Turning Off Home Lights: NO Scientific Justification
Jim Cubie Ornithology Center at Muhlenberg College
I followed this quote, “make a big difference” all the way back to its source. When asked the question, “How could this be?” I was referred to the Van Doren paper. It is the only study showing that light management in a building can reduce window collision deaths. His text says that it applies to low rise buildings with large window spaces and with lights which are often on all night. It does not apply to homes, with a few lights on for few hours. I confirmed this in a phone call with him.
If homeowners think that they can help birds by just turning off a light, why would they install a permanent system?
No outreach document should deliver the message that turning out home lights makes any difference.
Please consider offering this message: “while we are working hard to prevent bird collisions downtown, the best way for you to help is by installing bird window collision prevention in your home. As many birds die hitting home windows as die hitting low-rise buildings.”
For information about these scientifically tested systems see the “Consumer Guide to Bird Window Strike Prevention.” It includes a description of all the scientifically validated systems, compares prices, compares the effect on vision out the window of options and includes DIY directions for all.https://ornithologycenter.com/sdm_downloads/consumerguide/
WINDOW ALERT AND WINDOW GEMS DECALS DO NOT WORK. See https://birdfriendlyyards.net/sdm_downloads/windowalertbadforbirds/
Wrong Information Causes Real Harm.
It may be said, “but it does no harm” if we tell people to turn off lights at their homes. That is wrong. It does cause harm. If you advise a friend that he use natural treatment for cancer, but he needs chemotherapy, your advice certainly harms him. He dies. It is the same if we advise people that they can save birds by turning out lights in homes. Birds die. What birds need is scientifically validated window collsions systems that actually save birds. The result is thousands of birds of dead birds. These birds would have been saved if we had convinced homeowners to install permanent window collision prevention systems. If the Lights Out campaign convinced 100 homes to install bird window collision prevention, it would save 2,000 birds over the next 10 years – twice that if they feed birds.
Home Lights Out – zero saved;
Permanent Installed Systems – 2,000 birds saved.
No ALAN Effect. It equally defies common sense that turning off a home light – even two thousand home lights – can have any effect on the over all light level above a city. In Chicago, there are 250,000 street lights and about as many again in the surrounding cities. The 250,000 street lights in Chicago emit 2,250,000,000 lumens. Note that is a “B”- billion. Add to that all the other lights in tens thousands of buildings. If a campaign convinces 1,000 bird lovers to turn off two (2) security lights, and they in turn convince a 1,000 of their neighbors to do the same, the lumen reduction is 0.0267% of the street lights. How many birds will be saved?
Thanks to the Cornell Lab for helping to resolve this matter.