The Dark Problem of Light Pollution

Light pollution is the result of using artificial lighting during the night, illuminating our environment after the sun sets. Street lights, light coming from the inside buildings, flood lights on homes, parking lots or stadiums, LED billboards or signs, car lights, and lights on communications towers are all major contributors to light pollution.   

Thanks to the invention of electricity, we are able to speak to other people across the world, cook food, charge our phones and computers, and light up homes in an instant. But, with this great power comes responsibility to be aware of our actions and their consequences, particularly how lights affect animals at night.  A snapshot of negative effects can be found in the table below.

Light Pollution Issues and Effects
Issue Negative Affect Animals Affected
Disrupted sleep cycle   Light Pollution creates excess light which disrupts their sleep cycle. This in turn interrupts other biological activities including breeding and hunting. Light pollution disrupts their sleeping patterns thus making their ability to attract mates more difficult due to nocturnal animals sleeping later than usual and having less time awake. This ultimately creates a problem  because they unable to find possible mates, have a difficult time getting food due to sleeping later than normal thus having less time to find food, and become more vulnerable to predators, which in turn reduces population.

But even diurnal animals, creatures that sleep at night and are active during the day, are affected by light pollution. Their environment is artificially lit, even when night comes. hese animals do not realize that it is time to sleep and remain awake for longer than what is natural. This causes a disruption in their sleeping patterns which may make them more vulnerable to predators due to sleep deprivation.   

Nocturnal Animals: Raccoons, Toads, Owls, Bats, Opossum, Coyote, Mouse, Fox

Diurnal Animals:

Squirrels, Falcons, Horses, Bearded Dragons, Rabbits

Inability to navigate; disorientation Birds that hunt or migrate during the night are also greatly affected by light pollution. Birds use the light of the moon to find their prey and to migrate long distances. However, light pollution causes these birds to lose track of their destination or even migrate too early or too late in the season. Birds use the light of the stars and moon for navigating at night; but, because of an excess of artificial light, their route can be misconstrued. e lights and decorations on the buildings can cause birds to become disoriented, aimlessly circle, and  ultimately settle in a city park, street or bush. Birds can also die by flying into buildings because of the reflections from lights. These factors ultimately diminish their population drastically. Nocturnal Migrating Birds: Cuckoos, Sparrows, Warblers, Flycatchers
Sea turtles lose their way and die Sea turtles are not nocturnal but during their breeding season, they populate the beaches and locate an area suitable to lay their eggs.  The eggs also hatch during the night, and when they dig themselves out of the sand, they use the light of the moon to guide them to the ocean. However, light pollution can lure these small turtles toward a different light source, such as flood lights, flashlights, street lights and lighted  displays. Many of them will die because they are unable to find the ocean. Sea Turtles


What is being done and what you can do to help

Many people are becoming more aware of the negative effects that light pollution has on animals and are attempting to put into practice action plans that can combat this issue.Some of these plans include enacting legislation about what type of lighting can be used in certain areas, and by replacing light bulbs with more energy efficient and less disruptive bulbs. You may use the BUG rating when selecting the best bulbs to minimize light pollution. BUG rating stands for blacklight, uplight and glare and lets users know how much BUG a bulb emits. Lighting ordinances are being put into place throughout communities to ensure a better, safer environment for animals. You can advocate to your local government to instill a lighting ordinance if there is not one currently in place. The International Dark Sky Association created official IDA seals of approval to be placed on various lighting products that are sure to minimize light pollution.

Some easy ways you can help reduce light pollution is by turning off outside and inside lights around your house at night when the lights not being used. You can share with your friends and family the information you learned in this article about the effects light pollution has on animals. You can come together as a community to survey your town and make note of where lights are not needed. Replace light bulbs with IDA approved lights and you can use timers, motion sensors and dimmers whenever possible are also beneficial Following these easy suggestions allow you to help reduce light pollution and give animals affected by artificial lighting, a voice.

Sources:, American Association for the Advancement of Science, Conserve Energy Future, International Dark-Sky Association, A Journal of the Built + Natural Environments.