Efforts to preserve the native dabchick have been given a shot in the arm after a recent census of bird numbers at Lake Wairarapa.
A count on one day in July revealed 281 of the endangered wetland bird.
Only 2000 are estimated to be in existence and comparable counts on the lake between 1984 and 1994 put their number at less than 50.
"281 birds represents a surprising increase in the population," said Greater Wellington Regional Council spokeswoman Philippa Crisp.
The survey of the 18km of shoreline logged 6773 waterfowl belonging to 26 different species.
Other endangered species tallied included black-billed gulls, Australasian bitterns and black-fronted terns.