Permafrost in the Arctic is thawing faster than ever, according to a new US government report that also found Arctic seawater is war...
lunedì 7 settembre 2015
Mysterious Death of 60.000 Saiga Antelopes
Mysterious causes have claimed the life of 60,000 saiga antelopes in central Kazakhstan.
As Steffen Zuther and his team of fellow wildlife experts travelled to Kazakhstan in time for the calving period of one saiga herd, several animals had already been reported dead on the ground.
These antelopes, boding well with the steppe of Kazakhstan, are threatened by a mysterious cause of death. Within just four days of the team’s arrival, 60,000 saiga antelopes were dead. Those were all the individuals in one herd.
Baffled, veterinarians in the area and international experts have since tried to find out what causes these alarming deaths. The 60,000 saiga antelopes were not alone. Similar reports from around Kazakhstan came in and concerned other herds that had likewise collapsed in a mysterious manner. The alarming deaths stopped by June, yet they counted over half of the state’s total herd which in 2014 counted 257,000 individuals.
“The extent of this die-off, and the speed it had, by spreading throughout the whole calving herd and killing all the animals, this has not been observed for any other species. It’s really unheard of”.
Perhaps not for another species. But in 1988, a similar event took place, when 400,000 saigas died suddenly in a matter of days. As the time, the researchers investigating the deaths listed Pasteurellosis as the main trigger of death.
Saigas have been listed as a critically endangered species by the International Union for the Conservation of Nature. The population is not so spread. While some herds can be found in Kazakhstan, one smaller herd dwells in Russia and another in the steppe of Mongolia.
In Kazakhstan, the herds come together at times, particularly during cold winters and migration periods. As the calving period approaches they split once more. It was during the early summer calving period that the en-masse die-off began.
The saiga antelope is key to the ecosystem that it inhabits. The cold, harsh winters in the grassland steppe of Kazakhstan keep plants from decomposing. As the saigas are grazing, their noses are breaking the organic matter, aiding it to be absorbed in the soil as nutrients. Of course, they are also being preyed upon by the steppe predators.
With such large numbers of saigas dead, the ecosystem they are part of faces severe disruptions. The veterinarians and scientific teams took samples from the saigas that died, as well as from all components of their environment, hoping that they would find what exactly killed them.
However, no analysis yielded any noteworthy results or out of the ordinary patterns. Neither did the necropsies performed on the dead saigas. However, the researchers found that the mothers were the first to collapse to the mysterious death. They were followed by their calves, which indicates that whatever is causing the mass dying is transmitted through the mother’s milk.