Why are Dead Geese Falling From the Sky in Idaho?

Over 2,000 birds have been felled by fast-moving avian cholera

Mike Hollingshead/Corbis

Every year, thousands of snow geese make their way to northern Alaska to nest. But this year, at least 2,000 birds didn’t make it—instead, they fell to the ground in eastern Idaho.

Reuters reports that “dozens” of volunteers and wildlife specialists from the Idaho Department of Fish and Game spent their weekend recovering the carcasses of dead snow geese that “just fell out of the sky” on their northbound trip. The culprit: avian cholera, which the National Wildlife Health Center characterizes as a bacterial disease “so rapid that birds literally fall out of the sky or die while eating with no previous signs of disease.”

Though avian cholera doesn’t threaten humans, it can endanger other wildlife. Reuters notes that up to 20 bald eagles were seen near the carcasses, which were eventually incinerated by workers. However, a spokesman for the Iowa Department of Fish and Game told Reuters that “a lengthy incubation period makes it unclear if eagles were infected and would carry the ailment area.”

Only time will tell if bald eagles will be the next species to fall from the sky en masse. Until then, here’s a comforting thought—it’s not that unusual for large numbers of animals (winged and otherwise) to tumble toward the earth.

Last year, up to 100,000 dead bats were dumped over Queensland, Australia, apparent victims of a summer heat wave. And lest you think flying creatures or dead ones have a monopoly on falls, consider this: live animals as diverse as frogs, snails and eels have rained from the sky over the course of history.

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