The impact of artificial light on birds and wildlife is a subject not too often talked about even though it represents a real concern for environmentalists.
Back in 2007, Tiffany Saleh, an Environmental Studies graduate student at the University of Montana, wrote the following concerning the effects of artificial light on wildlife: “The effects of ecological light pollution are widespread. They include disorientation from and attraction to artificial light, structural-related mortality due to disorientation, and effects on the light-sensitive cycles of many species.”
Miss Saleh also explains how artificial light can cause disorientation and even mortality. “Exposure to artificial light can create problems for species adapted to using light – or the absence of light – to aid in orientation. In these cases, ecological light pollution may interrupt natural behaviors, expose individuals to higher predation levels, or disrupt navigational abilities.”
And here is what she had to say about mortality: “Lighting produced and compounded by human structures can result in high mortality rates of wildlife living around them. This effect is related to disorientation, but specific to structures such as lighthouses, skyscrapers and street lamps.”
Concerning the behavioral responses of migrating birds to different lighting systems on tall towers, Sidney A. Gauthreaux, Jr. and Carroll G. Belser, from the Department of Biological Sciences of Clemson University, wrote “As early as 1886, E.A. Gastman reported that nearly 1,000 migratory birds were killed around electric light towers in Decatur, Illinois on a single evening. Exactly 110 years later, a report for World Wildlife Fund Canada and the Fatal Light Awareness Program detailed the hazards of lighted structures and windows to migrating birds. In an effort to understand why birds are attracted to lights and to assess the influences of different types of warning light arrays on towers, we examined the behavior of nocturnal migrants flying near tall towers with different types of lighting.”
Among their findings: “While birds in linear flight spend only a brief instant near the tower and leave the area, birds showing curved, circling, or hovering behavior spend more time near the tower and thus build concentrations of migrants in the area. Once concentrations build, the birds themselves may become collision hazards to other birds.”
After reading this, we have a better idea of how light does and can affect wildlife populations. So what can we do in order to improve the situation and minimize the effects our work as professionals in outdoor lighting can have on wildlife?
There are several cities in North America that have made the choice to participate in the “Lights Out” program. The city of Toronto takes this problem very seriously and is a great advocate for this program. Lights out Chicago is a voluntary partnership effort that saves more than ten thousand birds each year. Chicago is the first U.S. city to dim tall building lights to saved birds’ lives. In this program, building managers either dim or completely turn off the lights in tall buildings such as Chicago’s John Hancock Tower during the spring and fall bird migration seasons. It is important to specify here that since this program was first instituted, there has been a dramatic decrease in bird mortality around tall buildings, hence showing that this program does work and has shown beneficial effects.
There are other solutions which include replacing bare bulbs or any light pointing directly upward. In many situations, the amount of light used is at a much higher intensity than is necessary. The fact of dimming the lights or using a lower-intensity lighting source, while still maintaining the proper amount of light to allow humans to see and navigate safely, can also decrease the impact of artificial light on wildlife populations.
UrbanScape and MetroScape, two of Philips Lumec’s latest lighting solutions, were designed to minimize their impact on wildlife by using flat lens, hence no up light. Let us specify also that these products can also be combined with controls to minimize light use during the night in such a way that they minimize the impact on wildlife. That is what eco conscious products are all about.