Using the satellite imagery, taken between 2009 and 2014 by a variety of commercial observation satellites, scientists have been able to determine the population, distribution and movement patterns of the saiga in the northwest Caspian Lowlands in the Republic of Kalmykia and the Astrakhan region, where their numbers are about 5,000.
The use of satellite imagery, so far on a trial basis, has helped to count and track the animals in a highly accurate and non-invasive way, compared with more traditional methods such as using helicopters or ground vehicles for counting by hand. It has also helped scientists to understand the factors affecting the saiga, including the distribution of local livestock, as well as plant cover conditions.
Conducting their studies in the period between late November and early March of each year, scientists first task was to learn to distinguish the saiga from other local animals, including sheep, horses, cows, and camels. They did so in part via the use of color, with the saiga donning a white coat in the wintertime. Scientists also had to calculating the average length, width, length-to-width ratio, and height (based on shadow), converting these figures to pixels in the satellite imagery.
The data proved useful in determining not just the number of animals, but also their distribution across large areas, up to an area of 20×40 sq. km at once, as well as distance from other herds and animals. It also helped to determine the average number of animals in each herd, their average distance from one another within a heard, and their general geographic behavior. Distribution patterns helped to indicate whether the animals were grazing or moving.
The results, published in the study “On the Possibility to Identify the Saiga Antelope (Saiga tatarica) on Very-High Resolution Satellite Images,” can be found in the journal Doklady Biological Sciences. The study was conducted with assistance from the Saiga Conservation Alliance, a partner of the Wildlife Conservation Network, and the US Fish and Wildlife Service.
The saiga, which stand 0.6-0.8 meters tall at the shoulder, and weigh between 36-63 kilograms, are a grazing herbivore distinguishable by their unusual nose structure. Once stretching from the British Isles through to the western coast of North America, the areas which these animals inhabit has gradually declined over the course of many centuries.
In the 20th century, after facing near-extinction in the 1920s in Soviet Russia, conservation efforts were started by the government, helping to stabilize the population at nearly 2 million by the 1950s. However, with the collapse of the Soviet Union and the rise of uncontrolled hunting, poaching and smuggling, the species has faced one of the fastest population collapses ever observed in modern times.
The drop is said to have been driven largely by Chinese demand for the male saiga’s horn, which is said to be used for medicinal purposes. It is estimated that only about 50,000 saiga remain in the world, largely in an area around the Russian Caspian and in Kazakhstan.
Anna Yachmennikova of the Severtsov Institute told Sputnik that the saiga face an “ecological crisis” in Russia, and that the government has introduced fines of up to 2 million rubles (about $41,625 US) or 7 years in prison for illegal hunting of the antelope. Strict conservation efforts have been introduced in Kazakhstan, which has banned hunting the saiga until at least 2021, and its Russian populations currently inhabit nature preserves.