Mornings are typically a time for me to quaff hot coffee while staring out the sliding glass doors to my back deck, where a seed feeder attracts house finches, Carolina wrens, Carolina chickadees, tufted-titmice, American goldfinches and migratory drop-ins like rose-breasted grosbeaks. But on this Tuesday, something went awry. I was in the kitchen when a crack to the glass sent adrenaline shooting through my core. I was at the slider within seconds and saw her there… on her back, beak moving repeatedly but emitting no sound, legs clawing at the air.
A female house finch had flown full force into our window. A patch of disturbed feathers on her crown told me she had either struck her paper-thin skull quite hard, or broken her neck. I scooped her up and cradled the length of her body in my palm. If I brought her inside, I thought, perhaps she’ll rest past the shock.
Not so. Her legs and tail quivered in a death rattle. Her emory-black eyes glazed. She died in my hands. I held her till she was no longer warm, then sadly set in her in a paper bag to walk down to the Haw River later and place her where a fox, raccoon or other passing scavenger might benefit from her.
On the back deck, her friends continued to crack seeds and mine for cashews around the feeder. Someone would be missing their mate tonight, or their mother or their buddy.
How to stop bird strikes? I wondered. It was the second fatality my home had incurred in six months; each one left me racked with guilt for attracting the birds to my yard. In a third (non-fatal) strike, a downy-haired woodpecker was left with what I am sure was a concussion. After racing outside post-reverberating smack! I’d found him hopping, dazed on the ground. Afraid of me, he flew in erratic circles 20 feet upward then clung to the craggy bark of a pine tree. For three hours, he listed precariously off the tree, tail feathers bracing more than his talons seemed to be.
In nearly all cases, birds simply can’t see glass or don’t recognize it as a fixed barrier. In some cases, they mistake their reflection for an invading bird stealing in to their territory. They fly full force at it, hoping to bluff the intruder away with bravado, or fight it outright.Unfortunately, bird casualties due to collisions with windows take a huge toll annually.
To prevent either sort of strike, it’s imperative to break up the reflective surface. A quick internet search pulled up some promising results for preventing bird strikes on your home’s windows:
- Place removable stickers or decals on the exterior face of the window to disrupt reflections. Try commercially available decals in the shape of predatory birds such as falcons and owls, or urban predators such as cats. These visual cues may deter birds from getting too close.
- If you don’t want to spend money, and have latex paint on hand, try painting designs on the exterior face to break up reflections. (Latex paint is easily removed from most glass surfaces, but test a small surface portion before embarking on larger murals.)
- Use window coverings on the inside of the window, which can cut down on the exterior reflectivity.
- If you have a seed, nut or fruit feeder close to your home that attracts birds in and leads to strikes, move the feeder farther from your home (buy some binoculars).
Although nearly two decades old, this paper from the Journal of Field Ornithology provides an experimental framework for testing various window treatments, including the commercially-available silhouette decals and white window covering treatments. The author, Daniel Klem, found that the most effective deterrents were not the owl and falcon decals, as you may intuit, but that:
“Only four preventative methods resulted in statistically significant avoidance for all subjects. All Juncos avoided windows that were completely covered and rendered translucent by a white cloth drape, and three patterns consisting of 2.5 cm wide white cloth strips that uniformly covered the entire window. The effective patterns were: (1) a rectangular mesh forming 8 cm wide by 10 cm high openings, (2) vertical strips separated by 10 cm, and (3) horizontal strips separated by 5 cm. ” (Klem. 1990. Journal of Field Ornithology. 61(l):120-128)
Sadly, Klem also found that about 50 percent of bird strikes at his two urban test sites were fatal, even when birds of variable sizes were factored in (they tested two weight classes: less than 39 grams for hummingbird to sparrow-sized birds; and more than 39 grams for cardinal to bobwhite-sized birds).
Have you successfully prevented bird strikes? Know someone who has? Know of more recent research than what you see here? Drop me a line, I’d love to know how to keep more birds alive and in the trees and sky.