Collisions with structures, particularly the windows of low-rise buildings, are the second largest contributor to the direct mortality of birds in North America.  Recent research by Cornell University demonstrated that Kansas City is the 6th-worst city in the U.S. for avian window strikes due to its location in a major migratory pathway plus the configuration of buildings and electric lights. Lights illuminated at night can cause migrating birds to become disoriented and come down into urban settings.  However, most collisions actually occur during daytime hours as birds are foraging, as they try to move towards vegetation that is on the other side of a transparent window, or is actually a reflection in glass. The issue of building collisions can largely be mitigated by installing bird-safe glass or by affixing after-market products that render windows visible to and avoidable by birds. Usually, it is not an entire building that requires mitigation but certain windows or portions of windows. Typically birds are colliding only with a small portion of a particularly reflective window, making mitigation an obtainable goal.  

MRBO, along with our friends at Burroughs Audubon Society of Greater Kansas City (BAS) and Johnson County Community College (JCCC) have launched a new program to reduce bird collisions with buildings in the Kansas City metropolitan area.  Working with BAS and JCCC volunteers and with Missouri and Kansas Master Naturalists, we are conducting carcass searches at buildings and determining exactly which windows are causing strikes and allowing for mitigation efforts to be focused and less costly to building owners.  Buildings can be surveyed year-round, but emphasis is on Spring migration (1 April-31 May) and Fall migration (1 September- 15 November) with the goal of surveying at least 2-3 times per week. Buildings were chosen for surveys based on 1) a history of reports by birdwatchers and other concerned citizens that carcasses had been found anecdotally over the past ~10 years and/or 2) having a window and vegetation configuration that is strongly correlated with avian collisions.

A Lincoln’s Sparrow found in Spring 2019. Photo K. Anton.

The pilot season in spring 2019 identified several buildings where bird strikes were frequent, as well as several buildings that require additional surveys. BirdSafeKC coordinators and volunteers have initiated outreach to building owners and managers to encourage mitigation efforts and, where accepted, help acquire and place appropriate window treatments. As the survey and outreach portions of BirdSafeKC expand, we are also developing a larger public education strategy to raise awareness among Kansas City residents about this issue.  The BirdSafeKC program is modeled upon successful efforts in Chicago, New York, and San Francisco to engage local residents and to provide good public relations for building managers that work to reduce bird strikes. 

We consider BirdSafeKC a long-term program, as the collision issue is large in scope and requires continual efforts. As an example of the size of the issue, the JCCC campus in the suburbs of KC documented over 500 bird kills in a single year. Mitigation at this site is drastically reducing collisions and serves as an example for sites identified by BirdSafeKC.

See the results of our first season here.

Carcass surveys will continue at sites post-mitigation to demonstrate improvement, as well as at new buildings identified as potentially strike-prone. Outreach to building owners and the public will be ongoing endeavors. To learn more or get involved, please email

A Ruby-throated Hummingbird flies near a window that has been treated with adhesive dots that alert birds to the window’s presence.