The new glass-happy U.S. Bank Stadium is back in the news again, as the Audubon Chapter of Minneapolis released a report observing bird mortality and injury at the complex during the fall 2016 migration season.

Audubon and other conservation organizations have brought attention to the potential harm the stadium’s reflective facade poses to birds since its design made the rounds in 2012. And as they have in the past, the sports and general news media have picked up the story, casting another spotlight on the glassy stadium, located within the Mississippi Flyway, a primary bird migration route.

U.S. Bank Stadium (Photo Darb02, Wikimedia)

During an intermittent monitoring period between mid-August and early November, monitors recorded 60 birds killed and another 14 “stunned” due to collision with the building’s glass, according to the study. The report notes that “if the fall 2016 migration season’s total of 60 documented avian deaths were to remain consistent in the future during spring and fall migrations, approximately 360 birds would be killed by the U.S. Bank Stadium in a three-year period.” It adds that “this number significantly underestimates true mortality at the stadium complex, because it does not include birds removed by maintenance staff, security guards, and scavengers.”

As early as 2012, the conservation organizations had called on the Minnesota Sports Facility Authority (MSFA), the managing body of the stadium’s design, construction and operations, to address the bird safety issue by implementing “bird-friendly designs.” However the MSFA cited financial constraints and cost concerns in defending its decision to keep the project as-is.

Last year, the MSFA agreed to contract Audubon Minnesota, as well as the National Audubon Society, University of Minnesota and Oklahoma State University, to conduct a scientific study to monitor bird-glass collisions at the new stadium. The study (which will be more elaborate than the fall report), will begin this spring, with analysis to be released in 2019. The MSFA will then consider possible retrofit options if it deems necessary. The MSFA and the Vikings also committed to participate in Audubon’s “Lights Out” program, joining other Twin Cities buildings in an effort to reduce collision risk by reducing light pollution during spring and fall migration.

Based on the recent fall 2016 study, the Audubon is again calling on the MSFA to implement “specific immediate actions to reduce bird collisions at the stadium.” The report suggests it consider American Bird Conservancy-recommended retrofitting options, including the application of window film; decals and tape; nettings, screens and exterior shades; and awnings and overhangs.

The MSFA is waiting on the larger study results before making any decisions.

“We have a contract with National Audubon and universities that will conduct a study in 2017 and 2018,” says Jenn Hathaway, director of communications with the MSFA. “When we have the final report, we will address the issues we find.”