The man was flown in a Westpac rescue helicopter to John Hunter Hospital in a critical condition.
The man is now in a stable condition, a hospital spokesperson confirmed.
The tourists, visiting from Switzerland, were filming dolphins with a GoPro while they were swimming at the beach, possibly inadvertently recording the horror shark attack at the same time.
Police will now review the footage to determine which shark was responsible for the mauling.
Experts believe it was a mature bull shark.
Kylies Beach is a secluded spot in Crowdy Bay near a popular camping spot, which is not patrolled by lifeguards.
Authorities believe a bull shark attacked the Swiss couple while they were swimming. Photo / Getty Images
The tourists arrived at the campsite Wednesday and were believed to be travelling in a vehicle hired from Queensland.
Beaches have since been closed until further notice.
NSW Ambulance Superintendent Josh Smyth described the incident as “tragic”.
He thanked the witnesses who jumped in to render first aid to the couple.
“I need to [give] a shout out to the bystander on the beach who put a makeshift tourniquet on the male’s leg [which] potentially saved his life and allowed NSW Ambulance paramedics to get to him and render the first aid,” he told reporters.
“The courage from some bystanders is amazing in the situation and … to put yourself out there is very heroic.
“The community … rely on those things.”
Speaking to NewsWire, a MidCoast Council spokesperson said the council was working alongside National Parks and Wildlife staff and Emergency Services during the investigation.
“MidCoast Council’s Mayor Claire Pontin has expressed her sadness at the loss of life and extended her condolences to the families involved,” they said.
The Consulate General of Switzerland in Sydney told news.com.au: “We can confirm that two Swiss nationals were involved in a shark attack in Australia. One Swiss national lost her life, and another Swiss national was injured.
“We are in contact with the local authorities and are supporting the relatives within the framework of consular protection.”
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