Key Biodiversity The site is one of Thailand's most important freshwater wetlands, which supports large numbers of both resident and wintering waterbirds annually. The site holds a substantial wintering population of the globally threatened Baer's Pochard Aythya baeri; the highest counts of the species constitute greater than 1% of the Asian biogeographic population. Several other globally threatened species have been recorded at the site, including Baikal Teal Anas formosa, Greater Spotted Eagle Aquila clanga and Spot-billed Pelican Pelecanus philippensis, although none are known to regularly occur in significant numbers. Furthermore, five globally near-threatened species have been recently recorded at the site: Ferruginous Pochard Aythya nyroca, Oriental Darter Anhinga melanogaster, Painted Stork Mycteria leucocephala, Black-headed Ibis Threskiornis melanocephalus and Asian Golden Weaver Ploceus hypoxanthus. Bung Boraphet is the only site in the world where the enigmatic White-eyed River Martin Pseudochelidon sirintarae has been recorded. However, there have been no confirmed records of this globally critical species since 1978, and there is no indication that it still persists at the site. There are also historical records of the globally endangered Greater Adjutant Leptoptilos dubius from the site in the late 1980s. Again, there is no indication of the continued occurrence of the species. The site regularly supports greater than 20,000 waterbirds: counts of 36,000 and 20,060 waterbirds were made in 1991 and 1994, respectively. The commonest waterbird species known to breed at the site include Pheasant-tailed Jacana Hydrophasianus chirurgus, Purple Swamphen Porphyrio porphyrio and Asian Openbill Anastomus oscitans; the site supports over 1% of the Asian biogeographic population of the latter species.