Marine biotoxin alerts.

Shellfish and seawater samples around New Zealand are tested each week to ensure they are not contaminated with biotoxin from blooms of algae. Public warnings are issued when shellfish are not safe to eat. This page contains information relating to the non-commercial (recreational and traditional) taking of shellfish only.

This page is updated as soon as new information comes to hand. All the warnings on this page are current and remain in force.

Marine biotoxin warnings currently in force

North Island

Toxic shellfish warning extended along coastline 19 December 2014

Following ongoing shellfish toxin monitoring the Paralytic Shellfish Poisoning (PSP) warning has been extended.

The affected area now includes the entire coastline from Whakatane Heads in the Eastern Bay of Plenty, all the way along the coast to Waihi Beach, and up the eastern side of the Coromandel Peninsula to the river at the southern end of Whangamata beach.  All harbours, estuaries and islands along this coastline are included in the warning.

“Ongoing monitoring has shown high levels of paralytic shellfish poison present in shellfish along this coastline.  Shellfish in the affected area should not be taken or eaten,” says Medical Officer of Health, Dr Phil Shoemack.

The health warning applies to all bi-valve shellfish including mussels, pipi, tuatua, cockles, oysters, scallops as well as cat’s eyes, snails and kina (sea urchin).    PSP is caused by natural toxins that are produced by algal blooms and accumulate in shellfish that feed on the algae. Shellfish containing toxic levels of paralytic shellfish poison don't look or taste any different from shellfish that are safe to eat. Cooking or freezing the shellfish does not remove the toxin.  Paua, crayfish and crabs can still be taken but as always, the gut should be removed before cooking or eating.

In the last two weeks, 12 people have been reported to Toi Te Ora – Public Health Service with paralytic shellfish poisoning.  Eating shellfish affected by paralytic shellfish toxin can cause numbness and tingling around the mouth, face, hands and feet; difficulty swallowing or breathing; dizziness; double vision; and in severe cases, paralysis and respiratory failure.  These symptoms can start as soon as 1-2 hours after eating toxic shellfish and usually within 12 hours.  Anyone suffering illness after eating shellfish should seek urgent medical attention.

Monitoring of toxin levels will continue along the coast and any changes in advice will be communicated accordingly.  The public can obtain up-to-date information on the toxic shellfish health warning through these channels:


South Island

Shellfish Closure Onapua/Opua Bays, Queen Charlotte Sound- 17 December 2014

Today the Medical Officer of Health has warned the public not to take or eat shellfish from the Onapua/Opua Bays in Tory Channel. 

Nelson Marlborough Medical Officer of Health, Dr Ed Kiddle said, “Routine testing of shellfish in this area has shown higher than acceptable levels of Saxitoxin to be present.”

Saxitoxin is a compound belonging to the Paralytic Shellfish Poisoning (PSP) group.

Dr Kiddle said symptoms of PSP poisoning were numbness and tingling around the mouth, face or extremities; difficulty swallowing or breathing; dizziness; double vision. In severe cases, paralysis and respiratory failure can occur.

“Acute symptoms usually occur within 12 hours of consuming shellfish,” said Dr Kiddle.  He advised people not to eat kina, mussels, pipi, tuatua, oysters and cockles harvested from the affected areas since December 10, 2014.

Any shellfish that has been harvested since December 10, but not yet eaten, should not be consumed. Freezing the shellfish does not kill or remove the toxin,” said Dr Kiddle.

He said this is the same toxin that closed the Queen Charlotte Sound and Tory Channel areas in February of this year. 

“Although routine sampling in Queen Charlotte Sound and Tory Channel has shown no toxin yet present, previous experience tells us that the toxin may show itself in the weeks following the closure of Onapua/Opua Bays in Tory Channel.

“Therefore, continued monitoring of these areas may also result in further closures.”

Scallops, paua, crab, and crayfish may still be eaten if the gut (and skirt of scallops) is completely removed prior to cooking. If the gut was not removed its contents could contaminate the meat during the cooking process.

“Cooking affected shellfish does not remove the toxin,” he said.  Fish, such as snapper, cod, gurnard, and terakihi were not affected by the toxic algae and are still safe to eat, if the gut is removed,” he said.

The affected area (shown on the attached map) is all of inner Onapua/Opua Bays of Tory Channel of a line drawn across Katoa Point. 

“Continued monitoring of the situation is planned, but in the meantime people should not take shellfish from this area,” said Dr Kiddle.

People who want more information about the safety of shellfish in their possession should contact the On Call Health Protection Officer on Blenheim (03) 520 9999 or Nelson (03) 546 1800. People who become ill after eating shellfish should seek medical attention.

Toxic Shellfish Areas


This Area Is Affected By Shellfish Biotoxins.

  • This Area Is Affected By Shellfish Biotoxins.
  • Shellfish Consumed From This Area May Be Harmful To Health.
  • Crayfish, Crab, Paua and Finfish may be consumed if the gut is removed.
  • Only the white muscle of Scallops may be consumed

Nelson Marlborough Public Health Service
Blenheim (03) 520 9914 or Nelson (03) 546 1537 (During Work Hours)

After Hours – Contact The On-Call Health Protection Officer: Blenheim (03) 520 9999 Or Nelson (03) 546 1800

Public health unit contacts