At least 2,000 snow geese were found dead in Idaho over the weekend, many plummeting to the ground mid-flight, according to local officials.
The birds, which were migrating from Mexico to Alaska, “just fell out of the sky,” a spokesman for the Idaho Department of Fish and Game told Reuters.
The Fish and Game Department believes the birds died of avian cholera, a bacterial disease that can kill wildlife in as little as six hours.
Officials are burning the dead carcasses in hopes that other birds won’t pick up the disease. However, a group of 20 bald eagles has already been spotted near the carcasses and officials say it will be difficult to track the birds to see if they develop the disease.
While avian cholera can be fatal to birds, it poses little threat to humans, officials said.