The Chilbaldo Islet in Republic of Korea was designated in the Flyway Site Network (FSN) as first internationally important seabird habitat on 9 November 2011. The site is a breeding site for seabirds, Swinhoe’s Storm-Petrel (Oceanodroma monorhis), Streaked Shearwater (Calonectris leucomelas) and Ancient Murrelet (Synthliboramphus antiquus), and is also a stopover site for migratory passerines, raptors – 137 bird species were recorded including 4 internationally vulnerable and 17 nationally protected birds. The site meets FSN criteria for seabird species with high numbers of Swinhoe’s Strom-Petrels about 26,000 birds. Internationally Chilbaldo is also included within the boundary of Shinan Dadohae Biosphere Reserve designated by UNESCO after 2009.