The group spent six days without food or water on a remote island where they were shipwrecked by Cyclone Ilsa.

The Australian Maritime Safety Authority (AMSA), which rescued the fishermen on Monday night, said the group was recovering after being picked up from Bedwell Island, some 300km (200 miles) west of the Australian coastal tourist town of Broome.

One of the boats, Express 1, ran aground with 10 men on board on April 12, AMSA said in a statement on Wednesday.

The other, Putri Jaya, sank in “extreme weather conditions” on April 11 or 12, the authority said, with nine of the crew thought to have drowned. The only known survivor from Putri Jaya spent 30 hours in the water before reaching land at Bedwell, a remote, exposed and inhospitable stretch of white sand with no natural shelter or freshwater sources.

The survivors, who had built a makeshift shelter with debris from their boat, were spotted on Monday by the Australian Border Force, which was on a routine aerial surveillance mission. A Broome-based rescue helicopter was deployed and winched all 11 on board as the light began to fade.

Gordon Watt, a manager at helicopter provider PHI Aviation, said the rescue helicopter crew had been unable to land on the sand.

“They had to conduct winch recoveries which, in itself, is a challenging task,” Watt told the Australian Broadcasting Corporation (ABC). “The time of day meant that nightfall was upon the crew during the rescue, so they had to transition to using night vision goggles.”

The survivors were taken to Broome Hospital where authorities reported them in good health. They are expected to be flown back to Indonesia when they have recovered.

Ilsa gathered strength as it moved across the sea towards Australia and was a maximum Category 5 cyclone when it crossed the coast southwest of Broome unleashing some of the strongest winds the country has ever recorded.

No deaths or injuries from the storm were reported in Australia.