POLICE divers will today seek to enter the sunken vessel Dianne, where the bodies of six fishermen and best mates are feared to be entombed.
Families were briefed about the discovery of the missing boat yesterday afternoon at the tail end of the fourth day of searching.
The "slug boat", converted from a trawler for sea cucumber fishing, was found in about 30m of water, two to three nautical miles off Round Hill Headland and the Town of 1770.
Divers confirmed it was the missing boat. Water police guarded the site overnight, ahead of an expected grim day today when police divers will attempt to enter the boat to search for, and possibly retrieve, the men's bodies.
A full recovery operation would commence this morning, police said.
Throughout the ordeal, relatives have refused to give up hope of the men being found alive.
Torrid weather has hampered search efforts since the alarm was raised on Tuesday morning that the boat had gone down in rough seas the previous evening.
But yesterday conditions began to improve, allowing searchers to use sonar equipment to scan the seabed for the first time.
Seven police divers from Brisbane and two from NSW were sent into the search area yesterday on board the police vessel Conroy, one of two vessels using sonar throughout the day.
Police had been highly confident they would discover the sunken boat, based in part on descriptions from the sole known survivor, Ruben McDornan, and information from the vessel's tracking system. A rescue operation has transitioned to a recovery effort, with the divers focused on entering the sunken vessel to look for the men.
They can expect to encounter a tricky and dangerous environment.
The Dianne was fully laden with equipment and supplies that would have been tossed about inside.
On the day the vessel sank it had set off from Gladstone for a planned fortnight-long stint harvesting sea cucumbers, or beche-de-mer, around the Capricorn and Bunker group of islands and reefs, north of 1770.
The men on board were in their prime: seven larrikin mates who were living their dream on the water doing one of the most dangerous jobs on the planet.
Skipper Ben Leahy, 45, was joined by crew members Adam Hoffman, 30, Eli Tonks, 39, Adam Bidner, 33, Chris Sammut, 34, Zach Feeney, 28, and Mr McDornan, 32.
Survivor Mr McDornan owes his life to pure chance after forcing open a door enough to squeeze out of the upturned boat.
In a double miracle, he then survived a night drifting in rolling waves without a life jacket, before being rescued kilometres off shore by a passing catamaran that happened to sail within metres of him.
Commercial fishing, alongside trucking and agriculture, routinely sits atop lists of the most dangerous professions.
Numerous deaths are racked up every year, but Dianne's crew members were experienced, capable and had every reason to be confident in their ability to ride out the weather system lashing the Queensland coast with strong winds and flooding rain. They had decades of combined experience as divers, diving instructors and fishermen and had variously worked and played together for years.
The one shining light has been the incredible survival of Mr McDornan, who clung to the overturned and sinking boat for up to six hours before it was finally sucked to the ocean's floor.
In that time, he did not see any of his friends emerge. He then spent another six hours treading water before 38-foot catamaran On the Level appeared alongside him, saving his life.
There were no other vessels in sight, and he was only hours from death when he grabbed the life line thrown to him and hugged his rescuers.
He is back on land in Gladstone, where 30 relatives of the fishermen have gathered. "We got our boy back yesterday and he is doing OK considering everything that has happened," his wife Sammy wrote on Facebook yesterday.
"Our love, thoughts and hope are with our slugger families still without their boys, please keep them in your thoughts.
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