Spring bird migration is underway, and officials in Louisville, Kentucky, are asking residents to do something surprisingly simple to help: turn off unnecessary lights at night.

As millions of migratory birds travel across the United States this spring, Louisville is ramping up efforts to reduce light pollution through a partnership with the Louisville Audubon Society and its Lights Out Louisville initiative.

City leaders say artificial light at night, often called ALAN, can confuse and disorient birds during migration, increasing the risk of deadly collisions each year with buildings and windows. According to the initiative, as many as 5 billion birds die each year in the U.S. from window strikes, with light pollution playing a major role.

"Louisville is committed to being a city that values both sustainability and environmental stewardship," said Mayor Craig Greenberg. "Participating in this important initiative will help reduce energy use and greenhouse gas emissions, lower costs, protect our environment, and support the health of our residents."

The city is now working to reduce unnecessary lighting at parks, libraries, and government buildings during peak migration seasons, especially in April, May, September, and October.

For many people, bright city lights are simply part of modern life. But for migratory birds traveling overnight using moonlight and natural navigation cues, those lights can become dangerous traps.

Birds can become disoriented by illuminated buildings, sometimes circling them repeatedly or crashing into windows. This issue is especially significant in areas like Jefferson County, where millions of birds pass overhead during migratory season.

Reducing excess lighting also benefits people. Research has linked excessive nighttime artificial light to sleep disruption and other health concerns, meaning efforts to dim unnecessary lighting can improve quality of life while also saving energy.

Programs like this also demonstrate how relatively small community actions can add up quickly. Turning off lights that are not needed overnight reduces electricity demand, lowers energy bills, and cuts pollution tied to power generation — all while helping wildlife safely navigate migration routes.

It is the kind of solution that benefits both ecosystems and neighborhoods at once.

Louisville Parks and Recreation said it is incorporating bird-friendly lighting standards into new projects while identifying opportunities to retrofit existing facilities. Staff are also being trained to reduce excess lighting during migration periods and implement strategies that help prevent bird strikes.

Residents and businesses are encouraged to participate as well. The city recommends turning off non-essential indoor and outdoor lights between 11 p.m. and 6 a.m. during migration months. 

Officials also encourage people to close blinds and curtains at night to reduce light spilling outdoors.

Other recommendations include switching to warmer-colored LED bulbs between 2700 Kelvin, using motion sensors for outdoor lighting, and pointing outdoor lights downward instead of outward or upward.

The Lights Out Louisville campaign also offers a free pledge that residents and businesses can sign to commit to reducing unnecessary nighttime lighting.

"This partnership is a natural fit for Louisville Parks and Recreation and the values we bring to our work every day," said Michelle King, executive director of Louisville Parks and Recreation.

And as Lights Out Louisville program chair Mary Beth Nevulis put it: "It's not about doing it all — it's about doing whatever you can. Every action adds up, and everything makes a difference for conservation, and for birds."

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