Since it was first given a scientific name (Sterna bernsteini) in 1863, there had been only five confirmed sightings of this bird, and the last two-in Thailand in 1980 and in China's Yellow River delta in 1991-were not confirmed.
自一八六三年被正式命名之後，只有五筆。然而最近兩次一九八○年在泰國與一九九一年中國黃河三角洲雖都傳聞有所發現，但未被證實。