For the Birds Radio Program: Thunderstorms
How do birds survive dangerous thunderstorms?
When the Statue of Liberty asked to send her the homeless, tempest-tossed, I’m not sure she was thinking about birds. But the many storm systems that rip through the continent leave a lot of storm-tossed birds in their wake. People have called me about bitterns, shorebirds, and flickers that they’ve found after thunderstorms, some with broken wings and other injuries. And many of them have asked me whether it’s normal for birds to be injured in storms.
Yes it is. The rain itself isn’t usually too harmful except during the nesting season. Baby birds sometimes get so wet that they die of hypothermia. American Goldfinch nestlings sometimes drown right in their nest–the thistle-down lining makes the nest as waterproof as a teacup.
Hailstones probably take a much bigger toll than rain. In 1938, a biologist discovered two dead California Condors that had apparently been pelted by hailstones while eating a horse carcass. In July 1953, two hailstorms in Alberta, Canada, killed fully 150,000 ducks and geese, and countless other birds too small too document. In the autumn of 1960, thousands of Sandhill Cranes were killed by storms in New Mexico. And again, even more small birds were killed.
Lightning takes a toll, too. More than one tree struck down by lightning has been found to contain dead woodpeckers, owls, or other birds. In the early 1980s, John James Audubon saw two nighthawks struck down by lightning in Florida. In 1941, an ornithologist watched four Double-crested Cormorants fall out of a flock after a flash of lightning. All four were dead, though their feathers were not scorched. In another storm, more than 50 Snow Geese were blasted out of a large flock by a single lightning streak. At least one goose was badly burned, but autopsies revealed that many of the others died from the impact when they fell to the ground. Two years earlier, in 1939, another ornithologist watched 34 pelicans get blasted out of the sky. And both Bald Eagles and Ospreys have been killed by lightning when sitting atop their nests in tall trees during storms.
Storms during migration kill many more birds than most natural phenomena. People often find dead birds littering beaches. Countless other birds are eaten by fish or turtles before they ever wash ashore. And hurricanes take an incredible toll. Hurricane Hugo destroyed hundreds of thousands of birds during its savage spree, including a significant percent of the last remaining Red-cockaded Woodpecker.s