I have written about the endangered saiga antelope before. See Teetering On The Brink But Still Cause For Hope (that's sarcasm in the title). And now there is Kazakhstan’s ecological mystery: Why have over 100,000 saiga antelopes died in just a few weeks? (Washington Post, May 29, 2015)
As a species, saiga antelopes have endured a lot. They once roamed the Earth with Wooly Mammoths during the last Ice Age and but were almost driven to extinction by a loss of habitat and hunting during the late-20th century. Now the distinctive animals, easily distinguished by their large noses and prized for their meat and horns, are considered an endangered species and protected by the government of Kazakhstan.Around May 10, however, they began dying en masse. Now, in just a few weeks, vast numbers of the species been found dead – Kazakhstan officials have said that almost 121,000 carcasses have been counted, according to Reuters, a number officials from the United Nations Environment Program (UNEP) have confirmed.
For an endangered species, this is dramatic, if not catastrophic. Kazakhstan's has around 90 percent of the world's saiga population, which was estimated to be around 250,000 before the deaths began. Experts are clearly shocked. "It is very painful to witness this mass mortality," Erlan Nysynbaev, vice minister of the Ministry of Agriculture of Kazakhstan, said.
"It's very dramatic and traumatic, with 100 per cent mortality," Richard Kock of the Royal Veterinary College told the New Scientist this week from Kazakhstan. "I know of no example in history with this level of mortality, killing all the animals and all the calves," Kock added, noting that the animals die after respiratory problems and extreme diarrhea.
Nobody knows why these antelopes are dropping dead left and right.
On Thursday, researchers working with the UNEP say that two pathogens, Pasteurella and Clostridia, appeared to be contributing to the die off, but that the animals appear to have already had their immune systems weakened by another unknown factor.
Whatever is causing the deaths, experts are fearing the worst. "The death of the saiga antelope is a huge tragedy," zoology scientist Bibigul Sarsenova told Reuters. "Should this happen again next year, they may simply disappear." But the hope is that if the deaths can be controlled or stopped, the animals can bounce back, again.
To be clear, the bacteria Pasteurella and Clostridia are always present in the saiga population, and may take down animals whose immune systems are compromised, so that is the proximate cause. The underlying cause of the die-off is some disease and/or environmental Factor X which nobody has been able to identify.
The human-caused aspect here, regardless of the identity of Factor X, is that when a species population shrinks down to a certain level, then, depending on the species in question, that species becomes increasingly vulnerable to endemic population (or total) extinction caused by one-off events like the one killing off the saiga. And of course it may turn out that Factor X is also human-caused due to some simple or complex chain of events.
Finally, there is this from UNEP (linked-in above).
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.
So, they are still counting the dead, though it is "becoming clear" that the die-off is coming to an end.
That's the Good News.
So sad.
Even sadder, of course, is that this is not the first such story, nor will it be the last.
Posted by: Brian | 05/29/2015 at 03:08 PM