It was a late Monday night and the buying club delivery had just arrived. I stood by the white van chatting with the owner's friend about The Omnivore's Dilemma and how wonderful it to find humanely and sustainably produced animal products such as the grassfed beef, pastured pork and eggs, raw milk delivered to our club. Suddenly, my companion looked up at the clear sky - the stars shimmering against the black night - and inhaled. "Wow, you don't have much light pollution around here," he admired. I had never heard that term before but agreed nonetheless taking in the distant stars and planets. After signing for our order, I waved goodbye and went inside, leaving my porch light on.
Home safety experts sometimes advise leaving outdoor lights on at night to deter unsavory sorts from skulking about. I have diligently left my light on for years for that very purpose. In a nod to living lighter, I long ago replaced the incandescent bulb that burnt out monthly with a long lasting CFL bulb. I've since learned, though, that there is no evidence that artificial lighting deters criminal activity. Moreover, such lighting can create deeper shadows in which criminals might hide. If safety concerns remain, motion detectors and other strategies are more efficient and effective.
I never gave another thought to my acquaintance's comment about light pollution until I came across an article about it last week. Apparently, lights left on at night, like porch lights and office lights, greatly impact the population of migratory birds which use the stars to navigate. These birds often become disoriented by the plethora of lights in cities and densely populated suburbs, like mine. Indeed, as many as 900 million birds crash into buildings annually because they are confused by the bright lights. Moreover, night lights negatively affect turtle hatchlings, salamanders, and juvenile seabirds to name a few.
The more I learn about leaving my light on, the more reasons I encounter to turn it off. From now on, I'll give my porch light, my electricity bill, and the birds a rest and leave the job of lighting the night to the stars and moon.