The issue is the focus for World Migratory Bird Day, held next Saturday, April 14, under the theme “Dim the lights for birds at night.”
Light pollution is on the rise, with artificially lit outdoor spaces rising 2.2 percent per year between 2012 and 2016, according to a study cited by the Secretariat of the Convention on Migratory Species of Wild Animals (CMS), a UN environmental treaty.
Currently, it is estimated that more than 80 percent of the world’s population lives under “illuminated skies”, and in Europe and North America this figure is closer to 99 percent.
Changing natural patterns
“Natural darkness, like clean water, air and soil, has a conservation value† An important goal of World Migratory Bird Day 2022 is to raise awareness about the problem of light pollution and its negative effects on migratory birds,” said Amy Fraenkel, Executive Secretary of CMS.
Artificial light alters natural patterns of light and dark in ecosystems and contributes to the death of millions of birds each year.
Light pollution can cause birds to change their migration patterns, foraging behavior and vocal communication, resulting in disorientation and collisions.
Disorientation and death
Migratory birds are attracted to artificial light at night – especially in low cloud, fog, rain or when flying at lower altitudes – luring them to dangers in cities.
Birds become disoriented and may begin to circle in lit areas. Now that their energy reserves are depleted, they risk being depleted, or worse.
“Many nocturnal migratory birds such as ducks, geese, plovers, sandpipers and songbirds are affected by light pollution, leading to disorientation and fatal collisions,” said Jacques Trouvilliez, executive secretary of the African-Eurasian Waterbird Agreement (AEWA), another UN -agreement. †
“Seabirds such as petrels and shearwaters are attracted to artificial light on land and become prey to rats and cats.”
Two years ago, countries that are parties to the CMS adopted light pollution guidelines for sea turtles, seabirds and migratory shorebirds.
The recommendations call for environmental impact assessments to be carried out for projects that may lead to light pollution.
Projects should take into account the main sources of light pollution in a given location, the potential encroachment of wild species and facts about the proximity of important habitats and migratory routes.
New guidelines targeting migratory terrestrial birds and bats are currently being developed and will be presented for approval at a CMS conference next year.
Solutions for light pollution are readily available, Ms Frankel said. According to the United Nations Environment Program (UNEP), more and more cities around the world are taking measures to dim the lighting of buildings during migration phases in the spring and autumn.
Call to action
World Migratory Bird Day is celebrated twice a year, on the second Saturday in May and October, in recognition of the cyclical nature of bird migration and the different peak periods in the Northern and Southern Hemispheres.
It is organized by a partnership between the two UN nature conventions and the non-profit Environment for the Americas (EFTA).
“World Migratory Bird Day is a call to action for the conservation of international migratory birds,” said Susan Bonfield, the EVA director.
“As migratory birds traveling across borders inspiring and connecting people along the way, our goal is to use the two days in 2022 to raise awareness about the threat of light pollution and the importance of dark skies to bird migrations.”