PORTLAND, OR — From Oregon City to Portland, Gresham to Hillsboro, more than 14,000 migrating birds are expected over the area Tuesday night.

Portland Audubon would like people to turn off outside lights and draw blinds and shades in an effort to help the birds navigate the night sky.

City lights make it harder for birds to see the moon and stars by which they orient themselves, the society said.

"Once trapped in the windowed maze of the city, birds either hit buildings directly or circle them until they collapse from exhaustion,"the society said on social media.

Using data from Colorado State University's Aeroeco Lab, the society estimated that around 14,200 migrating birds will be in the area. While the night sky might make it seem like they're not there, they will be, the society said.

The society has been working with the Portland City Council on regulations that would limit light pollution.

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