Did you know the wrong kind of outdoor lighting can negatively affect your sleep and therefore your immune system, can harm wildlife and can reduce biodiversity by making habitats virtually un-usable for wildlife?
Here is a summary of facts and best practices:
- Avoid white, blue and LED lights – because blue and white lighting keeps everyone (including your body) awake. White light and that in LED’s contain blue light components, and although your eye has three types of receptors for blue light, only 6% of only one of these types of receptors contributes to a coloured image-so basically very little of the total receptivity is to blue light. This is because there is very little in nature that is blue that affects our survival. In fact you mainly see it in the sky during the day and at dusk. Therefore our bodies and those of animals believe it is day or evening when white and blue LED’s are on. When white and blue lights are around at night in sufficient quantity, your body may not reach deeper stages of sleep including REM sleep. During the deeper stages of sleep our bodies repair themselves. Without a deep sleep your immune system and metabolism in general are negatively affected. White and blue LED lights also make the dark seem even darker because the eye cannot flex quickly enough to see beyond the white/blue into the dark. This allows more hiding areas for both predators and thieves. Also white lights and LED’s around plants and over water perpetuate the growth cycle of plants resulting in more algae in a lake, and plants that don’t ever rest. This type of lighting also confuses and changes the mating cycles of amphibians and other wildlife. Because white and blue lights at night mimic dusk they attract predators but also mosquitoes! Finally, white and blue lights seem like stars to birds, other aerial flyers, and even turtles that navigate by them. Therefore these lights confuse and alter migration patterns putting these species at risk of exhaustion from disorientation.
- If you have white lights, an orange or red filter (easily found at auto parts stores to repair car signal lights) will help reduce the harm caused by night lights to yourself and to wildlife…and they will also extend your view! But the best is to choose low wattage amber bulbs becasuse LED’s are hard to filter. Why orange and red? Because the eye does not have to flex and adjust as much from light to dark when the light is orange or red. Remember fog lights? The orange penetrates into the dark and the fog. The eye can see a greater distance at night with orange or red lighting- it is closer in hue to the dark and so the eye can adjust easily. Again, your body, other wildlife and plants too, will not confuse orange or red lights with daylight, dusk, or with stars and the moon.
- Use cut-off fixtures: these are fixtures that direct lighting to where it is needed (usually down to the ground) and do not let light escape or pollute the sky or your neighbour’s properties.
- Use sensors or timers: easy fixes to get lighting only when it is needed.
Thanks to Dr. Robert Dick of the Royal Astronomical Society of Canada, Guidelines for outdoor lighting have been published to assist us with getting enough REM sleep and rest, with stewarding and saving our wildlife, and also affording navigation and protection around our properties!