A teenage surfer has described how he cycled home to his parents after he was attacked by a shark near Mandurah

Cameron Pearman was sitting on his board off Port Bouvard, south of Mandurah, around 6.15am on Saturday when the shark struck.

He told Fairfax Media he saw the shark just before it attacked.

"I saw the shark half a second before it bit my leg. It was fully grey all over. I didn't really feel anything at the time. It was a bit crazy for a moment but it started to hurt after the adrenalin wore off," he said.

The 13-year-old paddled to shore on Pyramids Beach as quickly as he could. 

"When I got there I pulled up the leg of my wetties and there was blood and cuts and I realised that I was so lucky I didn't lose my foot or something," he said.

The injuries sustained by Cameron Pearman when he was bitten by a shark at Port Bouvard on Saturday morning.

The 13-year-old had been surfing with his cousin who is a trained surf lifesaver. He carried out first aid before Cameron climbed onto his bike and cycled home.

"Dad didn't believe me for a bit but I showed him the cuts and then he believed me. Mum was a bit crazy," he said.

"I had something to eat then went to hospital to get the cuts cleaned and patched up."

The injuries were not serious but the shark that bit him had a mouth big enough to leave wounds on Cameron's right leg from the knee to the ankle.

But the encounter hasn't put the teenager off surfing.

"I'm hoping to get a surf in tomorrow," he said.

By then shire rangers are likely to have reopened the beach.

- WA Today