There were very few – in fact, no – human visitors to the museum at John James Audubon State Park in Henderson Kentucky the other day. This wasn’t surprising given that the particular day we chose was bitter cold, snowy, and windy. There were plenty of avian visitors flocking to the feeders outside the observation window. Titmice, Goldfinches, Downy Woodpeckers, Cardinals, and White-breasted Nuthatches were eagerly gobbling up the seed.
It was an average feeder assembly and not one worth reporting other than the presence of one species – at least for a Northerner like me. Several Chickadees flitted about this scene and dangled from the wire mesh at the bottom of the suet feeder. It occurred to me that even though these were “Black-capped” Chickadees they weren’t actually Black-capped Chickadees but Carolina Chickadees. South of the Ohio River (the actual line spans across southern Indiana/Illinois) these birds replace their northern cousins. If it weren’t for this stark geographical fact, it would be extremely hard for the average person to tell the two apart. Being average, I had to rely on the geography test.
There is a real physical difference between the two. Carolina Chickadees are slightly smaller than Black-caps, and have a neater edging to their bibs. In truth, these minor traits are far from convincing or observable for that matter. Even the birds themselves can’t quite tell who is who and will hybridize along a narrow strip of territory where their borders meet. Geography makes this an elementary question, my dear Watson, but the aural test works if you live in the hybrid zone (or don’t know where you are).
Carolina Chickadees have a four note call that sounds something like “fee be fee bay” or “Phoebe Baby”. Black-caps employ a simpler two note call. If the on-line literature is to be believed, the hybrid birds utter a three note call!
I truth, the real reason I bring this topic up has to do with another question of geography. The Carolina Chickadee pictured above was hanging from the feeder at the John James Audubon museum. This great naturalist/artist once lived in Henderson, Kentucky and the park and museum is dedicated to his memory. It is a small bit of poetic justice that my Chickadee encounter took place here. Mr. Audubon was responsible for providing the first scientific description of the Carolina Chickadee and his name will be forever attached to the bird.
Audubon encountered this diminutive bird while in South Carolina in 1820 and named it the Carolina Titmouse. Today the scientific name has morphed into Poecile carolinensis (Audubon 1820).
I met J.J. later in the day at Henderson’s city park but didn’t get a chance to complement him on his discovery. He was studying a White Pelican at the time and it was too dang cold to stand around and wait.