A man attacked by a four-metre shark while surfing on the NSW mid north coast is in a stable condition as his family appeals for support in the wake of his "life-changing" injuries.
Port Macquarie man Toby Begg, 44, suffered severe injuries to his legs when he was attacked by the shark, thought to be a great white, while surfing at Lighthouse Beach on Friday morning.
He was transported via helicopter to John Hunter Hospital in Newcastle for emergency surgery, and a hospital spokeswoman told AAP on Saturday he remains there in a serious but stable condition.
Mr Begg's brother-in-law Chris Lenihan has launched a GoFundMe page to raise money for the "extremely serious and life changing" injuries the surfer has suffered.
"It is very early stages and the full extent of his injuries are being uncovered however, he will require many surgeries and has years of rehabilitation ahead of him," Mr Lenihan wrote.
More than $10,000 had been raised by Saturday afternoon.
Mr Lenihan wrote that his brother-in-law, a skilled builder, had been lucky that an off-duty emergency doctor was on the beach at the time of the attack to help apply a tourniquet using leg ropes from surfboards.
Chief Inspector Martin Burke said on Friday Mr Begg had managed to fight off the predator.
"The reports are the man has tried to fight this shark for up to 30 seconds and has then swum himself to shore where he has realised he has sustained significant lower leg injuries," Insp Burke told radio station 2GB.
The Fire and Rescue NSW Port Macquarie station, of which Mr Begg was a former member, has also launched a fundraiser on its Facebook page.
Lighthouse Beach - a popular surf spot - is unpatrolled at this time of year, with regular surf lifesaving patrols due to start in a few weeks' time for the school holidays.
Port Macquarie Hastings Council has 15 smart drum lines along the region's coast, with two drones and a listening station also deployed to detect tagged sharks.
A number of great white sharks have been tagged and released in the area recently, including a 2.28-metre shark at nearby Shelly Beach on Tuesday and a 2.96-metre shark at North Shore Beach last Saturday.
The beach was closed for 24 hours following the attack, with a spokesman for the Australian lifeguard service confirming on Saturday it had reopened.