Millions of birds taking flight Saturday night over Minnesota

While most Minnesotans settle in for the night, the skies above the state are expected to come alive with one of nature's great autumn migrations.

Look up, Minnesota!

The newest BirdCast forecast for Saturday night predicts roughly 321 million birds will be migrating across the continental United States. The forecast map shows a broad band of elevated migration stretching across the Upper Midwest, including Minnesota, as birds begin their seasonal journey south.

The migration is largely invisible from the ground. More than 80 percent of North America's migratory bird species travel at night, according to BirdCast, using the darkness to make long-distance journeys while taking advantage of cooler temperatures and, often, favorable winds.

For Minnesotans, that means the sky overhead Saturday night could be considerably busier than it appears. Birds typically begin taking off about 30 to 45 minutes after sunset, with the largest numbers often in the air two to three hours later.

The numbers are estimates generated from weather-radar observations and migration models, rather than a literal count of individual birds. BirdCast uses the nation's weather-surveillance radar network to detect birds moving through the atmosphere and forecast where migration will be most intense.

How to help the birds

There’s also a simple way for Minnesotans to help: turn off unnecessary outdoor lights tonight. Artificial light can attract and disorient migrating birds, increasing the risk of collisions with buildings and windows.

So while Minnesota’s night sky may look quiet, it could be anything but. High above the rooftops, lakes and forests, hundreds of thousands, potentially millions, of wings could be moving south through the darkness.