1000 Migratory Birds Found Dead Overnight in Chicago, USA... What Happened?

Late migration period and adverse weather conditions combined
Mass death likely caused by collision with building featuring continuous windows

In Chicago, USA, over 1,000 migratory birds died en masse overnight after colliding with a large glass building by Lake Michigan.

Over 1,000 dead migratory birds were found at the Lakeside of McCormick Place, a famous trade exhibition center by Lake Michigan, from the night of the 4th to the early morning of the 5th (local time).
[Photo by AP·Yonhap News]

According to the Associated Press on the 10th (local time), the area around the famous trade exhibition hall 'McCormick Place' Lakeside Center by Lake Michigan in Chicago became a graveyard for migratory birds between the night of the 4th and the early morning of the 5th.

David Willard, who has been observing birds near the Lakeside Center for over 40 years, described the horrific scene, saying, "The bodies of about 1,000 songbirds were scattered on the ground, making it look like a carpet was laid out."

Willard, who retired as the bird collection curator at the natural history museum 'Chicago Field Museum,' said, "Usually, 0 to 15 dead birds are found overnight around McCormick Place," but added, "I have observed this area for over 40 years, and this scale is unprecedented."

He continued, "It seems the accident was caused by the peak migratory season, rainy weather, the lighting of the low-level exhibition hall, and the building walls made by joining large glass windows."

Field Museum on-site staff reported, "We collected 964 bird carcasses from 33 species," adding, "This is 700 more than the total number of bird carcasses found around McCormick Place over the past 40 years."

Stan Temple, a wildlife ecology professor at the University of Wisconsin and a bird expert, said that on the night of the accident on the 4th, conditions were met for songbirds to migrate south. He explained, "Small-bodied songbirds tend to migrate at night, flying with the wind to avoid turbulence and predators. They were waiting for north winds, but the unusually warm weather in the Chicago area in September delayed their migration."

Bird experts explained, "Hundreds of millions of birds in the United States collide with building glass windows and die every year. Birds migrating at night navigate by starlight and moonlight, but bright lights from buildings can attract and confuse them, sometimes causing them to crash into windows or circle around the lights until they die from exhaustion."

They added, "It appears the birds were flying south along Lake Michigan and entered the 'maze' of McCormick Place. Due to the rain that day, the birds were flying at a low altitude and noticed the McCormick Place lights."

Anna Pigeon, a bird ecologist at the University of Wisconsin, said, "Collisions of migratory birds with buildings can be easily prevented by dimming building lights at night and designing windows to be visible to birds. Methods such as hanging curtains, painting windows, or applying stickers can also help."

The American Birdwatchers Association has been promoting the 'Lights Out' campaign since 1999, urging buildings to turn off or dim their lights during migratory seasons. Fifty cities in the US and Canada, including Chicago, New York, Boston, San Diego, Dallas, Miami, and Toronto, participate in this campaign.

Additionally, in 2020, the Chicago City Council passed an ordinance mandating bird safety measures for new buildings, although it is not yet enforced.

A McCormick Place spokesperson said, "We participate in the 'Lights Out' campaign," and explained, "Events often run throughout the week, but the principle is to turn off the lights when there are no staff or visitors."

This content was produced with the assistance of AI translation services.