Every Day Needs a (Dark) Night

By Adam Kreuzer

We sometimes forget that every day has a night! Unfortunately, because of the recent explosion of light pollution, our nights are now bright. Until only about 50 to 60 years ago, we had dark nights. Our grandparents and their parents walked summer nights under thousands of bright stars. Now, on the best of nights, we can see with our naked eyes not more than 40 stars. While we have adjusted somewhat to this very recent dramatic change in our environment, our birds and other wildlife friends have not.

For birds, the new widespread use of bright white LED lights at night is especially troublesome during migration. Twice a year, during spring and fall, millions of birds migrate through our area. Unfortunately, according to Cornell Lab of Ornithology, the Chicago area is the #1 most hazardous location in the U.S. for migrating birds. In addition to how buildings are built, artificial light at night is a significant cause of bird fatalities. Every year, an estimated 600 million birds die from building collisions.

The great majority of birds migrate at night. During the day, they eat to fuel their trip. At night, fueled to fly all night, some birds become distracted by bright white lights. They descend from the sky and strike lighted windows. Some fly in circles, tire, and fall on the sidewalks. In Chicago, volunteers with the Chicago Bird Collision Monitors wake early every morning to rescue injured birds. Survivors are taken to the Willowbrook Wildlife Center in Glen Ellyn. A recent 20-year study of bird fatalities at McCormick Place conducted through the Field Museum concluded that by turning off just half of the lighted windows during migration, fatal bird collisions dropped by 60%.

Bright white lights at night affect most nocturnal animals, including nocturnal pollinators. Moths, which at night pollinate flowering and fruiting plants, circle bright white lights until they are eaten or tire and die. Fireflies, which rely on their bioluminescence to find mates, are less plentiful now.  Recent research has shown that bright white LED lights, when shining into our bedroom windows, can also have an impact on human health by affecting our circadian rhythm. We sleep less and eat more. As a result, we suffer physically and mentally.

Every day needs a dark night! Fortunately, there are four easy things we can do at home to help our planet at night. Who knows, if we do these things, maybe we can see a few more stars…and fireflies!

ACTIONS YOU CAN TAKE

Flip the switch. Consider turning off outdoor lights before you go to bed. If security is a concern, turn off all but the truly necessary light(s). If available, use a motion sensor. You will save $$ and will use less fossil fuel.

Shield, shield, shield. Consider installing fully shielded outdoor fixtures that keep your light on your property instead of on your neighbor’s house or into our night sky. The International Dark Sky Association website www.darksky.org will direct you to hundreds of locally available fixtures.

Please avoid using “bright white” or “daylight” bulbs. Instead, use a more amber color, not more than 2700Kelvin. “Soft white” bulbs are 2700Kelvin.

Not so bright! LED lights are much more intense than the bulbs we once used. With your “soft white” bulb, consider using fewer watts (40, not more than 60) or lumens (450 or less). An Earth-friendly bulb, if on, is shielded fully, is less white, and is less bright.

- Adam Keuzer is an International Dark Sky Association Delegate. He provided the photos for this article.