Field Trips

Killer Windows

August 3, 2017 — An unusual hummingbird flew into the frame of my viewfinder last weekend, and landed on a perch to drink. She was a stand-out amidst the cloud of feisty Broad-tailed and Rufous Hummingbirds who were dog-fighting like Second World War pilots for places at the feeder. Her angled beak looked broken, but my soft heart wanted to believe she was a new species.

We were at Sipe Mountain Wildlife Area outside of Eager, AZ, for the High Country Hummers Festival, an annual event sponsored by Arizona Fish and Game. The day was soggy: the monsoon brought in high humidity, jarring crashes of thunder and lightning and heavy, straight-down rain. Visitors sheltered on the porch of the headquarters building, and the birds hunkered down in the trees. During breaks in the rain, hummingbirds rushed the feeders hanging from the eaves.

I queued up my shot of the unusual bird and walked inside to look for Sheri Williamson. Sheri is author of the Peterson’s hummingbird field guide, and she and her husband band hummingbirds at the festival every year. I showed her my picture and asked her what she thought.

Unfortunately, she said this was a female Broad-tailed – not a new-to-me species with an exotic beak. Sheri said the bird had probably broken its beak flying into a window. She had been watching it for a couple days, and she said that the bird was probably not faring well in the competition for nectar. My husband Steve commented that the bird looked plump, but Sheri replied that hummingbirds fluff their feathers when ill.

The break in the beak undoubtedly affects the bird’s ability to drink nectar. Hummingbird tongues are complex structures that flick 15 times per second. The tip splays out like one of those grabber gadgets, and pushes the nectar into the bird’s throat like a pump. A bend in the bill can’t be beneficial. But the injury must also profoundly impact her ability to catch insects. Hummingbirds derive protein and minerals by picking tiny insects off leaves and branches (called gleaning), or by catching them midair (hawking). A malfunctioning beak can’t be an asset in a survival game that calls not only for keen eyesight and aerial acrobatics, but also a perfectly functioning beak.

Killer windows

This injury reminded me of the classic Far Side cartoon by Gary Larson, showing an audience of insects at a movie called “Return of the Killer Windshield.”  For birds, though, the horror is windows.

Experts estimate that between 365 and 988 million birds per year in the U.S. die after crashing into windows. That could be anywhere from two to 10 percent of the total bird population. According to ScienceNews,  “The biggest share of the deaths comes not from glass massacres at skyscrapers but from occasional collisions with the nation’s many small buildings, says Scott Loss of Oklahoma State University in Stillwater. ‘It’s death by a million nicks.'” So, the biggest impact is lower buildings – such as our homes – because there are so many more.

Birds hit the windows at the back of our house from time to time. In winter, when Cooper’s Hawks swing by our feeders like kids visiting the drive-through at Filiberto’s, birds flee in panic, sometimes straight into our windows. Usually they pick themselves up and fly away, but that’s not necessarily a happy ending. Often the bird dies later from internal bruising or bleeding, especially on the brain. Last week we found a male Gila Woodpecker dead on the patio, and yes, I cried.

But we can reduce the number of birds that hit our windows if we take action.  Sheri says to hang feeder 30 inches or less, or more than 30 feet, from your windows. Other more elaborate measures are described on the All About Birds website, hosted by the Cornell Lab of Ornithology. Check it out for good information on why birds fly into windows and how you can prevent collisions. A German company has even developed a glass coating that mimics spider webs, which birds can see and avoid.

It’s worth it to try.

 

Advertisements