"Irruption" phenomenon causes some bird species to return to Michigan
Heading into winter, Michigan bird watchers can expect to see some uncommon birds for this time of year.
The phenomenon is called an “irruption,” and is extending the bird watching season in the Midwest, as birds return from the Northeast and parts of Canada due to a lack of food.
This gives Michiganders the opportunity to attract these birds into their own backyard and birdfeeders, or they might encounter them on a winter walk.
Juliet Berger is an ornithologist for the city of Ann Arbor. She said irruptions are not cause for alarm, but they are cause for excitement for bird watchers. Irruptions are a normal byproduct of population influxes and changes in food supply from year to year.
“In years when there's no food where they live year round, they come down here or farther south. So it's a great opportunity to see things like evening grosbeaks, which are being seen in Washtenaw County.”
Male evening grosbeaks can be identified by their yellow underside and backs, while females are brown with black wings with white patches. Birds are returning to Michigan due to a lack of food in their normal year-round habitats, so they will be likely to visit a bird feeder. Evening grosbeaks prefer black oil sunflower seeds on a platform bird feeder.
Berger reminds those hopeful of spotting these seasonal rarities, to clean their bird feeders frequently to prevent the spread of disease.