Pollution in the coastal wetlands of East Asia: Cascading effects from littoral macroinvertebrates to migrating shorebirds

Globally, coastal ecosystems are undergoing rapid changes with respect to habitat degradation and pollution, which is especially true along the East Asian coastline due to rapid industrial and urban development. This has led to effects on coastal wetlands in terms of biodiversity and also on the quality of the stopover sites for migrating birds, such as shorebirds. Shorebird populations are declining at an alarming rate along the East Asian Australasian flyway (EAAF), the reasons for which are currently unknown. The role of pollution in these declines, which is unknown, is suspected to play a role. One way that pollutants might decrease survival during migration may be via immunomodulative properties that can affect the susceptibility to disease. Pollution has indeed been related to the outbreaks of disease and increase in disease as early as the 1960s in animals, including birds, and humans. In this study, we aim to study the impact of pollution on the biodiversity of littoral macroinvertebrates in coastal wetlands in East Asia, and the resulting combined impact of food availability, pollution and disease on migrating shorebirds using these wetlands as stop-over sites. The potential combined impact of pollution and resultant disease on the fitness and decline of shorebirds has been neglected until now. The proposed project will pioneer investigations into the combined impact of pollution and disease on the decline of migratory shorebirds along the EAAF, with a specific focus on pollution picked up along the Chinese coastline during migration. As there is no information on the impact of pollution (in combination with other stressors e.g. lack of food, disease and high energetic demands during migration) on migratory shorebirds along the EAAF, nor in other flyways (e.g. the East-Atlantic Flyway), the results of the project will bring scientific renewal and will inform conservation and risk management measures for important stop-over ecosystems.