Cities are dangerous for migrating birds. Image: Fatal Light Awareness Program
By Kayla Smith
You hear an unpleasant thud; unsettled and surprised you investigate. The culprit is a bird, dead on arrival.
Like a scene out of an Alfred Hitchcock movie, birds are crashing into windows at alarming rates.
According to a recent report by the University of Toronto, somewhere between 365 million and 988 million birds die annually from window collisions in the U. S. and Canada.
You may say, “Birds crash into windows, who gives a cluck?” Actually, quite a few people do.
The Kalamazoo Nature Center, in Kalamazoo, Michigan, built a preschool with windows that are easier for birds to see.
“The preschool was built at the edge of the woods and we were concerned about bird strikes,” said Sarah Reding, the center’s vice president of conservation stewardship. “The windows seem to be working really well for us.”
Preschoolers watching birds die on impact is a disturbing thought. Like the bird-safe glass, a new bill may save the birds and the preschoolers some trauma.
A member of Congress from Illinois has proposed a bill to bird proof the windows of federal buildings.
“Birds have intrinsic, cultural, and ecological value to humanity,” said U.S. Rep. Mike Quigley, who introduced the Federal Bird-Safe Buildings Act last May. “Migratory birds are not only beautiful creatures eagerly welcomed into millions of Americans’ backyards every year, they help generate billions of dollars annually to the U.S. economy through wildlife watching activities.”
Birding is a $107 billion industry that raises $13 billion in local, state and federal tax revenue, according to the U.S. Fish and Wildlife Service.
Great Lakes cities, such as Chicago and Toronto, are beneath the flyways of birds that migrate between the north and the south, according to the Audubon Society. When tired birds hit the city for the night, tall buildings covered in glass windows morph into a sinister house of mirrors.
“Collisions with glass buildings claim hundreds of millions of bird lives each year in the U.S,” Quigley said. His bill would require bird-safe building materials and design features on federal buildings to mitigate bird deaths.
Toronto residents have advocated for ordinances geared to prevent bird and building collisions with the Fatal Light Awareness Program since the mid-2000s. They require that windows have decals or bird-safe glass, said Michael Mesure, founder of the Fatal Light Awareness Program and co-author of the University of Toronto report.
Volunteers collect dead birds to learn more what’s causing window strikes.
Image: Fatal Light Awareness Program
In 1989, Mesure didn’t believe that bird window collisions were a leading cause of migratory bird death.
He changed his mind when he “saw bird after bird lying dead on the street” during a night walk in Toronto. He started collecting dead birds and recording information on buildings with high body counts. This became the model for 40 citizen science projects across North America that collect and count the avian victims of building strikes.
But even with a pocket full of dead birds, Mesure struggled to get building managers interested in the problem.
“People don’t like change, they have priorities that don’t include saving birds,” he said.
That changed when Cadillac Fairview, one of Canada’s largest commercial property owners, was charged for bird deaths under federal law in 2010.
The company’s Yonge Corporate Center had killed hundreds of migrating birds, due to its highly reflective window surface.
“Experts were able to prove that the reflection of light coming off the building was technically radiation that was killing birds,” Mesure said. “The radiation could be considered a contaminant and the companies could be charged.”
Cadillac Fairfew was acquitted because the court said the company was taking steps to prevent future bird strikes, such as using window decals, according to a report by the defendants in the case, EcoJustice and Ontario Nature.
The judge’s ruling means that the Ontario Ministry of Environment must determine a plan for buildings that are incurring high death rates for migrating birds, EcoJustice lawyer Aaron Koehl said in a news release.
Anti-bird strike ordinances have created a new demand for bird-safe technology, Mesure said.
The Kalamazoo Nature Center knew that decals and fish wire could keep birds away, Reding said. But the group wanted the outside forest to be seen from inside the building.
Birds can see ultra-violet light. Some spiders incorporate UV reflective strands of silk in their webs to make them visible to birds.
Bird-safe glass has an ultraviolet pattern within the glass that is invisible to the human eye, but gives birds a heads up.
“[The bird-safe glass] breaks up the forest for the birds, so they are less likely to fly into the windows, thinking it is forest,” Reding said. “But it’s also great because we can still use our windows for seeing outside”
Stephen Hager, a biology professor at Augusta College, in Rock Island, Illinois, has studied bird strikes for 10 years. There’s still a lot to learn, he said.
Hager is a part of a collaboration of 47 schools ranging from Florida to Nova Scotia to New Mexico that is researching bird strikes.
“It is the largest scale assessment that’s ever been done,” Hager said
The Bird-Window Collisions Project is an online network of student volunteers and researchers who are working to discover the causes of bird strikes.
Hager and his team have developed a standard survey to assess habitat and building features where bird strikes are common.
He suggests limiting the amount and size of windows in buildings and constructing new ones in areas that are already highly developed.
“We are finding there are different collision risks for different species,” he said. “City birds are less likely to die from window strikes, and males are more likely to run into windows than females.
Why is that?
It’s a question that Hager said he hopes to answer.