Dim night lights to save migratory birds

When cities glow artificially bright at night, the light pollution obscures the star-filled night sky. The World Migratory Bird Day being observed today is a grim warning to the global community that the loss of natural darkness is also affecting long distance winged visitors and disrupting their migration along their flyways. The 13thConference of the Parties (COP) to the Convention on Migratory Species hosted by India at Gandhinagar in 2020 flagged the issue of light pollution affecting migratory birds and other migratory wildlife species. The Gandhinagar COP acknowledged that both humans and wildlife need the "right light, in the right place, at the right time" and confirmed that "light pollution refers to artificial light that alters the natural patterns of light and dark in ecosystems." The Guidelines on management of light pollution at the conference, that provides a framework for assessing and managing the impact of artificial light on susceptible wildlife, notes that artificial light is also necessary for human safety or similar important public interests. It also acknowledged the challenges of balancing such requirements of artificial lights for humans and reducing the light pollution for conservation of migratory birds and other species and called for innovative solutions. The conference acknowledged that artificial light is increasing globally by at least two per cent annually and noted that there are many documented instances migratory shorebirds using less preferable roost sites to avoid lights, and disruption in foraging and fledgling for a number of seabirds. The global experts who discussed the issue in threadbare detail called for managing artificial light so that migratory species are not disrupted within, nor displaced from, important habitat, and are able to undertake critical behaviours such as foraging, reproduction and migration. The Conservation of Migratory Species of Wild Animals, African-Eurasian Migratory Waterbird Agreement, and Environment for the Americas ( EFTA) in their campaign strategy for observation of World Migratory Bird Day 2022, has focussed on the slogan – 'dim the light for birds at night'. "Light pollution can alter birds' behaviours, including migration, foraging and vocal communication. It also affects their activity levels and their energy expenditures. Migratory birds are particularly exposed to light pollution, especially those which migrate at night. Light pollution attracts and disorients nocturnally migrating birds, which may end up circling in illuminated areas. This unnatural light-induced behaviour can mean they end up depleting their energy reserves and puts them at risk of exhaustion, predation, and lethal collision," states the campaign strategy document. Many nocturnally migrating birds such as ducks, geese, plovers, sandpipers and songbirds of all kinds are affected by light pollution. Seabirds such as petrels and shearwaters commonly get drawn into hazardous situations on land and on ships by artificial light sources, it adds. Another key message for this global day campaign is: "Natural darkness has conservation value in the same way as clean water, air and soil, and should be protected." The migratory birds play critical role in conservation of the natural ecosystem by contributing to pollination, seed dispersal, help farmers by eating insects and rodents and thereby reducing expenditures in use of insecticides or rodent control, and helps communities to generate revenue from eco-tourism around birdwatching sites that receive long distance migratory birds. Apart from light pollution habitat degradation of habitats including wetlands, stopover sites and wintering sites have also posed threats to migratory birds. According to India's National Action Plan for Conservation of Migratory Birds and their Habitats along Central Asian Flyway (2018-2023) at least 370 species of migratory birds from three flyways – Central Asian Flyway, East Asian Australasian Flyway and Asian East African Flywayare reported to visit the Indian subcontinent, of which 310 predominantly use wetlands as habitats, the rest being landbirds, inhabiting dispersed terrestrial areas.Major stresses on population of migratory birds include habitat loss and degradation, pollution, illegal shooting and poisoning, collisions with aerial structures such as wind turbines, electrocution by power lines and increasing night light, highlights the National Action Plan. Deepor Beel on the outskirts of Guwahati city is a unique wetland and a Ramsar Site sustains about 60-70 migratory bird species. It calls for evaluating the impact of increasing night light during migration, collision and electrocution risks to migratory birds and recommend mitigation measures.While illegal encroachment, fragmentation of wetland landscape, dumping of municipal solid waste near the wetland have posed conservation threats to species dependent on the wetland including migratory birds, rapid expansion of the city has resulted in illumination of residential areas, airport, high mast flood lights adding to light pollution which call for urgent action by authorities concerned as well as city residents before it is too late. Observation of this global day needs to kickstart an intense campaign for reducing light pollution in cities calling upon government, civil societies for innovating result-oriented actions to achieve the objectives.