How a common bacteria suddenly killed 200,000 long-nosed antelope

Now that's a honker and a half.

Image credit: Getty

Published: June 8, 2024 at 3:00 pm

A saiga antelope walks into a bar. “Why the long face?” asks the bartender. “Because my long nose helps to filter out dust during the summer months, and warms the cold air I breathe in during the winter,” replies the saiga. “Also, lady saigas dig a big hooter.” 

It’s not much of a punchline, but nor is the saiga’s bloated, double-barrelled proboscis even the weirdest thing about it. 

The weirdest thing about the saiga antelope is what happened in May 2015. It was their breeding season and vast herds of saiga antelope were just hanging around, chewing the cud, in the grasslands of central Kazakhstan. 

Mothers were giving birth to twins, and sometimes singletons. Then, one by one, the animals started to wobble, fall down and die. Adults and youngsters were affected. 


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Over the space of a few short weeks, around 200,000 saiga – equivalent to 60 per cent of the global population – went hoof up. 

Saiga have lived in the remote Eurasian Steppe grasslands of central Asia for thousands of years. In the 19th century, numbers declined when the German Shepherd-sized herbivores were poached for their distinctive ridged horns.

Conservationists spent decades bringing them back from the brink, so when the mass die-off happened, they were both devastated and mystified. Autopsies were performed, and blood and tissue samples were sent for analysis. 

Viruses were mooted as a possible cause, as was poisoning from the toxic rocket fuel used at Kazakhstan’s Baikonur Cosmodrome. 

In the end, the antelope were found to be infected with a bacterium called Pasteurella multocida

That, in itself, was not unusual. The microorganism is often found in healthy animals, including antelope, cattle and goats, where it’s usually harmless. Something must have caused the bacterium to multiply out of control and seep into the antelopes’ bloodstream, which led to blood poisoning and internal bleeding. 

Two smaller mass die-offs happened in Kazakhstan back in the 1980s. So, researchers analysed historical data and found that both events were preceded by an unusually hot and humid patch of weather. 

This, they suspect, created the perfect conditions for the bacteria to thrive, and caused the previous die-offs. Now, the researchers are concerned that similar weather conditions caused the 2015 event and that mass die-offs like this could become more common in a warming world. 

Meanwhile, the hardy saiga have bounced back. Under the watchful eye of the conservationists who care for them, there are now an estimated two million or so saiga roaming the grasslands of Kazakhstan, Russia and Uzbekistan, as well as a related subspecies that lives in Mongolia. 

Anti-poaching and law enforcement measures, habitat protection, population monitoring and local community engagement have all paid off. 

In December 2023, the International Union for Conservation of Nature downgraded the saiga from ‘Critically Endangered’ to ‘Near Threatened’. But researchers caution that such a remarkable recovery doesn’t mean the species is bulletproof. 

Much like so many species, the future of the saiga antelope remains uncertain.

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