UBC Undergraduate Research

Invisible to visible : A field study investigating dirty windows and bird-friendly artwork as mitigation strategies against bird-window collisions Leung, Kelsey


Estimates suggest that 16 to 43 million bird deaths occur annually due to collisions with buildings in Canada. Buildings on the University of British Columbia Vancouver campus may contribute up to 10,000 bird deaths each year. The reflective and transparent properties of glass, combined with birds having poor spatial acuity in the direction of motion, make it challenging for birds to perceive glass as a solid barrier, resulting in bird-window collisions. This study investigates the effect of two mitigation strategies employed by the UBC Botanical Garden: reducing window washing frequency, which allows dirt to accumulate on windows and the installation of bird-friendly artwork. A comparison of collision frequency over an 8-week monitoring period in late winter and early spring of 2021 and 2022 is used to investigate the effectiveness of these strategies. A 97% decrease in collision evidence was reported from 2021 to 2022, suggesting that dirty windows and bird-friendly artwork are effective at reducing birdwindow collisions. We recommend that both strategies should be implemented at other buildings on the UBC campus and suggested to businesses and homeowners to reduce the negative impact windows have on bird populations. Further studies should be conducted on the effect of dirty windows, as limited research directly investigates this strategy. Additionally, a comparison between the effectiveness of dirty windows, bird-friendly artwork, and other mitigation strategies (such as decals or ultraviolet film application) should be conducted to determine which offers the highest level of protection against bird-window collisions. Future research should also investigate social aspects of bird-window collisions, including public perception and awareness, in order to improve mitigation strategies and better understand barriers to their implementation. Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report.”

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