This story first appeared on People.com.

The vibe outside Minneapolis’ U.S. Bank Stadium, the home of the Vikings since June 2016, has gone from tailgate fun to a scene from The Birds.

According to The Guardian, the gleaming glass that covers the outside of the structure — a structure that cost over $1 billion in taxpayer dollars to build — reflects the sky almost perfectly. Birds flying close to the new stadium are unable to tell the difference between what is glass and what is the great blue yonder, causing them to fly beak-first into the arena’s walls.

Over the fall, conservationists kept track of how this shining stadium affected the local avian population and found 60 birds, dead from crashing into the Vikings’ home, scattered around the glass walls. They found another 14 birds alive, but stunned from collisions.

Three animal protection groups released a report on these findings, claiming the stadium is set to kill at least 360 birds over the next three years. The report also adds that these numbers are an underestimate, because they don’t take into account the uncounted birds removed by the stadium’s staff and others.

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Before U.S. Bank Stadium opened, the Audubon Society warned that the building’s glass would be a devastating “death trap” for birds, and advised the stadium’s owners to add a feature, like an outer-coating to the glass, to help the animals discern between sky and stadium. The owners declined to make any changes.

A new study has been launched to look into the stadium’s effect on the local birds, but it isn’t slated for completion until 2019. Until then, U.S. Bank Stadium is set to remain a confusing and potentially lethal place for birds to be near.