Saiga Antelope
Saiga antelope are peculiar looking relatives of goats, sheep, and antelope. During the Ice Age they roamed the Mammoth Steppe from England to the Mackenzie Delta of the Northwest Territories. Today, they are limited to the arid steppes and semi-deserts of central Asia around Kazakhstan and Mongolia. Fossil bones indicate that ice age saiga antelope were about 10 to 15 per cent larger than their modern counterparts. This suggests that, compared to their habitat today, the ice age steppes of Beringia supported richer vegetation with less competition for resources.
Saiga antelope were well adapted to the ice age Mammoth Steppe. Their large, bulbous nose with downward pointing nostrils contains a series of chambers with mucus glands to warm and moisten cold, dry air. These nostrils were also effective at filtering the dusty air that was kicked up when large herds moved accross the dry landscape. The saiga's low-slung head, short limbs and gait are adaptations for efficiently travelling long distances on flat terrain in search of food.
One of the biggest factors limiting the current and ancient distribution of saiga antelopes is snow depth. It might initially seem counterintuitive for an ice age mammal to not like snow, but deep snow is a real problem for saiga antelope. For the most part, they cannot dig through and forage on grasses when the snow is more than 30 centimetres thick. They also have difficulty dealing with hard, crusty snow that forms when snow melts and re-freezes. In Kazakhstan, these events are called dhzuts, and are known to cause massive die-offs among saiga antelope.
Yukon's History of Saiga Antelope
Fossils of saiga antelope are rare in Yukon. They have been found along the Old Crow River and in the Bluefish Caves of northern Yukon. A series of radiocarbon dated fossils from across Beringia indicate that the first saiga antelope likely crossed the Bering land bridge eastward into Alaska around 40,000 years ago. This was a relatively warm period during the Ice Age, prior to the peak cold and dry times.
A lack of radiocarbon dated fossils between 20,000 and 15,000 years ago points to a period of population decline for many ice age mammals, including the saiga antelope. Their populations rebounded as temperatures rose and they continued their journey eastward, reaching the Mackenzie Delta around 14,000 years ago. Saiga antelope got stuck in the North and did not make it south of the continental glaciers.
Unfortunately, like so many ice age animals, saiga did not survive in North America after the Ice Age. Their formerly widespread ice age distribution was reduced back to their core area of central Asia. Genetic studies on both ancient and modern bones indicate they have suffered repeated periods of significant population reduction, around 12,000 years ago and in recent historic times, in particular at the end of the Soviet era. Estimates suggest that their populations have crashed by 95 per cent in the last few decades, and their numbers continue to dwindle. They are currently listed as Critically Endangered by the International Union on Conservation of Nature's Red List of threatened species.
Want to keep learning? Check out the Beringian Research Notes on the saiga antelope.