For the birds: 5 tips to make feeders safer

    Our Bird Nerd delves into research about bird collisions with windows

    By Julienne Morissette, ’14 PhD, for Thought Box on November 27, 2015

    If you’ve ever walked into a glass patio door, you know it can be painful (not to mention embarrassing).

    For birds, it can be fatal. Bird collisions with windows account for about 25 million bird deaths a year in Canada, and 90 per cent of them involve homes. Given an unprecedented growth in urbanized space, these collisions are seen as a potential threat to wild bird populations in North America.

    Justine Kummer, ’11 BSc, is researching ways to reduce collisions. Her Birds and Windows Project at UAlberta is using the public — or “citizen scientists” — to help collect data. Part of her research has been published in the fall issue of the journal Avian Conservation and Ecology.

    Previous research has pointed to bird feeders as a possible culprit in increasing bird-window collisions, so one of Kummer’s research questions was, “Does the distance of feeders from windows affect the number of collisions?”

    Working with volunteer homeowners, Kummer set up 55 study windows and observed each one in three states: without a feeder, with a feeder one metre from the window and with a feeder five metres away. Each homeowner was asked to search for evidence of collisions such as window marks or dead birds and to provide a daily report. Results were obtained over all four seasons.

    The study found that collisions were almost twice as common at homes with feeders than without; that the distance of feeders from homes had less impact on the number of collisions than other factors, such as season (collisions were highest during spring and fall migration, when bird traffic is greatest); and that close to half the study windows had no collisions, which suggests that other factors, such as abundant vegetation, may be factors.

    Kummer stresses that despite the risks, “feeding birds has the important benefit of providing an important link between the general public and nature, which ultimately raises awareness of biodiversity and conservation.”

    Avoiding collisions

    Kummer has advice to help reduce bird collisions with windows, pulled together from her work and that of other scientists around the world.

    • Place feeders within one meter of windows — birds will still use the feeder but most can’t build enough momentum to sustain serious injury if they hit the glass as they leave the feeder.
    • Placing feeders more than 10 meters from a window will also reduce risk. At this distance, birds are more likely to recognize the reflected image as part of a house.
    • Move houseplants and flowers away from windows, where they cannot be seen from outside. Birds will be less likely to mistake them for shelter or food.
    • Apply window decals or hang strings of objects to break up reflections, make transparent windows more visible and create a visual barrier.
    • Use ultraviolet window decals or windows with a UV pattern built in. Birds have colour receptors in the eye that allow them to see the ultraviolet portion of the color spectrum. Research has shown that UV patterns are highly visible to birds, though almost imperceptible to humans (flap.org) and can reduce collisions dramatically.

    Kummer’s work on her master’s research is coming to an end — but not her love of conservation work. “The science is interesting, but the most rewarding part is working with people and helping them understand that conserving birds for future generations is important and how my research can help.”


    Julienne Morissette, ’14 PhD, has worked in research and conservation for most of her career and has focused largely on studying how birds might respond to natural or anthropogenic (caused by humans) changes in their environment. Her favourite bird encounter was watching hawks circle by the thousands, preparing for flight over the Gulf of Mexico. Morissette works for Ducks Unlimited Canada.

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