Breeds on small offshore islands (BirdLife International 2001). Forages in the breeding, passage and non-breeding seasons mostly in coastal wetlands including estuarine marshes, mangroves, tidal mudflats and sandflats, costal lagoons and bays. Also uses salt pans, tidal rivers and rice paddies.

This species is endemic to the East Asian-Australasian Flyway, where it breeds in four countries. In China, it mostly breeds in Changhai County on a series of small islands off the mainland. Breeding populations can also be found in adjacent North Korea and South Korea, with birds breeding on islands and often using nearby wetlands on the mainland for foraging. There is a small breeding population (comprising only c. 20 pairs) in extreme southeastern Russia in southern Primorye. The species previously bred in Taiwan (China) and Hong Kong (China) (BirdLife International 2001).

Birds winter to the south, particularly in the Philippines (key wintering areas are found on Leyte, Bohol and Cebu) and Malaysia (particularly Sarawak and Selangor; see Li 2006). Smaller numbers also winter in Kalimantan, northern Sulawesi and eastern Sumatra (Indonesia), coastal Myanmar, Thailand, Cambodia and Viet Nam, with small numbers recently found wintering in the Andaman Islands (India) (BirdLife International 2001, eBird 2025). On passage, this species occurs throughout coastal China (including Hong Kong and Taiwan). Recent GPS tracking surveys (Huang et al. 2022) have found that birds may migrate far inland, occasionally stopping at inland wetlands, including in landlocked Lao PDR.

Conservation Actions Underway
Listed in CMS Appendix I. It is legally protected in Russia, China (including Hong Kong), Taiwan, and South Korea. Some important breeding, staging and wintering sites are protected, including the Far Eastern Marine Reserve (Russia) and sites in China, including Hong Kong, Taiwan, North Korea, South Korea, Viet Nam and the Philippines. There has been a substantial increase in the number of volunteer groups and NGOs helping to monitor the migrations of shorebirds and other waterbirds, as well as increased media coverage and special events, demonstrating enhanced awareness among coastal communities (see also EAAFP 2016). North Korea became a Party to the Ramsar Convention and joined the EAAF Partnership in 2018. In 2021, the 'Regional Flyway Initiative' (RFI) was set up by the Asian Development Bank, with technical support from BirdLife International, with the aim of protecting and restoring priority wetland ecosystems and the associated ecosystem services they provide in the East-Asian Australasian Flyway (EAAF), the most threatened flyway globally. The Initiative is slated for implementation in 10 East, South and Southeast Asian countries. The RFI will mobilise large-scale financing to support the protection, sustainable management and restoration of at least 50 priority wetlands across ten Asian countries, with an initial financing commitment of $3 billion from the ADB (BirdLife International 2022). Over time, the RFI aims to enhance and expand the existing efforts in conserving and managing priority wetlands identified on the basis of supporting globally significant congregations of migratory waterbirds, and leverage on collaborative opportunities with stakeholders including national governments, civil society organisations, communities, regional organisations like the East Asian-Australasian Flyway Partnership.

Conservation Actions Proposed
Global population trends are poorly resolved in this species despite being covered by various monitoring schemes (e.g. the International Waterbird Census); filling this knowledge gap should be a priority. Protect existing breeding colonies from threats (e.g. hunting) and monitor rates of breeding success.