A stunning skyline like Chicago’s can be a death trap for migratory birds.
Thousands of birds die each year after crashing into the glass windows of skyscrapers, and tall buildings can interrupt birds’ behavior in other harmful ways as well.
Every year since 2010, Rep. Mike Quigley has introduced legislation to help stem the tide by forcing changes in building codes. This time, he’s teamed up with Alderman Brian Hopkins.
Morning Shift checks in with local birding experts to get their thoughts on the problem and the solution proposed by lawmakers.
What issues do skyscrapers pose to migratory birds?
Annette Prince: Bright lights and urban lighting that has increased so much in recent years is a bad attraction for them ... the glass that’s in all of our building design is very hazardous for them because it’s reflective and transparent in ways that confuse them, that they will strike the glass either thinking they can pass through an empty space … or they see a false reflection that will cause them to run into what they think is a real tree.
Jenn White: At white time of year is this issue most acute?
Prince: The spring and fall migration seasons are the worst times of year when we have these visiting birds. When you think about it, they’re living in a tropical rainforest area. In the winter time, and they’re up in the northern forest, these birds don’t have any experience with the urban neighborhoods and the types of structures and materials that they have to encounter and survive while they’re passing through our area.
Scientific studies show a drop in bird populations
Judy Pollock: Scientists are finding that birds are attracted to cities so that they’re no longer migrating in a more broad front across the city but they’re actually being drawn into the cities…
White: Do we know why?
Pollock: The lights draw them in. And when they get here, as Annette said, they’re crashing into the windows. And they’re finding that it’s actually impacting bird populations where they’re finding that numbers of birds are dropping in some cities 5 percent a year.
White: Are there any certain species of birds that are being more impacted than others?
Prince: The white-throated sparrow is considered to be a bird that is most apt to come in through cities. It’s certainly the number-one bird that we find when we’re downtown and monitoring for the dead and injured birds. Ovenbirds, which are a kind of warbler, are found with high frequency.
On legislation, local efforts to help protect birds
White: We have this bill from congressman Quigley. That’s federal legislation that would apply to many public buildings across the U.S. But then we have a very similar bill from alderman Brian Hopkins that would apply more widely here in Chicago. Walk us through some of the measures in that city council bill that you think would have the greatest impact on protecting birds.
Pollock: What the measures would actually do is that they would divide a building up into the lower part of the building, where there are trees and birds are more likely to be, and then the upper stories. And for those lower stories, almost all of the glass needs to be treated in some way. A bird will try to fly through an opening that is two inches tall and four inches wide, so there needs to be some sort of treatment on that glass that creates openings that are smaller than that.
White: If this bill passes, will these rules apply retroactively to buildings or just to buildings going forward?
Pollock: No, it’s only new buildings and major renovations. And it also doesn’t apply to smaller residential buildings.
White: What do you make of the efforts (of building owners and associations) that have been made so far?
Prince: The efforts that have been made so far are great. The Lights Out program — Our Chicago building owners really cooperate with that, but they’re definitely not enough. The research is incontrovertible that it’s affecting a many species populations. And these are birds that are already under a lot of threat.
This interview has been edited for clarity and brevity. Click play to hear the full conversation.
GUESTS: Judy Pollock, vice president at Chicago Audubon Society
Annette Prince, director of the Chicago Bird Collision Monitors
LEARN MORE: Spectacular Skylines Can Also Be Bird Killers. Here’s How A Proposed Chicago Ordinance Is Trying To Help. (Chicago Tribune 2/11/19)