Governments, cities, businesses and communities around the world are taking action to address a significant and growing threat to wildlife, including many species of migratory birds: light pollution.
The question is at the center of World Migratory Bird Day, celebrated this Saturday, April 14, under the theme “Dim the lights for birds at night”.
According to a study cited by the Secretariat of the Convention on Migratory Species of Wild Animals (CMS), a United Nations environmental treaty.
Currently, it is estimated that more than 80% of the world’s population lives under “lit skies”, and this figure is closer to 99% in Europe and North America.
Modification of natural models
“Natural darkness has conservation value in the same way as clean water, air and soil. One of the main objectives of World Migratory Bird Day 2022 is to raise awareness of the problem of light pollution and its negative impacts on migratory birds,” mentioned Amy Fraenkel, CMS Executive Secretary.
Artificial light alters natural light and dark patterns in ecosystems and contributes to the death of millions of birds every year.
Light pollution can cause birds to change their migration patterns, foraging behaviors and vocal communication, leading to disorientation and collisions.
Disorientation and death
Migratory birds are attracted to artificial light at night – especially when there are low cloud conditions, fog, rain or when flying at low altitude – drawing them to hazards in cities .
Birds become disoriented and as a result may end up circling in lighted areas. With their energy reserves depleted, they risk exhaustion, or worse.
“Many nocturnal migratory birds such as ducks, geese, plovers, sandpipers and songbirds are affected by light pollution causing disorientation and collisions with fatal consequences,” said Jacques Trouvilliez, Executive Secretary of the African-Eurasian Waterbird Agreement (AEWA), another UN treaty. .
“Seabirds such as petrels and shearwaters are attracted to artificial lights on land and fall prey to rats and cats.”
A safer sky
Two years ago, CMS Party countries approved light pollution guidelines covering sea turtles, seabirds and migratory shorebirds.
The recommendations call for environmental impact assessments to be conducted for projects that could cause light pollution.
Projects should consider the main sources of light pollution at a given site, the wildlife species likely to be affected, and facts about proximity to important habitats and migration routes.
New guidelines focusing on migratory landbirds and bats are being developed and will be presented for adoption at a CMS conference next year.
Solutions to light pollution are readily available, Ms. Frankel said. More and more cities around the world are taking measures to dim the lighting of buildings during the migration phases in spring and autumn, according to the United Nations Environment Program (UNEP).
Call to action
World Migratory Bird Day is celebrated twice a year, on the second Saturday of May and October, in recognition of the cyclical nature of bird migration and the different peak migration times in the northern and southern hemispheres.
It is organized by a collaborative partnership between the two United Nations wildlife treaties and the non-profit organization, Environment for the Americas (EFTA).
“World Migratory Bird Day is a call to action for the international conservation of migratory birds,” said EFTA Director Susan Bonfield.
“As migrating birds travel across borders, inspiring and connecting people along the way, our goal is to use the two days in 2022 to raise awareness of the threat of light pollution and the importance of dark skies. for bird migrations.”