Ecological Light Pollution“Artificial light that alters the natural patterns of light and dark
in an ecosystem”
Various forms of light pollution:•Lighted buildings•Street lights•Car head lights•Neon signs
Effects the following aspects of a variety of animal and insect species:•Behavior•Communication•Foraging•Reproduction
New York City (photo by broddi)PowerPoint Created by: Christie Christakos
BehaviorEcological trap = the environment changes faster than a species has time to
react and adapt to it
Arthropods (dragonfly, lacewing beetles, wasps, and crickets) can misconstrue dark buildings, asphalt roads, glass windows, and cars for water
because polarized light reflects off these surfaces (possibly causing their death)
“Aquatic insects are the foundation of many food webs. Therefore, reductions in their numbers may alter entire ecosystems and the services they provide”.
(Ecological Society of America 2009)
Dragonfly (photo by BluAlien)
Communication
Lampyridae (fireflies or glow-worms)• Use bioluminescent flashes as a form of sexual communication• Artificial light reduces the males’ visibility of the females’ signal
Predator-Prey Relationships• unexpected change in artificial light levels benefits predators whose prey is
attracted to lightex. Bats prey on insects, such as tympanate moths, which are
attracted to light• Researchers attribute light pollution as the main cause of the decrease of North
American moths
Lampyriade (photo by Say~cheese) Moths attracted to light (photo by Mudeth)
Reproduction• Singing is a way for male birds to attract female birds
Turdus Migratoius (photo by cosmicsailor)
Turdus migratorius (American Robin) begin to sing their “morning chorus” earlier in the day in areas with a low level of artificial light
Foraging•An unexpected change in light pollution leads to an increase in foraging time for species that forage during the day, which may increase predation
(Longcore 2004)
What is NYC doing to reduce light pollution?
National Dark Sky Week• occurs on the week of the new moon in April since a full moon increases
the light pollution (Barlow 2003)• people are asked to reduce their artificial lighting usage and turn off any
unnecessary lights as a way of appreciating the sky and raising awareness
Energy Efficient Lighting Tactics• Motion sensor lights in unoccupied rooms• Reduction of neon signs and unshielded traffic lights
Times Square (Photo by Toni Shi)
Bibliography
• Barlow, Jennifer. 2003-2009. Natural Dark Sky Week. http://www.ndsw.org/• Longcore, Travis, and Catherine Rich. "Ecological light pollution." Frontiers
in Ecology & the Environment 2, no. 4 (May 2004): 191-198. Environment Complete, EBSCOhost (accessed February 7, 2009).
• Ecological Society of America. 2009. Polarized Light Leads Animals Astray: 'Ecological Traps' Cause Animal Behaviors That Can Lead To Death.