The beautiful glass buildings, low and high-rise, look like landscape marvels with the reflection of trees and clear blue skies. Those neat looking buildings may look good to people, but they are bird killers. Utah State University professor Kimberley Sullivan estimates a billion birds are killed in the United States due to collisions with glass.
Glass buildings and windows in homes are the second leading cause of death to birds. A 2017 bird study from USU estimates 10 percent of the world’s bird population is killed running into glass windows.
Dr. Sullivan has conducted research on the behavior, physiology and ecology of a number of bird species.
“Birds don’t see glass,” she said. “Neither do we as humans. We know it is there, but we don’t see it.”
She said the bird collisions on campus made for some interesting studies for her biology students.
“Some of our students go around and collect carcasses of birds,” the professor said. “Sometimes they collect parts of birds because cats will eat the carcasses. We also look for marks on windows that indicate bird strikes.”
Sullivan said some of the buildings on campus get hit more than others. For instance, the southwest part of the Fine Arts Visual building, and the walk-way between the Science Engineering Research building and the Engineering building. The west facing windows on Old Main and the University Inn also have a fair share of bird strikes.
Over 60 cedar waxwings were killed by colliding with the University Inn windows over the span of two days in 2015.
She said the problem is magnified when berry trees and bushes are planted close to windows. High rise glass buildings only account for eight percent of bird deaths. The rest of the collisions come from homes and low rise buildings.
In her research, Sullivan has found ways to reduce window collisions from our feathered friends. Using window screens to cover windows is a start. Screens reduce reflections and cushion the impact of the window.
Sullivan also suggests breaking up large spaces with ceramic dots, or using an ultraviolet pen to draw lines that are invisible to the human eye, but not to birds.
Another option is window film and patterns similar to bus wraps. People can see out, but people (and birds) on the outside can only see the outside image.
She said hawk silhouettes or plastic owls don’t work because they don’t move and birds become accustomed to them
Sullivan suggests it may be time to replace windows with more bird friendly glass, like UV treated windows. Treated windows are available for new construction. Another option is to provide overhangs, so the windows are in the shade.
The professor also advised placing junipers, dogwoods, crabappple trees and any other tree that produces berries away from windows.