When more than 100,000 endangered saiga antelopes mysteriously died on the grasslands of Central Asia this spring, experts were baffled. Now they are getting closer to finding out why so many animals died.
The saiga succumbed to something that left their corpses with swollen bellies and blood in their noses and mouths, reports Dinara Urazova for Tengrinnews. Suspecting some kind of infectious agent, a group of specialists led by Steffen Zuther, the acting director of the Association for the Conservation of Biodiversity of Kazakhstan, tramped out onto the steppe and sampled grass, water and soil to find the culprit.
Preliminary results indicate that the saiga were killed by hemorrhagic septicemia, an infection caused by bacteria that rapidly multiply and produce toxins. "The researchers suspect that the pathogens were spread by ticks that populate the steppes in great numbers in late April [and] early May," Urazova writes.
More than 134,000 animals died in two weeks — nearly one-third of the worldwide population. And the recent scourge wasn't the first time the endangered antelopes have died in large numbers. In fact, saigas are known to be prone to mysterious massive die-offs, reports Henry Nicholls for Nature. He writes:
These usually occur when the females come together to calve in the spring. In 1984, such an event in the Ural Mountains resulted in the loss of 100,000 animals — 67% of the local population. There were several smaller-scale die-offs in the 2000s. But this year’s mass-death event among animals living in the Betpak-Dala region of Kazakhstan is much more significant as entire herds are dying.
The experts also preformed necropsies — animal autopsies — to see if they could find the cause of death. While the nature of the infection has been agreed upon, the experts still haven’t concluded which bacteria is responsible. Richard Kock, a wildlife veterinarian at the Royal Veterinary College in the U.K. told Nature in May that multiple types of bacteria could be acting in concert.
Tengrinnews reports that test results will be ready by the beginning of September. Once the mystery of the saiga die-off is solved, experts will turn their attention to another quandary — how to prevent mass deaths in the future.