Chicago Takes Dim View of Bird Crashes

The man-made mountain range that looms over Lake Michigan is noticeably dimmer on spring nights, not because of an energy shortage but to keep migratory birds from slamming into Chicago’s clusters of glassy towers.

Each year about 100 million birds across the U.S. are killed crashing into windows or die of exhaustion after becoming mesmerized by lighted buildings, scientists say.

Now more than a dozen Chicago skyscrapers and lakefront buildings have turned off outdoor lights or closed window shades to reduce the toll on migratory birds.