploid chromosome number is 54 but a specimen from Gansu Province, China, had a chromosome number of 56.
Habitat. Greater Blue Sheep inhabit elevations of 1200-5500 m; usually occur at high elevations and with highly variable annual precipitation. They occur at 4000-4900 m in Xizang in alpine sedge meadows and areas free of tall vegetation near talus or rough, precipitous terrain, and also in much lower, arid, hilly terrain. A high-quality habitat in Nepal consisted of 29% bare ground and 58% grass cover. They seldom enter forested areas. The ranges of Greater Blue Sheep and Siberian Ibex ( Capra sibirica ) are sympatric in some areas. Greater Blue Sheep often share foraging areas with livestock, especially during summer. In the Helan Mountains of northern China, in a protected area, Greater Blue Sheep occur at 2000-3000 m in montane grasslands, woodland steppe, conifer forest, subalpine shrublands and meadows and had a preference for montane woodland steppe. Availability of grass species in the genus Stipa probably most influenced foraging habitat selection. Major mortality occurred in winter and spring due to climatic conditions and poor forage quality. Mortality rate of rams 1-5— 4-5 years old was 0%-7-4%, that of rams 5-5-10-5 years old was 14:9%-25%, and that of rams 11-5-15-5 years old was 40-7%-100%. Percentage of rams that survived up to eight years old was 64:7% and that of rams that survived greater than 13 years was 7-8%. On the Tibetan Plateau, over 80% of males died between four and eleven years of age and at Dorpatan in Nepal, about 50% of Greater Blue Sheep died between birth and two years of age. Greater Blue Sheep in the Manang District of Nepal (population about 1000 animals) were the prey of Snow Leopards (Panthera uncia), which consumed 11-24% of the total number of blue sheep annually. Other mammalian predators are Gray Wolves (Canis lupus), Leopards (P. pardus) and Dholes (Cuon alpinus ), but large predators have been extirpated in many areas.
Food and Feeding. Greater Blue Sheep can obtain food resources from sparse, highelevation vegetation. Seasonal forage classes consumed vary regionally. In some areas diets are dominated by graminoids (up to 80%) during summer, but graminoids can decline to less than 50% in winter. In other areas, they feed mainly on sedges during summer. In Ladakh, India, Greater Blue Sheep and Tibetan Argali ( Ovis hodgsoni) were spatially segregated due to habitat preferences and did not compete for forage. There can be substantial diet overlap with livestock, which can have a strong influence on the availability of forage. In Xizang, there was spatial overlap with livestock during summer and diet and habitat separation during winter. Forbs dominated the Greater Blue Sheep diet at the start of the growing season in spring but decreased gradually. Browse intake increased during autumn and winter. In summer, the three forage classes (forbs, sedges, and browse) did not differ significantly. Sedges were the most frequently eaten forage by Greater Blue Sheep throughout the year, but shrubs dominated the winter diet. Diet and spatial overlap of Greater Blue Sheep and livestock was greatest in the summer and lowest between Greater Blue Sheep and domestic sheep and goats in winter. Greater Blue Sheep overlapped extensively with domestic Yaks because both used similar elevations and both consumed high proportions of browse. In northern China, graminoids constituted 58-:8% of summer diets. Winter diets consisted of 36:7% graminoids and nearly 50% browse, including tree leaves. In northern Nepal, Greater Blue Sheep diet also was dominated by graminoids (51%), and forbs and browse constituted about equal proportions. Greater Blue Sheep and domestic goats had the most similar diets, but differed in the proportions of the three forage classes consumed. In the Himachal Pradesh, India, the Greater Blue Sheep diet in winter was influenced mainly by the availability of graminoids. The increased intake of browse by Greater Blue Sheep in winter was due to the limited availability of graminoids because of their consumption by livestock in summer.
Breeding. Greater Blue Sheep usually mate in November—January and young are born in May-June. The mating season in one study area in Nepal was from mid-December to late January, with a peak in early January; parturition commenced on 23 May and probably peaked in mid-June, but births can extend into July. The gestation period is about 160 days. Most females give birth at age three. Twinning is rare. Estrus lasts one to four days with a peak of about 20-36 hours. The estrous cycle lasts about 25 days and females recycle if not impregnated. Creches, in which a larger number of nursing young temporarily associate with a few females, have been documented. Males join females to form mixed groups and actively court females with a variety of courtship displays. Dominant males, older than five years old, do most of the mating.
Activity patterns. Greater Blue Sheep are diurnal and are most active before 09:30 h and after 16:00 h but also have a feeding bout about midday. In Nepal, during rut in December, Greater Blue Sheep were least active during the warmest period of the day (13:30-15:00 h) and activity increased in late afternoon. In May-June, activity peaked later in the afternoon.
Movements, Home range and Social organization. Greater Blue Sheep are usually gregarious. On the Tibetan Plateau, female herds averaged 14-5 individuals and mixed herds 23-2 individuals. In one area in Nepal, 66% of males were in mixed herds before rut and 80% during rut. In the Helan Mountain region in northern China, densities ranged from 3:6 ind/km? in spring to 4-6 ind/km?® in summer of the following year. Herds consisted of an average of 4-2 individuals in winter and 5-6 in spring and summer. Home ranges were 3-7 km? for males and 2-5-5 km? for females in winter. In other areas of China, densities were 3-6-5-3 ind/km” in better-quality habitats; in Nepal they ranged from a low of 0-7 ind/km? to 6-6-10-2 ind/km?. Adult sex ratios and other population parameters vary widely among areas. In the Manang District, Nepal, mean group size was 15-6, with smaller groups in winter than other seasons probably due to lower forage abundance and quality. Adult sex ratios per 100 females were 93-7 males in spring, 126-9 in autumn and 91-7 in winter. The population consisted of 34% adult males, 32% ewes, 15% yearlings, and 19% lambs. The lamb per 100 ewe ratios were 52-5 in spring, 70 in autumn and 55-4 in winter. Yearling per 100 ewe ratios were 32-9 in spring, 59-9 in autumn and 38-1 in winter. Yearling to female ratios on the Tibetan Plateau usually were from 26:100 to 40:100. Mother-young groups were most numerous in spring and male-female groups were present only in winter. Adult males and females are not always segregated in separate herds during the non-mating period.
Status and Conservation. Classified as Least Concern on The IUCN Red List. Locally common in many areas. Probably the most numerous ungulate in western China, where some populations have remained stable or slightly increased. In the Helan Mountain region of northern China within a protected area devoid of livestock, the Greater Blue Sheep population exceeds 10,000 animals. There are a minimum of 10,000 Greater Blue Sheep in north-western Xizang. In Ladakh, India, in the late 1980s, there were c.11,000 Greater Blue Sheep, and in Nepal ¢.10,000. In many areas, subsistence and commercial poaching, lack of government-sponsored wildlife conservation and management programs and habitat degradation by livestock are concerns. Most populations are unmonitored and their statuses unknown. In Pakistan, a sarcoptic mange infection probably transmitted by livestock caused the death of many Greater Blue Sheep. The potential for competition between Greater Blue Sheep and livestock is high because in many areas both prefer alpine meadows during summer. There is a need to add protected areas and prioritize Greater Blue Sheep and other wildlife by reducing or excluding livestock, in coordination with incentive-driven wildlife conservation programs at the community level.
Bibliography. Allen (1940), Aryal et al. (2010), Bunch, Wang Shiguan, Zhang Yaping et al. (2000), Dagleish et al. (2007), Ellerman & Morrison-Scott (1966), Feng Jiang et al. (2001), Fox & Johnsingh (1997), Groves (1978), Groves & Grubb (2011), Grubb (2005), Harris (2007, 2008), Harris & Loggers (2004), Harris & Miller (1995), Harris et al. (1999), Hess et al. (1997), Kusuda et al. (2006), Liu Yande et al. (2007), Liu Zensheng, Wang Xiaoming, Li Zhigang et al. (2005), Liu Zensheng, Wang Xiaoming, Teng Liwei & Cao Lirong (2007), Liu Zensheng, Wang Xiaoming, Teng Liwei, Cui Duoying & Li Xinging (2008), Lovari & Ale (2001), Ludwig & Fischer (1998), Lydekker & Dollman (1924), MacKinnon (2008), Mishra, Madhusudan & Datta (2006), Mishra, Van Wieren et al. (2004), Namgail et al. (2004), Oli (1994), Oli & Rogers (1996), Rabinowitz & Khaing (1998), Ren Junrang & Yu Yuqun (1990), Roberts (1997), Schaller (1977, 1998), Shrestha & Wegge (2008a, 2008b), Shresta et al. (2005), Suryawanshi et al. (2010), Wang Xiaoming & Hoffmann (1987), Wang Sung et al. (1997), Wang Xiaoming, Cao Lirong et al. (2006), Wang Xiaoming, Liu Zhensheng et al. (2005), Wegge & Oli (1997), Wilson (1984), Wollenhaupt et al. (1997), Woodford (2003, 2006), Zeng Bo et al. (2008).
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.
