The sons of Stephen Asplet and Lee Casaceli were both injured in stingray attacks in Gunnamatta beach in October 2009 and December 2008 respectively.

Both parents are angry that protection nets were compromised, but a Sutherland Shire Council spokesman said the shark nets were State Government hardware, not designed to stop stingrays.

"These nets provide some protection for swimmers against large fish and sharks, but do not and cannot protect against stingrays, which naturally swim in the sandy or muddy bottom in very shallow water underneath these nets,'' he said.

"Stingray stings often occur as a result of people unknowingly stepping on a stingray while walking along the water's edge or while wading through shallow water.''

Sylvania boy Joshua Asplet, 14, was stung by a stingray on October 23.

His father said Joshua had been walking in shallow water in a section of Gunnamatta Park which is protected by shark nets.

"He said he felt a bad vibration and then a big bang into his leg.

"There was blood everywhere, I thought it had hit an artery.''

Mr Asplet said his family visit the park about 20 times a year without trouble from the venomous fish.

He believed shark nets should have kept stingrays away from the shore.

"I think if they have got them there people have got to feel protected,'' he said.

"[But] I know accidents do happen and things are going to slip in.''

Caringbah resident Lee Casaceli said her son Chris was 12 when attacked by a stingray at Gunnamatta Bay last December.

"It was terrible. He was in the shallows of the water. He was playing with some friends, playing on all fours,'' she said.

"The bleeding just went on and on.''

Mrs Casaceli said that polarised sunglasses can help swimmers see stingrays, and that scuffing while walking gives them a chance to escape from underfoot.

"If you slide instead of walk in shallow water it's much better,'' she said. "If you touch a stingray in the side it will run away.''

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