Saigas once lived across the steppes of central Asia, in lands stretching from Moldova to China. Hunting, for both meat and horns, caused a dramatic decline in their numbers throughout the 20th century, accelerating after the collapse of the Soviet Union and leaving them virtually extinct by the dawn of the 21st. A mass outbreak of infectious haemorrhagic septicaemia in 2015 threatened to finish the job, but since then there has been a truly remarkable recovery, with what's thought to be an eleven-fold increase in their numbers between 2015 and 2022. This is so great, in fact, that the species was removed from the international endangered species list in April 2023.
Today, however, saiga still live in only a fraction of their former domain. The great majority live in three areas of Kazakhstan, one of which crosses a short way across the southern border into Uzbekistan. Much smaller numbers are found elsewhere, with one population north of the Caucasus Mountains in southern Russia, and another way across in western Mongolia.
It was obvious enough to early naturalists that the saiga was an antelope, and it was distinctive and common enough (at the time) to be given its scientific name by Linnaeus as early as 1766. Like all antelopes, he placed it with the goats, but John Edward Grey gave it its own genus in 1843. This was before Darwin, so quite how saiga related to other antelopes wasn't even really a question he would have thought to ask. Once we figured out that evolution was definitely a thing, however, it became a different matter.
In 1945, American palaeontologist George Gaylord Simpson decided, on anatomical grounds, that the closest living relative of the saiga was the chiru (an animal I've looked at before), grouping the two together as a subgroup within the larger caprine subfamily that otherwise includes goats, sheep, and muskoxen. In the 1990s, genetic analysis showed that the two species were not closely related after all, and while the chiru was placed just outside the caprines, the saiga ended up as a weird aberrant branch within the antilopine subfamily belonging to neither of the two known subgroups: the gazelles and the dwarf antelopes.
More recent studies have scuppered that, showing that the saiga is, in fact, a member of the gazelle "tribe" alongside springbok and oribi, among others. The reason this took so long to work out is that the saiga is a pretty odd animal.
Saiga are of similar size and build to springbok, standing about 75 cm (2' 6") high at the shoulder, with males slightly larger than females. Their coat ranges from yellowish-grey to an almost reddish shade, and is much thicker in winter, making them look bulkier than they are. Only the males have horns, which tilt backwards but are otherwise relatively straight. While the horns of all other antilopine antelopes are black, those of the saiga have an amber hue. The tail is unusually short.
The teeth are also unusual, with the first set of premolars being greatly reduced, and missing altogether in some individuals. The real thing that makes them distinctive, however, is the nose.
While it is true that some of the dwarf antelopes have fleshy noses that they can inflate to hold in air, this reaches dramatic proportions in the saiga, to the point that they can almost be said to have a short trunk. The nasal bones, which are supposed to form the top of the snout (and form the bridge of the nose in humans) are extremely short, leaving a massive boneless gap in front of them, filled in life with an enormous nasal cavity with a soft fleshy roof.
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| The Antilopinae (click to enlarge) |
Saiga are plains-dwelling animals, avoiding hills and rugged terrain in general and living on the open steppe and in semi-desert. As one might expect, the largest part of their diet is grass, but the exact proportions change throughout the year, and according to what's available. For instance, grass forms over half their diet in the spring, when it is freshly grown, but other low-lying plants become important as the year progresses, with saltbush and forage kochia being particularly favoured.
They are gregarious animals, travelling in herds of up to 120 animals that migrate, usually in single file, across hundreds of miles of steppeland in search of new pastures before spreading out over a suitable area. Living in the arid lands that they do, waterholes can be important centres for socialisation, with smaller groups gathering together there to interact, and often leaving together. Unlike gazelles, they rarely leap, but they can run surprisingly fast - speeds of up to 80 km/h (50 mph) have apparently been recorded over short distances.
The rut takes place in December, when dominant males gather a dozen or more females - sometimes as many as fifty - into temporary harems. Like many animals with a similar breeding style, they put so much effort into attracting mates at this time of year that they have little left over for feeding, losing around a third of their body weight over the season and frequently dying in the process. They smear themselves with secretions from scent glands on their face and groin, trample the snow around them to make a large open space, and bellow loudly to demonstrate their physical fitness.
While most normal animals would bellow using their mouths, saiga instead make the noise through their noses; a case of a structure that evolved for one thing being coopted to do something else as well. They achieve this feat using muscles in the nose that allow it to flex and stretch, making the sound deeper as well as louder. Females and young also make nasal calls to one another, and the call of the adults at least are distinctive enough to allow scientists (and presumably other saiga) to distinguish individuals.
Pregnancy lasts around 138 days, so that the young are born in the late spring. Normally, when herd animals give birth, the mother heads off somewhere away from her fellows, and hides her single young under a bush while she goes off to feed. Saiga, however, are very different. Here, groups of three to five mothers gather together to give birth communally, preferably somewhere they perceive as safe with flat terrain that provides a good view of the surrounding countryside and ready access to nearby water.
Moreover, twins are extremely common, in some populations representing up to two-thirds of all births. The newborn saiga hides by pressing themselves flat against the ground in long grass, with the mothers drawing potential predators away by feeding elsewhere and returning to their calves two or three times a day.
Living in cold, mostly treeless, steppe country, saiga can be regarded as one of the last surviving animals that once dominated the "mammoth steppe" during the Ice Ages. Indeed, while we can't trace their fossil history back any further, they seem to have prospered during this time. While in historical times they have reached no further west than the River Prut (now the Romanian/Moldovan border) on several occasions during the Ice Ages they ranged as far as central, and even western, Europe. At their furthest, they inhabited southern France and England, reaching the latter around 12,000 BC. In the opposite direction, they reached not only eastern Siberia, but as far as the Yukon, apparently dying out in North America when the Ice Ages ended.
As climate changes in the future, moving away from the cold conditions that saiga prefer, it is possible that the recent gains in its population could be reversed again. For the moment, however, while not entirely safe, it is out of immediate danger. Six of the other 31 species of antilopine antelope that I have covered are not so lucky - mostly desert-dwelling animals from North Africa and the Middle East.
Nonetheless, that brings me to the end of the subfamily. Indeed, having already covered the bovines and caprines, I have now described over half of the world's species of antelope. Some day, I will probably come back to the others, but that will be at least a couple of years away. Throughout the course of 2025 I will instead be looking at a very different group of mammals, including both well-known species (at least from zoos or nature documentaries) and some rather less so.
[Photo by Alexandr Putilin, from Wikimedia Commons. Cladogram adapted from Bibi et al. 2013.]
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