Last summer a cute little bird smacked into our patio door. It stood stunned long enough for me to get this closeup.
I see lots of cardinals (my favorite!), finches, sparrows and other backyard birds all year round. Others—robins and the like—come only when the weather warms up. However, I don’t recall ever seeing one in pretty pastels of brown and yellow. This beautifully colored creature does not pop out for me as one of the 23 most common birds in Minnesota. What could it be? Google Lens provides a clue by identifying it as a warbler. Along this line, based on what’s pictured on internet (even narrowed to warblers, many appearing similar), I’m going with this being a female (juvenile?) common yellowthroat. Do you agree?
Happily, this cute little yellow-throated bird flew off soon after its stunning encounter with our house and never came back to knock on our door. However, from time to time a bright-red male cardinal takes issue with its rival staring back from our bay windows. I’ve tried to ward these aggressors off by taping CDs shiny-side-out to the middle of the glass. However, that never works. Now, thanks to a heads-up from New York Times,* I know why: This new study by College of William & Mary biologists shows that window films increase avoidance of collisions by birds but only when applied externally.
“Bird collisions with windows kill more than a billion birds per year.”
Professor John Swaddle, lead scientist of first experimental study to compare the effectiveness of window films when applied to internal versus external surfaces of double-glazed windows
The researchers randomly divided 72 zebra finches into 4 groups via a two-factor, two-level factorial that varied type of film—BirdShades (not commercially available yet) vs Haverkamp—and location on the glass surface—interior vs exterior. No worries—their ingenious flight-testing facility featured a net that prevented window-bound birds from head-on collision.
By the way, in this interview by W&M News (check out the picture of his student showing the “proper technique for holding a zebra finch”), Swaddle says that “silhouettes of animals or birds don’t tend to work in part because they’re generally too spaced out.” So, when our windows again come under attack by angry birds, I will use many CDs (putting a plentiful pile of unused and obsolete media to good use)—not just one—and duct tape them to the outside—not the inside. I just hope that the neighbors don’t complain about the blast of solar radiation going back their way.
*“Those Window Stickers to Prevent Bird Strikes? There’s a Catch.”, Catrin Einhorn, Feb. 2, 2023 (Updated Feb. 7)