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WUWM's Susan Bence reports on Wisconsin environmental issues.

The World's Dangerous For Birds — Fiserv Forum Makes It A Little Safer

Kenny Yoo/Milwaukee Bucks
The Fiserv Forum is "the world's first bird-friendly arena." That's according to the U.S. Green Building Council.

The new Bucks arena is the world's first bird-friendly arena, according to the U.S. Green Building Council. Bryan Lenz, bird collision campaign manager with the American Bird Conservancy, had a lot to do with Fiserv Forum's owner's decision to consider bird safety.

The world is becoming more perilous for birds. They have to contend with cell towers, pesticides and loss of habitat. Cats alone kill 2.4 billion birds every year in the U.S.; another billion die after colliding into buildings.

“We see buildings in [Milwaukee] that kill hundreds of birds each migration season,” says Wisconsin Humane Society Wildlife Director Scott Diehl.

From left: Bryan Lenz and Scott Diehl in front of the Fiserv Forum, which is deemed the world's first bird-friendly arena.

Both Lenz and Diehl say the world can’t afford to lose birds by the billions. Not merely because they’re pleasing to a birdwatcher’s eye, but because birds contribute to balanced ecosystems. Birds help reduce pests, pollinate plants and disperse seeds.

Building With Birds In Mind

To make the Fiserv Forum bird-friendly, Lenz says fabricators embedded thin ceramic patterns, called fritting, in the glass panes. The fritting create lines that are barely visible, “But flying birds can see the pattern and avoid the window,” he says.

Credit Fiserv Forum
Bryan Lenz says birds see the treatment on these windows far better than humans.

Lenz says the patterns — some horizontal, others vertical — must be no more than 2 inches apart, so birds won’t try to fly in between.

"Birds know their wingtip-to-wingtip length within 6 percent accuracy, they found in lab studies, so they know exactly how big a gap they can fly through," he explains.

And the lines don't have to be visible from far away. Lenz says birds have the amazing ability to soar close to an obstacle and “self-correct” their flight pattern.

“The bird only needs to be able to see it within 5 or 10 feet in order to turn around,” Lenz says.

But he says attaining “bird collision deterrence” status requires more than the specially treated glass. Fiserv Forum’s outdoor lighting must cast down, so birds are less likely to be drawn to it.

Credit Susan Bence
On the south side of Fiserv Forum, Bucks human resources employee Tracy Baskin works within its bird-safe doors and windows. Bryan Lenz says this is an example of stronger treatment. "Thinner lines and other patterns can also be effective," he says.

Lenz says he helped negotiate a lights-out policy to better protect birds during spring and fall migration.

“[Lights] don’t need to be off at 8 p.m., but at 5 a.m. they really do. And any time there’s a game or an event, they can stay on until the event is over,” Lenz adds, “and on weekends too, at bar time, it’s meant to be an entertainment district and cut a good profile for the public, so we wrote an exception for 2 a.m. on the weekends."

To maintain the bird-friendly rating from the U.S. Green Building Council, he says the building must be monitored "for three years after construction, which we’re going to be doing in conjunction with the Wisconsin Humane Society."

Diehl, Wisconsin Humane Society says the Fiserv Forum will be added to the buildings his volunteers monitor. 

"I think of this being a monumental moment," says Scott Diehl, of the Wisconsin Humane Society.

"Our WINGS volunteers go out in the peak migration times in May and also in September and October to monitor around various buildings in downtown Milwaukee looking for birds that have collided with windows — living or dead,” Diehl says.

Part of the problem, he says, is that more and more buildings are incorporating more glass into their design. That trend is intensifying the risk to birds.

But Diehl calls Fiserv Forum a game changer.

"I think of this being a monumental moment. This company, the Milwaukee Bucks, making this a bird-safe building," he says.

Education Is Important

In order to pull off the bird-saving Fiserv Forum construction, Lenz spent three years nudging the arena owners and designers, being, as he put it, “a likable pain in the ...”.

Kansas City, Mo.-based architect Heather Stewart is one of the people who listened. She was part of the arena's design team.

“The cost of this is inconsequential. It just a little more thought to make sure the design was implemented so it achieved the bird safety we were going for,” Stewart says.

Credit Michael Stubblefield
The American Robin is Wisconsin's state bird and a member of the thrush family. Thrushes, like Wood Thrush and Swainson's Thrush, are frequent victims of glass collisions.

But Stewart says until Lenz showed up — and kept showing up — her firm didn’t know the strategic treatment of glass could make the difference between a bird colliding into it or not.

Her team designs projects around the world. Stewart says the Fiserv Forum model is influencing some of them.

“I can’t really mention any names — but this will definitely be thought of as we move into other project designs,” Stewart says.

Lenz isn't resting on his laurels with the completion of the arena project. He's also trying to teach people about the dangers birds face throughout the built environment.

Of the estimated 1 billion birds that collide into U.S. buildings every year, he says, “46 percent are at homes and residences — so the one to 10 you might have at the average house will add up across the country.”

That leaves lots of room for public education, Lenz says. The American Bird Conservatory offers education on stopping bird strikes, including hitting windows.

This January 18 Lake Effect feature includes Bryan Lenz and Scott Diehl assessing how bird-safe reporter Susan Bence's home is. The results were not good.

What You Can Do

To make your windows bird-safe, Lenz says to follow a 2-by-2-inch rule. “Pattern elements should have no more than 2 inches between them horizontally or vertically for a pattern to be highly effective,” he explains.

He says, the pattern should be at least 1/8 inches in diameter/width and on the outside of the window.

“The patterns should be on the outside of the window whenever possible. When glass is highly reflective the reflection erases patterns on the inside of the glass,” Lenz says.

The American Bird Conservancy offers more window treatment options, and the Wisconsin Humane Society offers tips on what to do if you find a bird that’s collided with a window.

Another bird-safe consideration: that cats can be dangerous for birds' health. Don’t worry cat owners, there are tips on what you can do to help.

Have an environmental question you'd like WUWM's Susan Bence to investigate? Submit below.


Susan is WUWM's environmental reporter.
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