The Effects of Light Pollution on Migrating Birds

Millions of songbirds fly over Miami every spring and fall as they migrate along the Atlantic Flyway between their nesting habitat to the north and their wintering habitat to the south. Songbirds typically migrate at night so they can take advantage of cooler temperatures and calmer air as well as avoid being eaten by hawks and other diurnal birds of prey. These nocturnal migrants use a variety of navigational aids, including magnetic fields and the stars, to keep them on course. To learn how modern technology is allowing us to better understand nocturnal bird migration, click here.

Migrant songbirds flying at night over brightly lit cities are often unable to use the stars as a navigational aid. The bright lights of tall buildings may also disorient birds, forcing them off course or making it more likely that they’ll collide with a building. Hundreds of millions of birds are killed each year in the United States due to collisions with buildings and other man-made structures. This video produced by the Cornell Lab of Ornithology illustrates the problem. To learn more about how bright lights disorient migrating birds, click here.

To get a sense of how many birds are killed in Miami each year by collisions with buildings, Tropical Audubon Society has, as part of our Lights Out Miami program, organized and implemented a bird collision monitoring campaign within Miami-Dade County. Other components of this initiative include a campaign to encourage building managers and homeowners within the county to turn off unnecessary lights during the spring and fall bird migration seasons. We’ll also advocate for legislation such as the Bird-Safe Buildings Act that requires the use of building products that prevent bird collisions and encourage homeowners to apply anti-collision decals to their windows.

Audubon’s Lights Out Program

National Audubon Society’s Lights Out program, a component of its Bird-Friendly Buildings initiative, aims to raise awareness of the dangers that urban lights pose for migrating birds. Local Lights Out programs are currently operating in 48 cities in the United States. There are also five state-wide or regional programs. A summary of recent Lights Out achievements is here.

Audubon and partners created the first Lights Out program in Chicago in 1999. The Chicago program was modeled after the Fatal Light Awareness Program (FLAP), created in Toronto in 1993. To learn how Lights Out programs got started in other cities, including Miami, click here.

In 2020, Audubon launched a partnership with Dark Sky International, combining Audubon’s bird migration knowledge with IDA’s light pollution technical expertise to join forces to reduce light pollution, benefitting both birds, other wildlife and us. Since the launch of Lights Out Miami in 2021, Tropical Audubon Society has been an active participant in local programming during International Dark Sky Week, which takes place every April during the peak of spring migration in south Florida.

Bird Collision Monitoring Campaign

Bird collision data collection in Miami-Dade County commenced in Fall, 2021. In addition to giving us a sense of the scope of bird mortality in the county as a result of collisions with buildings, the data collected during this campaign should also help us to better understand which bird species migrating over Miami are most likely to collide with buildings, the time of year or time of day when collisions are most likely to occur and the types of building lights or windows that are most likely to result in collisions.

Volunteers are needed to search for birds that have been killed or injured after colliding with buildings. Though data can be collected anywhere in the county, even around your home, we especially need volunteers willing to survey the downtown Miami area and other locations with many tall buildings where significant numbers of bird collisions are most likely. Volunteers submit the data they collect via dBird, a database developed by New York City Audubon and later expanded by Seattle Audubon. Though bird carcasses will not be collected during this campaign, volunteers are strongly encouraged to transport any injured birds encountered to a local wildlife rehabilitation facility.

Click on the buttons below if you wish to volunteer to collect bird collision data in Miami-Dade County, or to submit bird collision data to dBird. If you have questions regarding our Bird Collision Monitoring Campaign, contact Brian Rapoza at fieldtrips@tropicalaudubon.org.

Reducing Bird Mortality Due To Light Pollution

Tropical Audubon Society encourages all homeowners and commercial building managers in Miami-Dade County to join our Lights Out Miami campaign by pledging to reduce bird collisions with buildings during spring migration (March 15 to May 15) and fall migration (August 15 to November 15) by taking the following simple steps to reduce lighting:

• Turning off unnecessary lighting (especially the upper floors) between 11 p.m. and sunrise

• Put lights on timers

• Utilize motion sensors on lights

• Make sure external lighting is down-shielded

• Close shades or blinds

• Dim or turn off lobby or atrium lighting

• Use strobe lighting when appropriate

Reducing Daytime Window Collisions

During daylight hours, many songbirds have difficulty distinguishing the window reflections of trees and other foliage from the actual trees and foliage that they use to nest or forage for food. As a result, they end up colliding with windows, often fatally. A number of steps can be taken by homeowners and other building owners to reduce the likelihood of bird collisions with windows, including installing bird-safe glass or applying a thin adhesive film with reflective patterns visible to birds onto each window. For example, Feather Friendly® anti-collision decals have been shown to be highly effective in preventing window collisions and are approved by both Audubon and the American Bird Conservancy.

Doc Thomas House’s circa 1932 front porch mullion windows are now sporting anti-collision Feather Friendly® decals, serving as a model for raising awareness about preventing deadly bird strikes (most often associated with plain glass windows and doors). The life-saving decals were installed by TAS Board members Eliana Ardila Kramer and Marc Kramer (pictured). The “Birding by Bus” cofounders are also Feather Friendly® ambassadors who have mounted a South Florida effort to educate the public about the little-recognized crisis of soaring bird deaths caused by glass windows that are invisible to birds in flight. Raising awareness and compelling action is particularly crucial in Greater Miami, where glass-plated high-rise buildings are common, and are directly in the path of migrating birds traveling along the Atlantic Flyway.