Saiga antelopes, a bizarre-looking and critically endangered species, are mysteriously dying off in Kazakhstan at an alarming rate, officials said Wednesday, raising fears that a species that has been around since the Ice Age may be on its way to extinction.

In April, Kazakhstan was home to 250,000 saigas. But now, around 40 percent of the Central Asian nation's population of saigas, or 120,000 animals, has died in the past month, setting back conservation efforts.

Saigas were just starting to recover after a major blow about a decade ago, when 95 percent of their population disappeared and dropped their overall numbers to just 50,000 animals.

Kazakhstan, the world's ninth-largest country by area, is home to around 90 percent of the world's population of saigas, recognizable by their lyre-shaped horns and bulbous nose.

"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."

So what could possibly be killing these critically endangered animals? The reason is still unclear, so the Royal Veterinary College (RVC) in Hatfield in the United Kingdom has sent out a team of veterinarians to Kazakhstan to find out. According to these experts, the bacteria Pasteurella and Clostridia are likely behind the mass die-offs.

Pasteurellosis is a bacterial disease that can infect humans and cattle, rabbits, cats and dogs. Its bacteria actually occur naturally in the upper respiratory tract, but are only fatal in animals with weakened immune systems.

Although the evidence points to these pathogens, some environmentalists blame toxic Russian rocket fuel that may have rained down on the plains after rockets exploded during their launch from a Kazakh site.

"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," Erlan Nysynbaev, Vice Minister of the Ministry of Agriculture of Kazakhstan, said in a statement.

Interestingly though, mass mortality events are not unusual for saigas; however, the scale at which it is currently happening is unprecedented given the total population size. Often these mass die-offs occur in the birth period, when saiga females comes together in vast herds to all give birth within a peak period of less than one week.

Still, Kazakh scientists will continue to test soil, air and water to try to solve the mystery of the mass deaths, according to Bagdat Azbayev, chairman of the Agriculture Ministry's forestry and wildlife committee.

"Saiga antelopes often have twins and populations are able to rebound quickly," noted Bradnee Chambers, Executive Secretary of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). "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."

According to Reuters reports, huge herds of saiga once roamed the Earth alongside the famous woolly mammoth and saber-toothed tiger. But when the mammoth and tigers died out, saigas especially became popular for their tasty meat.

There were more than one million saiga in the 1990s, but by 2003 poaching and disease slashed their numbers in Kazakhstan to 21,000, Azbayev said.

Hopefully scientists find the cause and solution to these mysterious die-offs soon, so that saigas may soon continue their road to recovery once again.

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