Millions of birds are currently flying through the Great Plains and the Midwest as they make their way toward their spring breeding sites, and many of those birds are flying through Illinois this week.
According to the latest updates from Birdcast, a service managed by Colorado State University and the Cornell Lab of Ornithology, more than 24.5 million birds were estimated to be in the skies over Illinois at approximately 11 p.m. Sunday.
Of those, nearly 7.2 million birds crossed through the state on their way to their spring breeding grounds in Wisconsin and Canada.
Alerts were issued by the universities for residents to take steps to protect birds, with high volumes of migration still anticipated Monday and Tuesday nights.
Monday night will be especially busy, with more than 400 million birds expected to take flight across the eastern United States:
Nearly 400 million birds are also expected to be on the move Tuesday night and into Wednesday morning:
The one complicating factor in Illinois could be the threat of rain, which will cause birds to remain grounded or to limit their overnight travel, according to the schools.
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Since the start of the spring migration, an estimated 320 million birds have crossed Illinois, above the state’s historic average.
As the spring migration has picked up, various species of warblers are the primary travelers over Illinois at this time of year, including the Yellow Warbler, the Nashville Warbler, the Black-and-white Warbler and the Black-Throated Green Warbler.
Baltimore Orioles are also flying through the state in increasing numbers, with bird watchers reporting sightings at various points throughout Illinois.
According to Birdcast, birds typically begin their migratory flights 30-to-45 minutes after sunset each night, taking advantage of cooler weather and decreased winds as they make their way northward.
Residents are asked to turn off all unnecessary exterior lights between 11 p.m. and 6 a.m. on nights when bird activity is high, as the lights can disorient birds and cause them to crash into buildings.
Residents are also being asked to leave their cats indoors, as the animals can attack birds as they rest on the ground during their long journey northward.
