Mass die-off of saiga antelope causes global concern
More than 120,000 saiga antelope have been confirmed dead in central Kazakhstan; a major blow for conservation efforts given that saigas have in the past ten years only just started to recover from a global population size of less than 50,000 animals following a 95% crash in numbers.
Preliminary analysis indicates that a combination of environmental and biological factors is contributing to this catastrophic event, which has seen four large birth aggregations of this critically endangered antelope eradicated since mid-May this year. Primarily mothers and calves are amongst the carcasses; not a single animal survived in the affected herds.
"This loss is a huge blow for saiga conservation in Kazakhstan and in the world, given that 90% of the global saiga population is found in our country," Erlan Nysynbaev, vice-minister of the Ministry of Agriculture of Kazakhstan, stated. "It is very painful to witness this mass mortality. We established a working group that includes all relevant experts, including international ones, and are determined to identify the causes and undertake all possible efforts to avoid such events in the future."
Emergency mission
At the request of Kazakhstan, the Secretariat of the Convention on the Conservation of Migratory Species of Wild Animals (CMS) despatched an emergency mission with experts from the Royal Veterinary College in the United Kingdom and the Food and Agriculture Organisation to assist on the ground with post-mortem examination, analysis and to contribute to the working group.
"Authorities in Kazakhstan are responding quickly to this disaster and are working hard to solve the mystery behind this mass saiga die-off. I am pleased that the international expert mission we were able to send, at very short notice, is now contributing to these efforts," CMS executive secretary, Bradnee Chambers, said.
According to information received from the members of the CMS expert mission, it is becoming clear that two secondary opportunistic pathogens, specifically Pasteurella and Clostridia, are contributing to the rapid and wide-spread die-off. However, the hunt for the fundamental drivers of the mass mortality continues since these bacteria are only lethal to an animal if its immune system is already weakened.
"Experts are working around the clock to investigate the impacts in terms of wildlife health of the relatively high rainfall observed this spring, the composition of the vegetation and other potential trigger factors including a suite of viruses. None of the data analysed to date indicates that rocket fuel is related to the mass die-off. Fresh laboratory results are becoming available every day," said Aline Kühl-Stenzel, terrestrial species officer at the UNEP/CMS Secretariat.
Aerial survey
The aerial survey conducted as part of the national monitoring programme earlier this year estimated that the Betpak-dala population numbered approximately 250,000 animals prior to this mass die-off, which has therefore halved the total population. It is likely that final estimates may extend beyond 120,000 dead saigas since the counting of carcasses by emergency response teams is continuing. It is however becoming clear that the mass die-off has come to an end and that several GPS-collared animals are still alive in herds that were not affected by the mortality event.
Mass mortality events are not unusual for saiga antelopes, with a case occurring as recently as 2010 with 12,000 dead animals. However, the scale of the current event is unprecedented relative to the total population size. Often these mass mortality events occur in the birth period, when saiga females come together in vast herds to all give birth within a peak period of less than one week.
"Saiga antelopes often have twins and populations are able to rebound quickly. Our hope is that if we can control what is driving these mass mortality events as well as tackle the number one threat to saigas - wildlife crime and poaching - populations will be able to recover. Collaboration among all stakeholders is vital. Kazakhstan is leading the way and I look forward to the Range States putting in place strong policies at the CMS Saiga meeting," said Chambers.
