They also lived in Beringian North America during the Pleistocene. Today, the dominant subspecies (S. t. tatarica) is only found in one location in Russia (in The Republic of Kalmykia) and three areas in Kazakhstan (the Ural, Ustiurt and Betpak-Dala populations). A proportion of the Ustiurt population migrates south to Uzbekistan and occasionally Turkmenistan in winter. It is extinct in People's Republic of China and southwestern Mongolia. It was hunted extensively in Romania and Moldova until it became extinct in those regions at the end of the 18th century. The Mongolian subspecies (S. t. mongolica) is found only in western Mongolia.[3]
Taxonomy and phylogeny
The scientific name of the saiga is Saiga tatarica. It is the sole extant member of its genus and is classified under the family Bovidae.[4] This species was first described by Swedish zoologist Carl Linnaeus in the 12th edition of Systema Naturae (1766). Linnaeus gave it the name Capra tatarica.[5] The relation between the saiga and the Tibetan antelope (Pantholops hodgsonii) have long been debated. English zoologist Reginald Innes Pocock classified them under different subfamilies in 1910.
In 1945, American paleontologist George Gaylord Simpson classified both in the tribe Saigini under the same subfamily, Caprinae. Subsequent authors were not certain about the relationship between the two, till phylogenetic studies in the 1990s revealed that though morphologically similar, the Tibetan antelope is closer to Caprinae while the saiga is closer to Antilopinae.[6]
In a revision of the phylogeny of the tribe Antilopini on the basis of nuclear and mitochondrial data in 2013, Eva Verena Bärmann (of the University of Cambridge) and colleagues showed that the saiga is sister to the clade formed by the springbok (Antidorcas marsupialis) and the gerenuk (Litocranius walleri).[7] The study noted that the saiga and the springbok could be considerably different from the rest of the antilopines; a 2007 phylogenetic study suggested that the two form a clade sister to the gerenuk.[8] The cladogram below is based on the 2013 study.[7]
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- S. t. mongolica Bannikov, 1946: Also known as the Mongolian saiga. It is sometimes treated as an independent species, or as subspecies of S. borealis. Confined to Mongolia.
- S. t. tartarica (Linnaeus, 1766): Also known as the Russian saiga. Occurs in central Asia.
Evolution
Saiga antelope skull and taxidermy mount on display at the Museum of Osteology.
Fossils of saiga, concentrated mainly in central and northern Eurasia, date back to as early as the late Pleistocene (nearly 0.1 Mya).[10] An extinct species of Saiga, S. borealis, has been identified from the Pleistocene of northern Eurasia.[11] Fossils excavated from the Buran Kaya III site (Crimea) date back to the transition from Pleistocene to Holocene.[12] The morphology of saiga does not seem to have changed significantly since prehistoric times.[2]
Before the Holocene, the saiga ranged from as far west as modern day England and France to as far east as northern Siberia, Alaska and probably Canada. The antelope gradually entered the Urals, though it did not colonise southern Europe. A 2010 study revealed that there has been a steep decline in the genetic variability of the saiga since the late Pleistocene-Holocene, probably due to a population bottleneck.[13]
Characteristics
The saiga stands 61–81 centimetres (24–32 in) at the shoulder, and weighs 26–69 kilograms (57–152 lb). The head-and-body length is typically between 100 and 140 centimetres (39 and 55 in). A prominent feature of the saiga is the pair of closely spaced, bloated nostrils directed downward. Other facial features include the dark markings on the cheeks and the nose, and the 7–12 centimetres (2.8–4.7 in) long ears.[2][14] During summer migrations the saigas' nose helps filter out dust kicked up by the herd and cools the animal's blood. In the winter it heats up the frigid air before it is taken to the lungs.[citation needed]
The coat shows seasonal changes. In summer, the coat appears yellow to red, fading toward the flanks. The Mongolian saiga can develop a sandy colour. The coat develops a pale grayish brown colour in winter, with a hint of brown on the belly and the neck. The ventral parts are generally white. The hairs, that measure 18–30 millimetres (0.71–1.18 in) long in summer, can grow as long as 40–70 millimetres (1.6–2.8 in) in winter. This forms a 12–15 centimetres (4.7–5.9 in) long mane on the neck. Two distinct moults can be observed in a year: one in spring (April to May) and another in autumn (late September or early October to late November or early December). The tail measures 6–12 centimetres (2.4–4.7 in).[2][9]
Only males possess horns. These horns, thick and slightly translucent, are wax-coloured and show 12 to 20 pronounced rings. With a base diameter of 25–33 millimetres (0.98–1.30 in), the horns of the Russian saiga measure 28–38 centimetres (11–15 in) in length; the horns of the Mongolian saiga, however, reach a maximum length of 22 centimetres (8.7 in).[2][9]
Ecology and behaviour
Male saiga
Saiga, like the Mongolian gazelles, are known for their extensive migrations across the steppes that allow them to escape natural calamities.[16] Saiga are highly vulnerable to wolves. Juvenile saiga are targeted by foxes, steppe eagles, golden eagles, dogs and ravens.[2]
Habitat and distribution
Saiga in West Kazakhstan. 2017
Numerous evidence show the importance of the antelope to Andronovo culture settlements. Illustrations of saiga antelopes can be found among the cave paintings that were dated back to seventh-fifth century B.C. Moreover, saiga bones were found among the remains of other wild animals near the human settlements.[18] The fragmented information shows an abundance of saigas on the territory of modern Kazakhstan in the 14th-16th centuries. The migratory routes ranged throughout the country's area, especially the region between Volga and Ural rivers was heavily populated.[19] The population's size remained high until the second half of the 19th century when excessive horn export began. The high price and demand for horns drove radical hunting. The number of animals decreased in all regions and the migratory routes shifted southward.[20]
After a rapid decline they were nearly completely exterminated in the 1920s, but they were able to recover. By 1950, two million of them were found in the steppes of the USSR. Their population fell drastically following the collapse of the USSR due to uncontrolled hunting and demand for horns in Chinese medicine. At one point, some conservation groups, such as the World Wildlife Fund, encouraged the hunting of this species, as its horn was presented as an alternative to that of a rhinoceros.[21]
Today, the populations have again shrunk enormously — as much as 95% in 15 years.[22] The saiga is classified as critically endangered by the IUCN. An estimated total number of 50,000 saigas survive today in Kalmykia, three areas of Kazakhstan and in two isolated areas of Mongolia. Another small population in the Pre-Caspian region of Russia remains under extreme threat.[23]
Cherny Zemli Nature Reserve was created in Russia's Kalmykia Republic in the 1990s to protect the local saiga population. Kalmykia's president Kirsan Ilyumzhinov announced 2010 as the Year of Saiga in Kalmykia. In Kazakhstan, the number of saiga was found to be increasing, from around 21,000 at the beginning of this millennium to around 81,000 in January 2010.[citation needed] However, in May 2010, an estimated 12,000 of the 26,000 Saiga population in the Ural region of Kazakhstan have been found dead. Although the deaths are currently being ascribed to pasteurellosis, an infectious disease that strikes the lungs and intestines, the underlying trigger remains to be identified.[24] In May 2015, what may be the same disease broke out in three northern regions of the country.[25] As of 28 May 2015, more than 120,000 saiga antelope have been confirmed dead in the Betpak-Dala population in central Kazakhstan, representing more than a third of the global population.[26] By April, 2016, the saiga appear to be making a comeback, with increase of population from 31,000 to 36,000 in the Betpak-Dala area.[27]
Kazakhstan in November 2010 reaffirmed a ban on hunting saiga antelopes, and extended this ban until 2021, as the Central Asian nation seeks to save the endangered species.[28]
The Mongolian saiga (S. t. mongolica) is found in a small area in western Mongolia around the Sharga and Mankhan Nature Reserves.[29]
Currently, only the Moscow Zoo and Askania-Nova keep saigas.[30] Cologne Zoological Garden and San Diego Zoo had them in the past. Pleistocene Park in northern Siberia plans to introduce the species.
Threats and conservation
Stuffed saiga herd at The Museum of Zoology, St. Petersburg
Under the auspices of the Convention on Migratory Species of Wild Animals (CMS), also known as the Bonn Convention, the Memorandum of Understanding (MoU) Concerning Conservation, Restoration and Sustainable Use of the Saiga Antelope was concluded and came into effect 24 September 2006.[32] The saiga's decline being one of the fastest population collapses of large mammals recently observed, the MoU aims to reduce current exploitation levels and restore the population status of these nomads of the Central Asian steppes.
In June 2014, Chinese customs at the Kazakh border uncovered 66 cases containing 2,351 saiga antelope horns, estimated to be worth over Y70.5 million (US$11 million).[33] At that price, each horn would cost over US$4,600.
In June 2015, E.J. Milner-Gulland (chair of Saiga Conservation Alliance) said, 'Anti-poaching needs to be a top priority for the Russian and Kazakh governments.'[15]
Hunting saiga
Saiga has been a target of hunting since prehistoric ages, when hunting was an essential means to acquire food. Saiga's horns, meat and skin have commercial value and are exported from Kazakhstan.Saiga horn, Cornu Antelopis, is one of the main ingredients in traditional Chinese medicine that is used as an extract or powder additive to the elixirs, ointments and drinks. Saiga horn's value is equal to rhinoceros horn, whose trade was banned in 1993. Cornu Antelopis is thought to be a cheaper substitute of rare rhino horn in most TCM recipes.[34] Although the hunting and trade is considered illegal, the horn products still can be found sold publicly and openly in a great variety of venues and businesses.[35]
Saiga's meat is compared to sheep's, it is considered to be nutritious and delicious. Numerous recipes for cooking the antelope's meat can be found.[36] In the period from 1955 to 1993 roughly 92 tonnes of meat were collected in Kazakhstan by killing more than five millions saigas.[20] Both meat and by-products are sold in the country and outside of it. About 45–80 dm² of skin can be yielded from one individual depending on its age and sex.[20] The skin is used to produce suede and box calf.
Physical barriers
Agricultural advancement and human settlements kept shrinking the habitat areas of the saigas since 20th century.[20] Occupants limited saiga's passage to water resources and the winter and summer habitats. The ever-changing face of steppe makes saiga search for new routes to their habitual lands. Nowadays, saiga populations' migratory routes pass five countries and different man-made constructions, such as railways, trenches, mining sites, and pipelines.[20] These physical barriers limit movement of the antelopes. There are reported cases that saiga herds were trapped within the fenced area and starved to death unable to find an exit.[37] Starting from 2011 Kazakhstan has built more than 150 km of wire fence at the border with Uzbekistan. This fence limits seasonal migration of not only saigas but smaller animals as well.[38] Although the concerns have been stated, the fences are still being built.Climatic variability
The saiga is dependent on weather and affected by climate fluctuations to the high extent due to their migratory nature.[39] Harsh winters with strong winds or high snow coverage disables feeding on the grass under the thick snow. Population size usually dramatically decreases after severe cold months.[20] Recent trend in climate change leads to increasing aridity of the steppe region, thus, deficiency of the grazing pastureland. It was estimated that already more than 14% of available pastureland are considered as degraded and useless.[40] Consequently, small steppe rivers dry faster limiting water resources to large lakes and rivers, which are usually populated by human settlements.[20] Moreover, high temperature in the steppe region leads to springtime floods, in which saiga calves can drown.[20]Cumulatively, these facts show that existence of saiga in the Anthropocene age is highly dependent on people.
Mass mortalities 1980 to 2015
For ungulates mass mortalities are not uncommon. In the 1980s there were several saiga die offs, and between 2010 and 2014 there was a die off every year. It was thought that the deaths could be linked to calving aggregation, which is when they are most vulnerable.[15] More recent research involving a mass die off in 2015 indicates warmer weather and attendant humidity caused bacteria common in saiga antelope to move into the blood stream and cause toxicity.[41]2015–2016 epizootic
In May 2015, uncommonly large numbers of saiga began to die from a mysterious epizootic illness suspected to be pasteurellosis.[15][42] Herd fatality is 100% once infected, with an estimated 40% of the species' total population already dead.[43] More than 120,000 carcasses had been found by late May 2015, while the estimated total population was only 250,000.[44]Biologist Murat Nurushev suggested that the cause might be acute ruminal tympany, whose symptoms (bloating, mouth foaming and diarrhea) had been observed in dead saiga antelopes.[45] According to Nurushev, this disease occurred as a result of foraging on a large amount of easily fermenting plants (alfalfa, clover, sainfoins and mixed wet green grass).[45] In May 2015, the United Nations agency which is involved in saiga conservation efforts issued a statement that the mass die-off had ended[citation needed]. By June 2015, no definitive cause for the epizootic had been found.[46]
At a scientific meeting in November 2015 in Tashkent, Uzbekistan, Dr. Richard A. Kock (of the Royal Veterinary College in London) reported that he and his colleagues had narrowed down the possible culprits. Climate change and stormy spring weather, they said, may have transformed harmless bacteria, carried by the saigas, into lethal pathogens.[47]
Pasteurella multocida, a bacterium, was determined to be the cause of death. The bacterium occurs in the antelopes and is normally harmless; the reason for the change in behavior of the bacterium is unknown.[48]
Now scientists and researchers believe the unusually warm and wet uncontrolled environmental variables caused the bacterium to enter the bloodstream and become poisonous. Blood poisoning is the likely cause of the most recent deaths[49] The change of the bacteria may be attributed to "the response of opportunistic microbes to changing environmental conditions".[50]
The Betpak-Dala saiga population in central Kazakhstan, which had the most deaths, increased from 31,000 after the epidemic to 36,000 by April 2016.[48]
In late 2016 there was a large loss of the population in Mongolia. The etiology was confirmed to be goat plague in early 2017.[51]
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