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With the recent bird mortality study in hand, the Minnesota Sports Facilities Authority (MSFA) will give some indication Friday of what it plans to do — if anything — about making U.S. Bank Stadium's glass safer for migrating birds.

Bird conservationists will push for swift action to make the glass less reflective and less transparent so birds can see it more easily.

"Bird-safe retrofit treatments should be applied immediately to the glass on all sides of the stadium in order to protect birds," Jerry Bahls of the Audubon Chapter of Minneapolis said in a statement last week.

The $300,000 academic study, paid for by the Vikings and the MSFA, looked at four migratory seasons beginning in the spring of 2017 and concluding with the 2018 fall season.

Conservationists argued that the study was unnecessary because the effects of clear glass on birds was well-known.

The study — well known to environmentalists and academics — has put the $1.1 billion publicly subsidized stadium into the center of the discussion about urban environmental hazards to birds.

Now comes a time for decisions. The regularly scheduled MSFA meeting Friday will be the first time the public gets a sense of what the stadium authority and the Vikings intend to do with the study: use it or shelve it.

"Our coalition of bird conservation groups is looking forward to learning what concrete actions the Vikings and MSFA will take to address this urgent problem as soon as possible," Bahls said.

Although MSFA Chairman Michael Vekich said the public authority is open to mitigation, he has not said what it would be willing to spend or how quickly it would act.

Realistically, no one expects immediate retrofitting of all the glass on the stadium. Instead, the study said mitigation efforts should be focused on glass near the ground, especially near vegetation, which is reflected in the glass and adds to bird confusion.

The study also recommended reducing nighttime light emissions, something Vekich said the MSFA could work on immediately.

The study, led by associate Prof. Scott Loss at Oklahoma State University, concluded that about 111 birds die at the stadium each year.

Among the buildings in the survey — which did not include every building downtown — the three-year-old stadium ranked third.

Retrofitting turned the Jacob K. Javits Convention Center on the Hudson River in Manhattan from a bird graveyard into an eco-haven.

The reflective glass on the building's giant I.M. Pei-designed facade was replaced with pixilated glass with a fritted pattern that deters birds and led to a drop in bird deaths of around 90%.

Rochelle Olson • 612-673-1747 Twitter: @rochelleolson