Collisions with buildings take heavy toll on birds

Spring bird migration is in full swing and, sadly, with it comes — as it does every year — a huge toll on the feathered creatures. As they journey to nesting grounds across North America, millions of birds will die from striking tall buildings, communication towers, windows and other man-made structures.

The same is true during fall migration. And migratory birds are not the only victims — year-round residents such as cardinals and bluebirds also suffer heavily from crashing into windows and other barriers.

No one has an exact death toll from this annual carnage, but U.S. Fish and Wildlife Service researchers estimate that it is as high as 950 million birds per year nationwide.

Atlanta is no exception. “Mortality from building collisions is a major threat to our resident and migratory birds,” said Adam Betuel, Atlanta Audubon Society’s director of conservation. “Unfortunately, we don’t know the full extent of the problem.”

The reasons for bird-building collisions are many and varied. In the evening, brightly lit skyscrapers can lure migrating birds searching for navigational cues typically afforded by the moon and stars. Also, most birds (city pigeons are an exception) don’t perceive glass as a barrier and try to fly through it.

To get a handle on Atlanta’s problem — and help develop strategies to mitigate it — Betuel and Atlanta Audubon have kicked off Project Safe Flight Atlanta. They are asking for your help in two ways. One is to help systematically monitor selected areas of the city to look for dead or injured birds. The other is to report any bird-window collisions that you may observe.

To learn more, and how to participate, go to atlantaaudubon.org/project-safe-flight.

In the sky: From David Dundee, Tellus Science Museum astronomer: The Lyrid meteor shower will be visible all next week, reaching a peak of about 15 meteors per hour Thursday night — in the northeast from about 2 a.m. until dawn.

The moon will be full April 22 — the “flower moon.” Mercury is low in the west at dusk. Venus rises out of the east less than an hour before dawn. Mars rises a few hours after sunset. Jupiter is high in the east at dusk and will appear near the moon Sunday night. Saturn rises out of the east just after dark.