News Service from House Harris

NSW:Swimmers plunge into Harbour despite 3rd Sydney shark attack

SYDNEY, March 1 AAP - Hundreds of swimmers plunged into Sydney Harbour for the annual Swim Classic undeterred by news of a third shark attack in Sydney in as many weeks.

A 15-year-old boy suffered severe leg lacerations and is in a stable condition after being attacked by a shark at Avalon Beach in Sydney's north about 6.45am (AEDT) on Sunday.

The attack comes less than three weeks after a shark mauled a navy diver at Woolloomooloo Bay, in Sydney Harbour, and a surfer was attacked at Bondi a day later.

Sydney Harbour Swim Classic organisers said they were aware of the Avalon attack but decided to go ahead with the race because it did not occur in the harbour.

"If we'd spotted one in the harbour we'd have shut it down," event organiser Adama Wilson told AAP.

"That was our safety protocol."

About 900 swimmers took part in the races between the Sydney Opera House, Fort Denison and Farm Cove.

"In light of what happened at Avalon which is, I don't know, 50km away ... it's a consideration to have heard it and to understand that swimming at 6.30 in the morning, which they shouldn't have done again, but it wasn't going to affect it (the race)."

Competitor Tony Hogan, 43, said he heard about the Avalon attack before the Sunday swim but was not worried about competing.

"It's a safety in numbers type thing. Look, they patrol it pretty well, but there's a lot of safety attached to it, whether there's snorkellers or lifesavers on their boards or helicopters over the top," Mr Hogan told AAP.

"It wasn't really a concern for me. I just wanted to get through the race."

A dive photographer told AAP he saw no sign of sharks while photographing race competitors underwater.

Seconds before the starter's pistol fired, Carissa Lonwen, 30, said she was "not really worried" about another shark attack in the harbour.

"There was always the potential that something was going to happen," she said.

"It's not exactly swimming at shark feeding time so, hopefully, that doesn't impact on it.

"We're swimming in numbers, so hopefully you're not the one."

Veteran Sydney Harbour swimmer Ian Black, 45, and his friend Bernie Baer, 54, said news of shark attacks had not affected their decision to enter the harbour swim.

"I don't think the shark will make it down here in time," Mr Black joked.

"He'd be scared silly if he sees 800 swimmer coming at him."

The Avalon incident is the third serious shark attack in Sydney in less than three weeks and comes after repeated warnings by authorities for beachgoers not to enter the water at dawn or dusk due to increased shark activity.

Navy clearance diver Paul de Gelder was lucky to survive after being mauled by a 2.7-metre bull shark off Garden Island, in Sydney Harbour, on February 11, causing him to lose a hand and leg.

Just a day later, 33-year-old surfer Glenn Orgias was attacked by a 2.5m great white that shook him and nearly severed his left hand.