On a hot and humid Sunday, in May 2015, reports began coming in to the saiga research team in Kazakhstan of deaths at a calving site where about 62,000 saigas were concentrated. The team located the herd and on upon arrival at the site, recorded 100 deaths, which they estimated had died within the past one to two days. In the following two days, the count rose to 400, then 1,000, then 20,000. Nine days later there were no known survivors. Tragically, rangers at another site reported deaths among an aggregation of 8,000 saigas. A second team of scientists was formed and arrived at the site. By then, many hundreds of animals were sick or dying. And two days later, none had survived. Within three weeks from the first reported deaths, more than 200,000 saiga antelopes died in calving aggregations across several hundred kilometers of central Kazakhstan, representing more than eighty percent of the Betpak-dala population, and more than sixty percent of the global population of the species.