We were visiting family in Illinois, and though we weren't there for the birds, we're always on the lookout for them. Sitting in the house with the windows open on an unseasonably cool late June day in central Illinois, I heard calls that were characteristically dove-like. They were different though - not like the low "whooo-what, whooo-whooo-whooo" of our Mourning Doves back home.
I had seen Mourning Doves in the yard and knew that they are the most prevalent dove in the Midwest, so without a field guide in hand, I thought maybe I was hearing a regional variation of the Mourning Dove call. They say that a Tufted Titmouse from the east sounds different than the tuftie from the middle of the country, why wouldn't doves have dialects as well?
But when I got up to look out the window to investigate, I saw a larger and lighter colored dove than what I'm used to seeing. And it had a black crescent on its neck, meaning it was a Eurasian Collared Dove!
The Eurasian Collared Dove is native to Eurasia, and is a recent North American colonizer from the Caribbean. It is spreading rapidly; even the range map I initially checked out didn't show it all throughout central Illinois.
I started paying more attention, and could hear its now distinctive and repetitive call throughout all the yards in the area.
Even backyard birders can discover different (and maybe new) species where they aren't necessarily expected. Be ready, and listen and look for differences, and you might experience a bird pushing the limits of its range!