Birds and Windows

birds-and-windowsIt has been estimated up to 1 billion birds are killed in North America each year as a result of bird window collisions! This is one of the largest threats facing urban bird populations. Residential homes are estimated to represent 90% of building-related mortality, directly related to their large number compared to other building classes. However, more work is needed; only four studies in the past have focused on bird window collision mortality at houses.

The University of Alberta Birds and Windows Project was designed to use citizen science and active participation to continue to identify the factors that affect collision risk at residential homes.

Window glass is an invisible barrier to birds, and collisions occur as birds attempt to fly through what appear to be reflections of open space and vegetation. Generally, this occurs as a result of panic flights where birds panic due to pursuit by raptors, the presence of cats or larger birds arriving at feeders, loud noises, and being chased by other birds.

Environment factors, such as nearby trees and shrubs, and the presence of bird attractants, such as bird feeders, bird houses and bird baths, have been shown to increase the abundance of bird window collisions.

Bird_Imprint_on_Window_0075To better understand what can be done to reduce bird window collisions, the University of Alberta has developed this project to actively involve you in data collection. They are looking for people to search for evidence of bird window collisions on a regular basis. Ideally you will search your residence daily for a period of at least one month.

The researchers prefer daily searches as previous studies have shown this reduces the chance of evidence being lost due to searcher error or evidence being removed by scavengers. If window collision evidence is observed at a time other than during a perimeter search try to complete a full search at this time to maintain consistency and account for the possibility of multiple collisions.

Evidence of bird window strikes include dead or injured birds found beneath a window or blood smears, body smudges or feathers found on the window glass. To help in understanding what happened to the bird when it collided, please take a photo of the collision evidence to be uploaded to the survey. Photos will help provide accurate species identification. If a dead bird and a body smudge on the glass are found for the same collision, take a picture of the bird as it will be used to identify the species.

After creating an online account, enter data about bird-window collisions by answering a series of questions and uploading photographic evidence.

For complete details visit  and if you have any questions.