by Joshua Morris, Urban Conservation Manager

What do a glass manufacturer in California, an app developer in New York City, and the entire membership of Seattle Audubon have in common?  

They are all part of our plan to make our city safer for birds. 

Seattle Audubon is proud to introduce Bird-safe Cities, an ambitious new initiative that aims to reduce urban hazards to birds. The work is generously funded by Jim and Birte Falconer. You can learn more about their motivation to support Bird-safe Cities in this interview with the Falconers and Seattle Audubon’s Executive Director, Claire Catania.  

Glass is one of the worst human-related causes of bird mortality, killing up to one billion birds per year in the United States (Loss et al. 2014). Over half of bird-window collisions occur at buildings four stories or lower and in relatively undeveloped places surrounded by habitat (Hager et al. 2017). More than 75% of Seattle’s land area is zoned for buildings four stories or lower  (City of Seattle GIS Program 2019) and these areas, particularly land zoned as “Single Family Residential,” tend to support high tree canopy cover in Seattle (O’Neil-Dunn 2016). Tall trees in yards and other complex vegetation near a building may increase the likelihood of bird-window collisions (Kummer et al. 2016). LThusarge portions of our city may be ecological traps for some birds—places that attract birds but that may ultimately impact their survival or reproductive success. 

We have only a limited understanding of the specific impacts of Seattle’s built environment on our resident and migratory birds. However, data from our friends at Progressive Animal Welfare Society (PAWS) suggest that collisions occur across the region and affect a wide range of species. Over the last 10 years, PAWS admitted over 1,100 birds for collision-related injuries from 84 bird species. It is important to note that these cases likely represent just a small fraction of the total number of collision victims; many are undetected and unreported. Some species show up at the hospital more often than others—just 10 species account for over half of the collision patients, and members of the Thrush family represent nearly a quarter (Table 1). Some of the species that seem to be more susceptible to window collisions have already experienced steep population declines  (North American Bird Conservation Initiative 2016) and/or are at elevated risk of extinction due to climate change (Bateman et al. 2019). If we are to keep common birds common and prevent rare birds from going extinct, we must address hazards in the built environment.

Table 1. The 10 bird species most frequently admitted to PAWS wildlife hospital for window-collision injuries from 2010-2019, including Conservation Status and Climate Vulnerability Status.

SpeciesBird Type % of PAWS Collision PatientsConservation Status*Climate Vulnerability Status+
American RobinThrush10%Low Concern Moderate
Northern Flicker Woodpecker 9%Low ConcernModerate
Varied ThrushThrush7%Moderate ConcernHigh
Dark-eyed JuncoSparrow6%Low ConcernHigh
Anna’s HummingbirdHummingbird5%Low ConcernLow
Swainson’s ThrushThrush4%Low ConcernHigh
Pine SiskinFinch4%Moderate ConcernModerate
Hermit ThrushThrush3%Low ConcernHigh
Golden-crowned Kinglet Kinglet3%Low ConcernModerate
Rock PigeonDove3%Low ConcernStable
*Conservation Status from State of North America’s Birds 2016
†Climate Vulnerability Status from Survival by Degrees: 389 Bird Species on the Brink

Our Plan

We believe that by improving and communicating our local understanding of bird-window collisions, we can inspire individuals and city governments to reduce hazards to birds. 

We have identified several strategies that will help us achieve our goal (Figure 1).

To improve our understanding of the collision issue locally, we will:

  • partner with New York City Audubon to expand d-bird, an online bird mortality database, so people across the North America can easily report bird strikes.
  • develop a collision monitoring program to provide more robust insights on the issue and help us answer questions like, “How many birds are killed in Seattle due to window collisions each year?”
  • Collect people’s stories and experiences with window collisions so we communicate the emotional impact of the issue.

To inspire individual action, we will:

  • Enable bird-lovers to bird-safe their homes.
  • Motivate architects and developers to use bird-safe building designs and materials.
  • Install collision deterrent art by local artists to raise awareness.

To influence city-wide policy, we will:

  • Build a diverse coalition of organizational partners for goal setting and strategizing.
  • Drive grassroots advocacy urging city leaders to adopt bird-safe building standards.

The success of this work depends on all of us. Our birds will need your help over the coming years as we strive to make our city more hospitable for birds. A great way to start is by joining the Seattle Conservation Activist Network (SCAN) to ensure that you receive conservation action alerts and keep connected with our Bird-safe Cities initiative.


References Cited

Bateman, Brooke L., Chad Wilsey, Lotem Taylor, Joanna Wu, Geoffrey S. LeBaron, and Gary Langham. (2019). North American Birds Require Mitigation and Adaptation to Reduce Vulnerability to Climate Change. Preprint at https://www.biorxiv.org/content/10.1101/798652v1

City of Seattle GIS Program. (2019). Land Use Zoning GIS data. Last updated January 2020.

Hager, Stephen B. et al. (2017). Continent-wide analysis of how urbanization affects bird-window collision mortality in North America. Biological Conservation. 212, 209-215.

Kummer, Justine A., Erin M. Bayne, and Craig S. Machtans. (2016). Use of citizen science to identify factors affecting bird-window collision risk at houses. The Condor. 118(3) : 624-639.

Loss, Scott R., Tom Will, Sara S. Loss, and Peter P. Marra. (2014). Bird–building collisions in the United States: Estimates of annual mortality and species vulnerability. The Condor. 116, 8-23. 10.1650/CONDOR-13-090.1.

North American Bird Conservation Initiative. (2016). The State of North America’s Birds 2016. Environment and Climate Change Canada: Ottawa, Ontario.

O’Neil-Dunne, Jarlath. (2016). 2016 Seattle Tree Canopy Assessment.