RAYMOND, Miss. -- Lighting has increased human productivity by extending the functional time during a given day to work, play and relax. Exterior lighting for streets and walkways allows us to safely enjoy our cities and communities during the evening hours, which is especially pleasant during the hot summer months in Mississippi.

Unfortunately, this convenience has come at a cost for some wildlife species. Man-made light has been shown to disrupt animal behavior, including activities such as migration, feeding and breeding. Artificial lighting also has been known to make animals avoid their typical habitats.

Adam Rohnke

Migrating birds can become disoriented at night from the glow of light over metropolitan areas. The unnatural light washes out the horizon and other key geographical markers birds use to navigate. As a result, the affected birds circle the area continuously to the point of exhaustion. In some cases, they actually collide with the lighted objects, such as tall office buildings.

Exterior home lighting can be just as dangerous. Insect-eating animals, such as bats and tree frogs, often feed on insects that are drawn to outside lights at residences. Although this activity can provide an excellent opportunity to see secretive animals in action, the situation can lead to more of these critters being killed by their own predators. 

Wildlife and light interactions also can lead to direct human-wildlife conflict issues.  

Some of these interactions are common and harmless, such as the midnight singing of a light-stimulated Mockingbird or an unexpected visit from a tree frog.

Other interactions should be taken more seriously, including incidents of birds striking lighted buildings or entering lighted carports and garages. Birds can become disoriented from garage lights and their reflection off the ceiling. In their confusion, birds can injure or kill themselves when they collide with walls. Homeowners often cause more harm by trying to help the injured bird. An injured and frightened bird also can injure the human trying to help it.

So, what can you do? Communities and homeowners can employ several strategies to reduce lighting impacts on wildlife. They include installing timers, using fewer exterior lights and turning off outside lights when not in use. Turn off overhead lights in carports and garages, and close garage doors at dusk.

When installing or retrofitting exterior lighting, follow a successful set of principles developed in other parts of the country called “Keep it Low, Keep it Shielded, and Keep it Long.”

Keep it Low: position lighting as low to the ground as possible to reduce its spread. 

Keep it Shielded: reduce the spread of each light fixture by installing shields on the tops and sides of fixtures.  

Keep it Long: use amber and red light bulbs that have less disorienting effects on wildlife while still providing useable light for human purposes.

By implementing these simple practices, you can enjoy the benefits of lighting while reducing its harm to Mississippi wildlife. For more information on the effects of lighting on other wildlife species, visit http://myfwc.com/conservation/you-conserve/lighting/.

Editor’s Note: Extension Outdoors is a column authored by several different experts in the Mississippi State University Extension Service.