Hailstorm kills thousands of birds in Montana

A strong hailstorm killed or injured at least 11,000 birds in Montana, United States, on 11 August.

The incident happened at the Big Lake Wildlife Management Area, officials said, with the storm striking the area approximately 35 miles west of Billings with 70 mph winds and hail up to two inches wide. As well as the avian casualties, there were reports of smashed windows, vehicle damage and shredded trees.

Some 11,000 birds were killed or brought down by the storm (Montana Fish, Wildlife and Parks / Twitter).

Biologists with Montana Fish, Wildlife and Parks found dead ducks and shorebirds with broken wings, smashed skulls, internal damage and other injuries, the agency said in a statement. Around a quarter of the birds at the lake were killed or injured, and some of the injured birds were not expected to survive, biologist Justin Paugh explained.

Some 5 per cent of ducks and 30 to 40 per cent of pelicans and Double-crested Cormorants "show some sign of injury or impaired movement." The agency said it was monitoring the lake because of concern the rotting bird carcasses could cause botulism or other diseases that could harm the surviving birds.

Most of the dead birds have blown on shore, according to the statement. "On a positive note," Paugh said, "the lake is still covered with waterfowl that are alive and healthy. Life will go on."

Big Lake Wildlife Management Area is a nesting area for dozens of species of ducks, Canada geese, double-crested cormorants, shorebirds, gulls, pelicans and other waterfowl, according to the state's FWP. The shallow lake currently covers about 4,000 acres because of the wet spring weather, it said.

Hailstorms are not unusual in Montana. Shawn Palmquist, a meteorologist at the National Weather Service in Billings, explained: "This isn't uncommon for us, but it normally happens in June.

"June is when we have lower freezing levels and can get hail. August is typically more a wind month."