Two Burmese fishermen were found floating in a bathtub-sized icebox off the Australia coast. They told authorities that they had spent 25 days adrift after their fishing boat sank, officials said. There was no sign of 18 other crew members.

The men, rescued on Saturday, apparently lived on monsoon water, fish chunks stored in the icebox and the vomit of sea birds, according to reports.

Authorities were amazed that the men, from the Southeast Asian nation of Myanmar, formerly Burma, were spotted by a routine customs-service flight that patrols for far larger craft.

Tracey Jiggins, a spokeswoman for the Australian Maritime Safety Authority, said: ‘They [the pilots] went back and had a look and realized it was two people.’ She said that the men were standing shoulder to shoulder in a large icebox ‘about the size of a chest freezer’. The men waved colored clothes at the aircraft to attract attention.

A helicopter was sent to pick up the men. Once rescued, the two men gulped down about half a gallon of water each, the pilot, Terry Gadenne, told a local radio station.

‘They were certainly thirsty,’ Mr. Gadenne said. ‘They had some boils or damage of some sort to their legs, and that was given first aid, and we flew straight to hospital from there.’

The men told police that they had been aboard a 30ft wooden fishing boat that sank on December 23 last year with a total crew of 20 from Thailand and Myanmar.