Sonadia Island is a low-lying barrier island covering approximately 9,800 hectares along the southeastern coast of Bangladesh in Cox’s Bazar District, Chattogram Division. The site comprises a diverse mosaic of coastal and estuarine habitats, including intertidal mudflats, sand beaches and dunes, salt marshes, lagoons, shallow marine waters, and the last remaining natural mangrove forests in southeast Bangladesh. These habitats support internationally significant populations of migratory waterbirds, most notably the Critically Endangered Spoon-billed Sandpiper, as well as other threatened species such as the Spotted Greenshank. Sonadia Island is designated as an Ecologically Critical Area and has been recognized as a Flyway Network Site under the East Asian–Australasian Flyway Partnership since 2011.

 

The wetlands of Sonadia Island provide vital ecosystem services, including coastal protection and fishery resources that underpin local livelihoods for an estimated 12,000 people across five villages. Communities depend heavily on small-scale fishing, shrimp collection, salt farming, and seasonal agriculture. However, the site faces increasing pressure from unsustainable fishing practices, marine plastic pollution, the expansion of settlements and commercial activities, and climate-related risks such as sea-level rise and storm surges. Opportunities for Regional Flyway Initiative interventions include strengthening site management and zoning, restoring and protecting critical habitats, improving waste and pollution management, promoting sustainable coastal fisheries, and developing carefully managed ecotourism to diversify livelihoods while safeguarding biodiversity.