All search and rescue efforts to find a missing boatie 200 kilometres off the coast of Mackay have been suspended. 

Two brothers and their friend left on a fishing trip to Creal Reef on Tuesday last week but activated an emergency beacon at around 8pm on Thursday, sparking an intense search operation. 

Multiple agencies including police, CQ Rescue and the Mackay Volunteer Marine Service have spent the last four nights and three days searching remote waters. 

Initial reports were that a boat with two people on board had capsized 85 nautical miles from where they departed at the Mackay Marina.

However, after two men were located alive, police were alerted to a third person still missing. 

A 43-year-old man from Brisbane managed to survive in the water for 15 hours, while a 44-year-old man from Grasstree Beach survived for 10 hours. 

There has been no trace of the 41-year-old man, who is a brother to the 44-year-old man. 

Speaking on Monday, Inspector Andrew Godbold said all search and rescue efforts had been suspended. 

"Using the information that we've got from our experts we estimated probably a-day-and-a-half to two days was about the most you could stay alive out there," he said. 

"We've had eight to 15 boats at different times out there searching, as well as a number of aircraft and helicopters. 

"The huge difficulty is that it is so far off [the coast] that by the time we get planes and helicopters out there they have to turn around and come back and similar with the boats as well."

Inspector Godbold said the missing man's family were devastated. 

"They've lost one of their sons and it's a terrible time for them."

According to initial reports, a large wave overturned the trio's boat. 

A CQ Rescue spokeswoman said all three men were in the water as the boat was sinking and the two brothers tied themselves to a blue esky. 

"They have somehow all become separated."

CQ Rescue reported sighting one of the men clinging to the hull of an overturned vessel at around midnight on Thursday. 

A spokeswoman said as they got closer, the man could no longer be seen, and the helicopter had to turn back for fuel. 

At first light an AMSAR jet spotted a 44-year-old Grasstree Beach man clinging to the upturned fishing boat. 

The man was winched into a rescue chopper sent from Townsville and treated at the Mackay Base Hospital for exposure.

About five hours later, CQ Rescue located the second man from Brisbane and he was able to alert police to the fact that there was a third person on the boat.  

He was found with no life jacket and no clothes on. 

Police said his account of events has not been entirely accurate due to suffering intense dehydration and hypothermia. 

Inspector Andrew Godbold said anyone on a fishing trip must make sure they take an EPIRB and personal flotation devices. 

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