Scientists have studied how light pollution affects the visual orientation of wildlife. Birds that rely on constellations as a guide during migration are led off course by artificial light around urban areas. The artificial light confuses birds, upsets their natural steering ability and results in deadly collisions with towers and smokestacks. Researchers see similar effects of light pollution in sea turtle hatchlings. The natural glow of the horizon usually signals turtles toward the water, but competing artificial light from beachfront properties can cause them to head inland. Hatchlings are vulnerable to passing cars and predators.
Artificial light disrupts natural patterns of light and dark, according to Ecological Light Pollution in Frontiers in Ecology, a review published in the Ecological Society of American. Glare produced by artificial light affects foraging, communication and other critical behaviors. Researchers are beginning to seeing how light pollution affects reproduction, citing dragonflies as an example. An article at New Scientist.com says dragonflies are attracted to the glare of road pavement. The insects lay their eggs on car hoods, a location where eggs are less likely to hatch. Scientists believe the effects may cascade up the food chain.
On a positive note, a growing number of people are recognizing the effects of light pollution on the environment. Scientists, astronomers, naturalists have been educating the public about the effects of light pollution. Now state and local government agencies are trying to reduce light pollution through legislation. Engineers and architects and other members of the lighting design community are making efforts to limit light pollution with more efficient fixtures.