Shark bites surfer in leg at Western Australia beach

Police are investigating the attack.

A man attacked by a shark in Western Australia's south managed to body-surf back to shore before friends used rope from his board as a tourniquet.

The man, in his 30's, was bitten on the leg at Lefthanders surf break in Gracetown about 8am local time.

Friends used the rope from the victim's board as a tourniquet and gave him first aid until emergency crews arrived from Margaret River within six minutes, a St John Ambulance spokesman told AAP. The victim was conscious when he was flown to Royal Perth Hospital.

Surf photographer Peter Jovic saw the attack from the beach and said there were only about five people in the water at the time.

"If anyone is familiar with the Mick Fanning moment at Jeffreys Bay a couple of years ago, it was very similar to that, where a shark pretty much popped up and ended up knocking a surfer off his board," Jovic told ABC radio.

"There was a lot more thrashing around after that, it was pretty hard to see what was going on.

"The surfer who was being attacked ended up miraculously body-surfing into a little wave and getting pushed in by a local at the same time, who was out there with him, and making it to shore before everyone came to his aid."

Jovic said everyone was "walking around like stunned mullets" after the attack.

AAP understands the man has lived in Gracetown for some time, with one friend describing him as "an awesome guy".

Surf Life Saving WA said a 4m shark and whale carcass were spotted at 10am at Lefthanders.

Beach closures are in place for the Gracetown area, including North Point, Big Rock and Lefthanders.

Police are investigating a possible shark attack In Western Australia.

The Margaret River Pro international surfing competition, which is about 15km away from the attack, was suspended for about one hour, but then resumed at Main Break.

"Surfer and staff safety are top priorities for the World Surf League," a spokeswoman said. "Further enhanced safety measures, including ski and drone presence, will be added to the event's mitigation protocols."

Chris Boyd, 35, was killed by a shark in 2013 at Umbies surf break in Gracetown. Nick Edwards, 31, also died after a shark attack while surfing at nearby South Point in 2010.

- AAP