For the Birds Radio Program: Window Feeders

Original Air Date: April 11, 2013 Rerun Dates: April 2, 2021; April 14, 2015; April 29, 2014

The number of feeder birds colliding into our windows drops dramatically when we move the feeders directly onto the windows.

Duration: 3′58″


If our eyes are windows to our soul, our windows can be our eyes to soul-enriching birds, at least while we’re indoors. So it is achingly ironic that so many birds collide with windows.

Daniel Klem has spent his career as a professor at Muhlenberg College researching window collisions. He painstakingly established, step-by-step, that birds don’t see glass; that the head injuries they sustain in window collisions kill some outright and many others later; that predators capitalize on stunned birds, increasing window-collision mortality; and that the number of birds killed at windows is astonishingly high—on the order of a billion dead birds every year in the United States alone.

If his research findings are grim, he has also studied effective ways of making windows safer for birds. He works with glass and window manufacturers, trying to develop glass that is more visible to birds, and has done experiments to help us prevent collisions with the windows we already have.

One important discovery is especially important for those of us with bird feeders. Klem learned that feeder bird kills are most frequent at windows 15 to 30 feet from a feeder, and kills drop to virtually zero when feeders are closer than 3 feet from the window. This may be both because at that close distance, the birds are more likely to see the glass, and because if they do take off in a hurry and hit the glass, they’re not going fast enough to seriously injure themselves.

This is great news for those of us who feed birds. By placing our feeders right on or next to our windows, we not only get the best possible views of birds but are also protecting them. Feeding stations too large to place directly on or right next to windows should be placed at least 30 feet away, especially from windows showing a clear path to trees or houseplants, windows that reflect trees or sky, and windows with a track record of collisions.

Several kinds of feeders, including small acrylic dish feeders, suet feeders, and hummingbird tube feeders, can be placed right on window glass via suction cups. I have good luck keeping these feeders stuck to the glass by setting them on squeaky clean glass after rubbing my finger on the suction cup many times, warming it and getting some oils from my finger onto it. Suction cup feeders can support birds as heavy as Pileated Woodpeckers.

I also have two larger tray feeders, purchased from a bird-feeding store, with suction cups and a cushioned brace holding them against the glass. They stayed up surprisingly well until gray squirrels started dropping down from the roof onto them.

We’ve also screwed tray feeders into the window frame, and suspended hanging feeders from the eaves. These feeders have given me wonderfully close looks at birds, and I’ve not had a window fatality since I read Daniel Klem’s research and moved the feeders to the windows years ago.