By ANNE BESTON environment reporter
The whole of the Manukau Harbour is under a shellfish-gathering ban after a toxic algal bloom was discovered in water samples.
Eating shellfish from the harbour could lead to paralytic shellfish poisoning, said Auckland medical officer of public health Dr Donald Campbell.
People could become severely ill, even
permanently paralysed, from eating shellfish, which acted like a filtering mechanism of the highly toxic bloom.
It was the first time the invisible bloom had been found in the Manukau Harbour - it had been found before in the Hauraki Gulf.
"The bloom is a naturally occurring phenomenon but the whole Manukau Harbour is covered because we can't say it's localised in one area," Dr Campbell said.
Warning signs have been posted at Cornwallis Beach and Huia. The inner Manukau Harbour has a permanent shellfish-gathering ban.
Dr Campbell said swimming in the harbour was safe but some signs had been put up with a caution against swimming as well, because his office had run out of signs with shellfish warnings only.
The medical officer of public health tested the Manukau's waters every two weeks but the frequency would be stepped up while the ban was in place.
The ban would be lifted once water samples showed the algae had gone, Dr Campbell said.
As well as the warning signs, leaflets had been distributed to local marae warning against taking shellfish.
