ENVIRONMENT

The sudden, mass death of 200,000 saigas provides a dark omen for what might happen to wildlife in a changing world. (The Atlantic)

What other threats do saigas face?

Teachers, scroll down for a quick list of key resources in our Teachers Toolkit.

Discussion Ideas

• The terrific Atlantic article outlines the environmental threats faced by saigas, a critically endangered species of antelope. What are antelope? The links below are photos illustrating the concept—be sure to click!
  • Antelopes are a group of even-toed ungulates. Even-toed ungulates are hoofed animals whose weight is borne by two or four toes. Other even-toed ungulates include pigs, hippos, camels, goats … and cetaceans. (Yes, cetaceans. Whales and dolphins evolved from terrestrial, even-toed ungulates.)
  • Antelopes are Old World animals, meaning they are indigenous to Africa, Europe, and Asia. Saigas are indigenous to the vast Eurasian steppe.
  • Antelopes are a “wastebasket taxon”, which is our new favorite term. “Wastebasket taxon” describes a group of loosely connected species that don’t really fit anywhere else. (Another term for this is “catch-all taxon.”) The most familiar wastebasket taxon is probably “invertebrates,” which is simply “animals without backbones.”
    • Like most wastebasket taxons, antelopes are generally defined by what they’re NOT: cattle, bison, buffalo, sheep, goats, or deer. Other antelope species include impalas, wildebeests, gazelles, and oryxes.
      • There are two subspecies of saiga: the saiga, and the Mongolian saiga. Only male saiga have characteristic thick, ringed horns.
        • That nose: During summer migrations, a saiga’s trunk-like nose helps filter out dust kicked up by the herd and cools the animal’s blood. In the winter it heats up the frigid air before it is taken to the lungs. It may also be used for communication and sexual selection.

• Why did 200,000 saiga antelope suddenly die in 2015?
  • Saiga were killed by infections caused by Pasteurella multocida, a common bacterium that is usually not harmful to saiga.
    • Pasteurella is actually part of a saiga’s microbiome. “It normally lives in the animal’s respiratory tract, but somehow found its way into the animals’ blood, and invaded their livers, kidneys, and spleens. Wherever it went, it produced toxins that destroyed the local cells, causing massive internal bleeding. Blood pooled around their organs, beneath their skin, and around their lungs. The saigas drowned in their own bodily fluids.”
      • Once Pasteurella infects a saiga, it is 100% fatal.

• How to scientists think climate may have contributed to the saiga die-off?
  • Although the connection is still a correlation, “the connection makes sense.”
    • The places where the saigas died were extremely warm and humid.
    • The places where saigas had died in similar, smaller die-offs were also unusually warm and humid.
    • In the lab, rats exposed to Pasteurella are more likely to get infected and die when the humidity is high.
    • Climate—heat and humidity—helps explain the sudden, broad nature of the saiga catastrophe. Climate “would hit all the saiga at once, and influence the bacteria that they all already harbor.”

• How is the saiga die-off influencing the way we might want to think about the impacts of climate change?
  • “People normally envision climate change in terms of droughts, floods, and melting ice caps, but disasters can take different forms. The changing climate could, for example, disrupt the normal relationship between an animal and its microbiome—with catastrophic consequences.”

• Saiga are a critically endangered species. Is there any hope of a population rebound?
  • Yes! They’re hardy critters. Saiga have adapted to a very forbidding ecosystem (the Steppe), one that is prone to droughts and extreme weather.
  • Yes! They have powerful protectors. “All the countries across which the saiga roams recently signed a mini-treaty to protect the antelope, and governments and NGOs are working hard to put an end to poaching.”
    • The signatory range states of the saiga are Kazakhstan, Turkmenistan, Uzbekistan, Mongolia, and Russia.
  • “All it needs is for us to butt out, to not poach it, to not build railway lines across its territory,” says one expert. “Then it does just fine.”

TEACHERS TOOLKIT

The Atlantic: Why Did Two-Thirds of These Weird Antelope Suddenly Drop Dead?

Convention on the Conservation of Migratory Species of Wild Animals: Saiga Antelope

Nat Geo: Endangered Species Categories and Criteria