Analysis of Bird-Window Collisions on the Illinois Wesleyan University Campus
Major
Environmental Studies
Submission Type
Poster
Area of Study or Work
Biology, Environmental Studies
Faculty Advisor
Given Harper
Location
CNS Atrium
Start Date
4-13-2024 8:30 AM
End Date
4-13-2024 9:45 AM
Abstract
North American bird populations have declined by about 30% since 1970 (Rosenberg et al. 2019). One major mortality factor is bird/window collisions, which is estimated at 599 million collisions a year in the United States (Loss et al. 2014). Most of the birds killed are songbirds, which migrate at night and then feed in the morning to acquire energy for the next stage of their migration. Birds are often killed when they fly into windows that reflect the sky and vegetation. Our study aimed to document the frequency of bird/window kills on the Illinois Wesleyan University campus during the spring and fall migration and determine possible contributing factors. Searches for bird carcasses were conducted daily beneath eight buildings (Ames Library, CLA, CNS, Gulick, Holmes, Ames Art Building, Presser Hall, and State Farm Hall) from 5 April to 26 May 2024, and from 28 August to 16 October 2024. We found 16 birds in the spring consisting of 11 different species: these included one woodpecker, one kinglet, two creepers, two thrushes, five warblers, and three grosbeaks. In the fall, 10 birds were found consisting of 8 different species, which included one vireo, three thrushes, and six warblers. Most bird/window collisions during both seasons occurred at State Farm Hall (n = 12) and Ames Library (n = 7). There was no significant relationship between the area of glass on the building face and the number of bird carcasses found (F1,5= 2.896, p= 0.15, R2= 0.367). Additional statistical analyses are being conducted on the impacts of vegetation proximity to windows. Bird-friendly windows (i.e., fritted glass that birds can see) should be considered for future campus construction due to their ability to greatly reduce bird/window collisions (Sheppard, 2019).
Analysis of Bird-Window Collisions on the Illinois Wesleyan University Campus
CNS Atrium
North American bird populations have declined by about 30% since 1970 (Rosenberg et al. 2019). One major mortality factor is bird/window collisions, which is estimated at 599 million collisions a year in the United States (Loss et al. 2014). Most of the birds killed are songbirds, which migrate at night and then feed in the morning to acquire energy for the next stage of their migration. Birds are often killed when they fly into windows that reflect the sky and vegetation. Our study aimed to document the frequency of bird/window kills on the Illinois Wesleyan University campus during the spring and fall migration and determine possible contributing factors. Searches for bird carcasses were conducted daily beneath eight buildings (Ames Library, CLA, CNS, Gulick, Holmes, Ames Art Building, Presser Hall, and State Farm Hall) from 5 April to 26 May 2024, and from 28 August to 16 October 2024. We found 16 birds in the spring consisting of 11 different species: these included one woodpecker, one kinglet, two creepers, two thrushes, five warblers, and three grosbeaks. In the fall, 10 birds were found consisting of 8 different species, which included one vireo, three thrushes, and six warblers. Most bird/window collisions during both seasons occurred at State Farm Hall (n = 12) and Ames Library (n = 7). There was no significant relationship between the area of glass on the building face and the number of bird carcasses found (F1,5= 2.896, p= 0.15, R2= 0.367). Additional statistical analyses are being conducted on the impacts of vegetation proximity to windows. Bird-friendly windows (i.e., fritted glass that birds can see) should be considered for future campus construction due to their ability to greatly reduce bird/window collisions (Sheppard, 2019).