Demand for Darkness by Josh Palumbo, Forest Management Coordinator. I had the privilege to travel to Colorado for the first time in my early teenage years. An individual’s initial visit to the wild west changes your thinking on so many topics. A big mountain on the east coast is not quite as impressive once you have walked among the “fourteeners.” Who would have guessed green is not a universal landscape color once you cross the mighty Mississippi? I was amazed to find shooting stars are incredibly common and a part of most nights sky if you can see it clearly. This edition of the Nine Minute Naturalist will delve into the idea of light pollution and how we at Wintergreen can make stargazing a focal point of our community.
Darkness is a vital part of human and ecosystem health. For the vast majority of human history, the natural cycle of light and darkness ran through our lives. The circadian rhythm, our 24-hour cycle that regulates our physiological and behavioral processes, is based on a light and dark phase to our cycle. Disruption of that cycle can lead to insomnia, hypertension, depression, heart disease and many more problems. Our natural melatonin production can be halted by just 15 minutes of bright light in the evening.
Wildlife is also dependent on darkness. The mass bird migrations that happen in spring and fall are done largely at night. Many of our beloved migratory birds that are on their way to Wintergreen right now travel at night. Nighttime travel offers the guidance help of the stars and moon, helps them avoid predators such as hawks, offers calmer air and cooler temperatures. Light pollution becomes a big problem when it inhibits their ability to use the stars and moon, especially when traveling under cloud cover. Light will attract them from almost 5 miles away. Mass mortality events have been recorded when foggy conditions combine with strong light pollution and birds fly into buildings due to the attraction of light. Many of our most beloved warblers, sparrows, vireos, and waterfowl use darkness as their primary travel times. Darkness also plays a key role in the predator/prey relationship happening every night at Wintergreen. Our wildlife is dependent on either the ability to hide better in complete darkness or the ability to stalk better in the dark. Our introduction of light changes that cycle.
According to International DarkSky Federation, light pollution has four components: Glare which is excessive brightness that causes discomfort, Skyglow which is brightening night sky over inhabited areas, Light Trespass which is light falling where it is not intended or needed, Clutter which is bright, confusing, and excessive groupings of light. It is estimated that 99% of the population in the United States live under skies damaged by light pollution. No matter what we do at Wintergreen our night sky is compromised but we can try to improve our east coast sky visibility.
DarkSky International lays out five principles for outdoor lighting that can go a long way to improve our presence in our environment and enhance our stargazing. The first principle is that outdoor lighting should be useful. Ask yourself is this light needed and does it have a clear purpose? The second principle is that light is targeted. This means that you focus just on what needs to be illuminated and do not allow it to spill outside that area. The third is that the light is the lowest level required and no brighter than necessary. The fourth principle is that outdoor light is controlled. This involves controls such as dimmers or motion lights that turn off when not needed. The last principle is that lights are warm-colored. Use lights that have a shorter wavelength (blue-violet).
Virginia’s Dark Sky Week is coming up on April 21-28th. This designation was brought about to bring awareness to the awesome resource a brilliant night sky is to all sky gazers. Let us as a community attempt to do our small part to make sure migratory birds can arrive safely and that Wintergreen can be considered a place where the night’s sky is truly valued.
