Police say a Brisbane man managed to survive being in the water for 15 hours and another man about 10 hours after their boat capsized.
A search continues for another man who was onboard.
It is understood the three men had left on a seven-metre Goodwin Longboat on for a fishing trip on Tuesday.
Whitsunday Water Police officer Syrrell Howard said an EPIRB was triggered about 8pm on Thursday, speaking a multi-agency search and rescue operation.
The Australian Maritme Safety Authority was alerted and raised the alarm with police, CQ Rescue and the Mackay Volunteer Marine Service.
The Bray Park man, 43, was one of two men to be found and retrieved at Creal Reef on Friday, about 150 kilometres from the coast of Mackay.
Remote spot
Senior Constable Howard said the EPIRB's alert was issued 85 nautical miles from shore — which would take up to six-and-a-half hours to reach by boat.
"That gives you an idea of how remote the location is," he said.
He said a rescue helicopter sighted a man late last night clinging to the hull of an overturned vessel.
"As they got closer it appears that for some unknown reason the man has become detached from the vessel, and then they tried to reposition their aircraft and were unable to see him again," he said.
It is understood the rescue helicopter was forced to turn back to shore to refuel.
"Fortunately at 5.50am we received information that a male had been recovered from the water," Senior Constable Howard said.
He said an aircraft spotted a 44-year-old man from Grasstree Beach and was able to direct a marine rescue vessell to retrieve him.
He said there were reports the man was in a critical condition and a medic crew was flown in before he was eventually flown to Mackay Base Hospital.
The second man, 43, was found at 11.10am.
CQ Rescue crews winched down from a helicopter to pull him from the water.
The man told the rescue crew that there was a third man, a younger brother to the first survivor, still missing.
The 43-year-old man was flown to Mackay Base Hospital.
Senior Constable Howard said the accuracy of the information from the 43-year-old had been inconsistent but hoped more would become clear as he recovered.
An AMSA spokesperson said a search and rescue operation to locate the 41-year-old missing brother was ongoing.
They said the Cairns-based Challenger, Townsville-based Rescue Helicopter 521, Mackay-based Rescue Helicopter RSCU412, a Mackay-based pilot transfer helicopter and a local fishing vessel were a part of the search.
Clinging to hull
A CQ Rescue spokeswoman said the 43-year-old man had reported that a wave had overturned the trio's boat.
"All three were in the water after the boat sank and the two brothers tied themselves to a blue esky," the spokeswoman said.
"They have somehow all become separated."
She said the 43-year-old was spotted by CQ Rescue floating with no life jacket and no clothes on.
"He is suffering exposure, dehydration, hypothermia after being in the water since 8.30pm last night," she said.
The two rescued men remain in Mackay Base Hospital in a stable condition.
