A massive die-off of over 120,000 endangered saiga antelope in Kazakhstan has scientists worried and puzzled.The die-off represents more than one-third of the global population of the animal.
According to the UN Environment Program, evidence points to a combination of environmental and biological factors, such as a highly contagious disease. Thus far, no animal has survived an infected herd.
“This loss is a huge blow for saiga conservation in Kazakhstan and in the world, given that 90 percent of the global saiga population is found in our country,” vice minister of the Ministry of Agriculture of Kazakhstan, Erlan Nysynbaev, said in a statement. “It is very painful to witness this mass mortality.”
Saiga have a large humped nose that is flexible and inflatable to help it breathe clean air during dusty summers in the high desert plains and warm air during the cold winters. The animals travel in herds of 30 to 40, but during migration, thousands travel together.
The saiga antelope used to be abundant in Russia, Kazakhstan and Mongolia, with a population of over 1 million in the 1970s. Increased poaching in the 1990s following the collapse to the Soviet Union led to a dramatic decline in the species to just 50,000. Since then, conservation efforts helped the animal to recover, particularly in Kazakhstan, which had been home to around 250,000 animals before the most recent die-off.
One potential culprit in the deaths is Pasteurella bacteria, a zoonotic pathogen that causes upper respiratory disease. However, EJ Milner-Gulland, a who heads the Saiga Conservation Alliance, told The Guardian that Paseurella normally only kills weaker animals that are already sick or stressed, so a positive finding of Pasteurella is likely not the whole story. Clostridia bacteria has also been implicated, but like Pasteurella, it normally only kills animals with an already weakened immune system.
Scientists are examining samples from the saigas as well as from the vegetation and soil of the area. Symptoms include foaming at the mouth and diarrhea. Primarily adult females and newly born calves have been affected, Aline Kühl-Stenzel, Terrestrial Species Officer at the Convention on the Conservation of Migratory Species of Wild Animals, said in a statement. That’s because females tend to aggregate in vast herds in mid-May to all give birth together. “It appears that one or several large birth aggregations have been eradicated,” she added.