MINNEAPOLIS — The Audubon Society of Minnesota is asking the Minnesota Vikings to do more to protect birds from fatal collisions with the massive glass walls of its new stadium.

The team recently told the society it wouldn’t use glazing techniques and lighting that could warn birds away from the building.

The Vikings and the authority overseeing the stadium told Audubon last year they would turn off stadium lights at night to lower risk to birds. But Audubon says that’s only a partial solution. They say using safer glass wouldn’t cost that much more for the billion-dollar stadium.

The Minnesota Sports Facilities Authority says it doesn’t have the budget to include the $1.1 million needed for bird-safe glass. A Vikings spokesman didn’t immediately return a call.