Intertidal Flats of East and Southeast Asia

Abstract

A recent rise in economic prosperity in Asia, the most densely populated region of the world, has created a shortage of land for industry, housing developments and aquaculture. Consequently, large extents of tidal flat habitat in East and Southeast Asia, and especially in the Yellow Sea, have been lost since 1980, some through sediment inflow reduction, some through reclamation to satisfy demand for land. Throughout the East Asian-Australasian Flyway (EAAF), over 600,000 ha of tidal flats were the subject of further proposed land claims in 2012; in the Yellow Sea, planned conversions of >300,000 ha would amount to a further loss of 40% of the remaining habitat. Here we articulate five arguments to contribute to convincing governments and other stakeholders in the EAAF that the current rate of loss is a disaster which must be urgently addressed. (1) Global responsibility: the EAAF is a large flyway supporting 176 waterbird species, of which 34 (19%) are globally threatened or Near Threatened. Nine more species are under consideration for such listing. Other flyways have 5-13 threatened species, amounting to 4-12%. (2) Regional responsibility: migratory shorebird species essentially make a single stop, or very few stops, when moving between non-breeding and breeding sites. In the EAAF, most of these critical sites where birds refuel for a few weeks are in the Yellow Sea. (3) Regional effects: shorebird population trends in Japan, and at a single wintering site in Australia showed that shorebirds dependent on the Yellow Sea during migration show the strongest population declines. (4) Local effects: migratory shorebirds that lost their fuelling site due to the largest land claim projects in the Yellow Sea (Saemangeum and Bohai Bay) did not all redistribute to the adjacent tidal flats, resulting in a net population decline. (5) Self-interest: Tidal flats and associated coastal ecosystems provide critical ecosystem services including protection from storm surges and sea level rise. This information was summarized in a 2012 IUCN report and subsequently EAAF governments have committed via IUCN Resolution 28 to protect the EAAF.