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Is this for real? In Alan Weisman's fabulous 2007 book The World Without Us (ISBN 13 978-0-312-34729-1) he describes how, on the morning of January 23rd 1998, nearly 10,000 migratory Lapland longspurs were found frozen on the ground in Kansas. Apparently they had crashed into a cluster of lighted radio towers the night before.

Was this an isolated case of bird kill? Some scientists contend that as many as 200 million birds fatally collide every year with lighted towers, and that's in the US alone. Is that possible?

In recent years, the explosive growth of cellphones has added at least 175,000 more lighted towers to the landscape. If observers are correct, that could bring the toll of dead birds due to tower crashes to an arresting half a billion creatures annually.

Moonlight Migrations

Some scientists say migrating birds that fly at night, and birds that use moonlight to navigate by, are especially susceptible to death-by-tower. The Christian Science Monitor reported that as many as 50 million birds are killed annually in US cell-tower collisions. Ornithologists studying this problem are counting vireos, hummingbirds, warblers, sparrows, finches, ovenbirds, thrushes, ducks, gulls, plovers, owls, hawks, and even rare red-cockaded woodpeckers amongst the dead.

It’s interesting that the United States Fish and Wildlife Service is now addressing this problem. The Service notes that more than 77,000 transmission towers in the US now exceed 200 feet in height, and therefore require safety lighting. The number of registered towers is estimated to be about a third lower than the actual number of existing towers, as many towers aren't registered with the Federal Communications Commission.

"This has been an issue for fifty years, though," claims Joelle Gehring, a biologist with the Michigan Natural Features Inventory. "But we now see industry and conservation groups coming together to resolve it."

In an article in the Journal of Ecological Applications, Gehring revealed that steady red lights were the biggest attraction for birds, especially in cloudy weather. When red lights were removed, bird deaths fell by 71%. "That finding was a major breakthrough," says Albert Manville, senior wildlife biologist with the US Fish and Wildlife Service.

Power Lines And Glass

High-tension cross-country power lines and towers may also be a problem. Weisman notes there's enough wire in the US power grid to reach to the moon and back more than once. Some scientists say wires and towers are inflicting a staggering toll on flying birds.

Glass may also be a problem for our feathered friends. One ornithologist first estimated that 100 million birds die from crashes with plate glass on buildings, both clear and reflective, but that researcher has since updated the estimate to one billion bird deaths annually. Collisions with plate glass windows occur when birds don't see the window, or see sky or habitat reflected in the glass. Fatal collisions occur when birds see their reflections, too, mistaking what they see as a territorial threat from another bird.

There are agencies, companies, and organizations addressing this problem. Some cities with illuminated buildings that attract migrating birds have initiated Lights-Out campaigns. These crusades have been implemented in New York, Chicago, and Toronto. A study by ornithologists at the Field Museum of Chicago found that turning off building lights, especially during migration season, reduced bird deaths by more than 80%. Here is more information about bird collisions.

What’s your opinion about birds and towers? Write me at amm at en-genius dot net, or post your comments on our blog.