Millions of birds are flying over our heads every night during spring migration

While you're sleeping, hundreds of millions of birds are flying overhead each night to get back home from their winter vacations.

These are the peak weeks for the spring bird migration, and our region is on one of the busiest paths along the Mississippi River flyway.

For example, the website Birdcast says that just tonight, 361 million birds are predicted to be in the air as of 3 hours after sunset. Tonight's busiest paths will be along the Texas coast, and from our Quad State region then along the west side of the Mississippi River through Missouri and Iowa.

Daytime migration is occurring, too. Birdcast's live map shows nearly 20 million birds in the air today, again busiest over Texas and Missouri.

In general, bird movement in Kentucky, Illinois and Tennessee really picked up during the last week of April, and will not taper off until mid-May as migratory birds fly past from as far away as Central and South America. The process will reverse itself in the fall.

We're most familiar with the classic sight of geese winging their way north or south in their classic "V" formation. But more than half of North America's 650 species also go on the move every year. Even tiny hummingbirds cover thousands of miles back and forth to Mexico and Central America from the entire eastern half of America and Canada. Hummingbird aficionados in western Kentucky were already spotting their first visitors in late March and early April.

The accuracy of bird navigation is astounding, and not completely understood. Birds often travel the same course year after year with little deviation. Birds can get compass information from the sun, the stars, and by sensing the earth’s magnetic field. Somehow they can find their winter home despite never having seen it before, and return the following spring to where they were born.

In recent decades, long-distant migrants have been facing a growing threat from communication towers and tall buildings. Many species are attracted and disoriented by the lights of tall buildings, and millions are killed each year in collisions with them. Within the past decade, many cities have enacted "lights out" initiatives to protect the birds and save electricity and money at the same time. The St. Louis Arch turns out its lights each May and September during migratory periods, along with other taller structures.


MAP - Forecast of bird migration over America on May 6 (Birdcast..info)