A MELBOURNE doctor has been identified as the 33-year-old who as killed in a fatal shark attack in the Whitsundays.

Daniel Christidis, who works as a urologist at Melbourne’s Austin Health, had been on a charter boat with friends on Monday when the attack happened, according to The Australian.

Police said he had gone paddle boarding and then swimming at Cid Harbour before he was bitten about 5.30pm.

Dr Christidis and a woman were taking turns on a paddle board, with the attack happening when he got off the board.

Queensland Police patrol inspector Steve O’Connell said the friends with Dr Christidis when the attack happened were “extremely distraght”.

“Every solid effort was made to save that man’s life,” he said.

Tourists have now been warned not to swim at the popular spot where he was mauled by a shark and died from his injuries.

Mr Christidis was flown to Mackay Hospital in a critical condition with bites to his left thigh, right calf and left wrist. The wrist injury was thought to be a defensive wound.

He later died in Mackay Base Hospital after suffering massive blood loss.

The tragic incident happened close to where two people were mauled by sharks in separate incidents in September.

An Austin Health spokeswoman says staff are being offered counselling after the “tragic loss”.

“We are deeply saddened by the tragic loss of Dr Daniel Christidis who was a research fellow with Austin Health. Our thoughts are with his family during this difficult time,” she told AAP in a statement.

Insp O’Connell describe the incident as a “horrible situation” for the people on holidays.

“Every effort was made to save that man’s life,” Mr O’Connell said, adding the friends were “extremely distraught” and “going through a hell of a time”.

“I’ve been in the Whitsunday area on and off for 30 years and apart from some minor nips and bites I’ve never heard of substantial attacks like what we’ve seen in these three attacks,” Mr O’Connell told media this morning.

“I believe the message we want to get across is don’t swim in Cid Harbour. At all.”

Police said they would not provide details on the condition of the man until they had spoken to his next of kin, who officers had not been able to locate.

After the attack the man was pulled aboard a nearby boat. He was treated by a paramedic from Hamilton Island, two off-duty doctors and an emergency department nurse from nearby boats before the arrival of the RACQ CQ Rescue helicopter.

Rescue crewman Ben McCauley described the man’s injuries as “absolutely horrific”, adding: “He’d suffered very serious bites, significant blood loss as well as cardiac arrest … ”

The critically ill man was resuscitated twice in less than 45 minutes, Mr McCauley said, before he could be transferred by tender back to shore and flown to hospital.

Mr McCauley said there were about 20 boats in Cid Harbour at the time.

He described the third shark attack he’d attended in less than two months as “just totally unbelievable” and “the worst one yet”.

The attack comes after a two tourists were mauled by sharks in the same area in September.

Authorities told 9 News the recent deadly attack was the “worst yet”.

Queensland Fisheries killed four tiger sharks in the area, including one up to 3.7 metres long, after the attacks on Tasmanian woman Justine Barwick, 46 and Melbourne schoolgirl Hannah Papps, 12.

Ms Barwick, a mother-of-two was bitten on her left thigh while snorkelling. The next day, Hannah, who was holidaying with her father and sister, received a life-threatening wound to her right leg while swimming in shallow water the harbour. Her injuries were so severe, her leg later had to be amputated.

Jonathan Clarke, of Sea Shepherd Australia told The Guardian in September that the area was known among Whitsundays locals as “no-go zone” for swimming and that drum lines designed to deter sharks were often left for days without bait, creating a “false sense of safety” for swimmers.

Just weeks ago, authorities and shark experts deployed shark control drumlines in response to the devastating attacks.

Drumlines involve a baited hook attached to a buoy and are placed strategically, usually near swimming areas, to reduce the possibility of further attacks by capturing sharks.

While shark experts say it’s difficult to identify what exactly caused the attacks, they have urged swimmers to take sensible precautions when entering areas of water in the Great Barrier Reef Marine Park, which covers an area of 344,000sq km and is home to about 88 species of sharks.

Queensland Shark Control Program manager Jeff Krause described the attacks as “unprecedented”.

“The priority is to reduce the current risk of dangerous sharks being in the immediate area,” Mr Krause said.

“While shark control equipment does not provide an impenetrable barrier between swimmers and sharks, it is effective in reducing the overall number of sharks in the area, making it a safer place to swim.”

Six tiger sharks were caught on the drumlines.

However, Whitsunday MP Jason Costigan last night called for drumlines to be permanently set in popular spots in the Whitsundays.

“We need drumlines and nets off our popular swimming beaches in the Whitsundays like most other populated centres up and down the Queensland coast,” he told the Courier Mail.

“It’s about time we had the same levels of protections as other places.”

Cid Harbour is a popular spot for boats to anchor when touring the Whitsunday Islands or the Great Barrier Reef.

The harbour has beaches and bush walking trails.