"The man and woman who was onboard have gone into the water in the late afternoon and they were taking turns at using a stand-up paddleboard", O'Connell said.
Daniel Christidis, 33, a urologist who was with a group of fellow medics, was fatally savaged by a shark in Cid Harbour in the Whitsunday Islands off the coast of Queensland where there has been a spate of recent attacks.
The victim was taken by helicopter to the Mackay Base Hospital, 100km to the south, where he died.
Shark control equipment had been temporarily placed in Cid Harbour following the first two attacks but was removed on September 27 after the potentially unsafe sharks were removed.
A man has died after he was attacked by a shark while swimming in Cid Harbour at the Whitsunday Islands, where two tourists were mauled a few months ago. A 12-year-old tourist, Hannah Papps, was attacked in the same harbor while swimming from a yacht the next day, losing a leg.
"We need to now have the scientific background and investigation of what is causing this sudden spike of attacks and interactions with sharks".
Following those attacks, local authorities conducted a culling of sharks in the area, capturing and killing at least four, including a 3.7 metre tiger shark.
"I feel devastated for the family and friends of this young man, I know that he would have received the best of care available from the Queensland Health Service, including RACQ CQ Rescue helicopter crew and my heart goes out to all involved", Craig Barwick said in a statement.
"The Cid Harbour area is not covered by the Queensland Government's Shark Control Program, which operates at 85 of Queensland's most popular beaches", he said.
Conservationists argue that drum lines kill sharks unethically, and also harm other marine life.