Each year, billions of birds pass through the United States on their way to seasonal destinations. And each year, these birds are among the 600,000 birds that die after colliding with buildings. Cities like St. Louis pose a disproportionate risk to birds, as the geography, developmental spread and glow of night time lights converge to create significant obstacles to these long-distance travelers.
80% of migrating birds migrate at night, using the moon and stars to navigate. Light pollution from cities disorients birds, drawing them into the glow and causing them to waste valuable energy, often trapping them in a circle until dawn. Exhaustion makes them more vulnerable to other threats, like predators or flying into glass buildings, which are also abundant in cities.
St. Louis ranks among the top 5 of the worst cities for migrating birds. In response, Lights Out Heartland, a local initiative in collaboration with the National Audubon Society and the Missouri Chapter of the International Dark-Sky Association, launched to spread the word to encourage residents and businesses alike to limit light pollution, especially during the peak migration months, starting in late April through May for spring migration and the months of September and October for fall migration.
Washington University in St. Louis has incorporated protecting biodiversity into its approach for operational sustainability. Like many sustainability solutions, our approach to prioritize sustainability in our buildings and landscapes has many benefits. Interior lights on motion sensors or schedules reduces the energy use of a building, but also eliminates unnecessary indoor light from seeping into the night time sky. Dark-sky certified lighting that is energy efficient, angled downward, and capped to prevent light from beaming upward will also protect birds and other nocturnal animals. Native landscapes hold stormwater onsite and require less irrigation, while also providing food and shelter for migrating and full-time native birds alike.
This spring, WashU has signed on to the Lights Out Heartland initiative, both as an outreach partner as well as a building partner, with a specific plan to turn off unnecessary lights while educating our campus community about this important issue. While the problem of light pollution is at a global scale, it is one that we can address at local, institutional, and individual levels.
To put together an operational plan, Cassie Hage, Assistant Director of the Office of Sustainability, consulted a broad range of partners and experts, including Brett Seymoure, a Postdoctoral Fellow with the Living Earth Collaborative, Anne Tieber, Curator of Birds at the Saint Louis Zoo, and Jonathan Lasos, Director of the Living Earth Collaborative. Colleagues Beth Biro and Solny Adalsteinsson, staff scientists at Tyson Research Center, shared strategies about how WashU’s environmental field station was participating in the initiative and collaborated on efforts to engage the community in monitoring bird activities on campus.
Along with direction from WashU’s police department and operational experts from the Facilities Planning & Management department, the team put together a prioritized list of the most problematic lights, and determined the duration of time off that would have the optimal impact on bird migration. A key tool in the assessment process was aerial drone footage that provided a “birds eye view” of campus at night. From this vantage, it was easy to see which lights were shining up, a tell-tale sign of light pollution.
In reflecting on the process, Cassie Hage shared, “the good news here is that we have confirmed that, for the most part, WashU’s campus has exemplary night time lighting, both from wildlife and safety perspectives. By implementing the suggested changes and continuing to evaluate light pollution, we can provide regional leadership and demonstrate how campuses can operate 24/7 beautifully and safely while balancing the needs of the natural world.”
According to the International Dark-sky Association, light pollution is the inappropriate or excessive use of artificial light. Light Pollution has serious health consequences for humans, wildlife, and our climate.
In less than a single human life time, 50 years, 2.9 billion breeding adult birds have been lost from the United States and Canada. That is more than a quarter of birds gone since just 1970, according to findings reported in Science by researchers at 7 institutions. The main threats to birds include:
- Loss of habitat & habitat degradation
- Cats and other invasive species
- Collisions with glass and industrial infrastructure like communications towers and wind turbines
- Exposure to pesticides and other toxics
- Climate change exacerbates these threats and creates new challenges
WashU takes a holistic approach to sustainability, seeking decision-making and solutions that have many benefits. For example, most new landscapes and renovated landscapes utilize primarily native plants suited to the microclimate and soil where they are situated. In addition to benefits that include reducing the need of irrigation and chemical pesticides and improving storm water management, this treatment of landscape creates habitat for birds and other wildlife.
Similarly, WashU seeks a minimum of LEED silver certification on all new building construction, with most recent projects earning Platinum or Gold. LEED certification encourages bird-friendly features, like window treatments or architectural features that reduce the likelihood of bird collisions. It also encourages lighting fixtures that reduce light pollution for exterior lights.
In response to concerns from WashU employees and students about bird strikes and bird health, WashU has been studying problematic buildings and other areas where we can improve. The Sustainability Exchange, an undergraduate capstone course, has a group that has been studying this issue for 2 years, collecting data on bird strikes across campus, identifying buildings that are most susceptible to bird collisions, and putting together a set of recommendations for the facilities department on how to address the issues. The birding club has also compiled data on bird collisions for the Danforth campus. In addition, a group of bird-enthusiasts at the School of Medicine is currently working on gathering similar information for that campus.
Anyone can contribute to a better understanding of bird strikes on campus by installing the iNaturalist app on their phone and joining the Bird Collision Mitigation Project at Washington University. If you discover a bird that is dead or stunned after a collision with glass, please log it here!
Especially during late April and throughout May, and the month of September, close blinds in the evening and turn off building lights when not in use. If you observe lights in your office or building that remain on all night, contact Facilities or your building or zone manager to bring it to their attend and determine if the lights could be turned off or placed on a schedule. Not only will this prevent the glow from buildings causing light pollution, but it will also save energy and associated carbon emissions.
Many people love inviting birds into outdoor spaces near their homes where they can watch and listen to these amazing creatures. However, without some basic precautions, it is possible that these encounters can be life-threatening for the birds. The American Bird Conservancy suggests starting here:
- Make windows safer, day and night.
- Keep cats indoors (or contained)
- Reduce lawns by planting native species
- Avoid pesticides both in what you directly use in your home and garden and also through your food choices.
- Drink bird-friendly coffee
- Avoid single use plastics
- Contribute to monitoring bird populations through citizen science efforts by using apps like eBird or iNaturalist to report the birds you see
Also, see below to minimize light pollution during migration times and year round. Using light more thoughtfully will reduce light pollution for the region and can also save you money through energy conservation!
The simplest action is to simply turn off exterior lights that are not needed. While unnecessary lights should be turned off and removed permanently, it is especially important that they are turned off during seasonal bird migration (May and September). When not possible to turn off or remove lights, follow these guidelines:
- All lights should have a clear purpose – only light the area that needs it.
- Use energy efficient bulbs that are no brighter than necessary.
- Use fully shielded light fixtures (pointed downward).
- If lights are only needed for short periods, put them on a motion activated timer.
- Select bulbs with warm color (amber or yellow) temperatures – less than 3000 K, and preferably close to 20000 K – with negligible blue light.
- Q: Does having a well-lit house/street reduce security risks? A: Not necessarily. Read more…
- Q: How does light pollution impact human health? A: Research suggests that artificial light at night can negatively affect human health, increasing risks for obesity, depression, sleep disorders, diabetes, breast cancer and more. Read more…
- Q: How can rethinking lighting save energy? A: Eliminating unnecessary lighting and reducing lighting time conserves energy, which also saves both carbon emissions and money. Learn more…
- Q: Does “lights out” mean all lights out? A: No. The Lights Out initiative is simply encouraging building owners and residents to assess their current lighting and remove, turn off, or dim unnecessary lighting. Any remaining lighting should be accessed to determine if the light is the right brightness, right color, and right angle. Making these changes will eliminate light pollution, increase safety, improve human health, and save the building owner money! See the difference.
Lights Out Initiatives in the News
Lights out: Maps track massive US nightly bird migration
New York City Passes Landmark Lights-Out Laws
Questions? Contact Cassandra Hage, email@example.com.