Kaipara Harbour has been closed for recreational scallop fishing from this week.
Ministry of Primary Industries director of fisheries management, Stuart Anderson, said the closure has been put in place since Tuesday this week to help rebuild the scallop fishery for future generations.
Available scientific information, he said, showed scallop numbers in the harbour were at their lowest on record.
"Scallop abundance varies from year to year, however there appears to have been an overall decline in scallop abundance and distribution in the Kaipara Harbour over the last 60 years.
"Commercial scallop fishing in the harbour has been closed since 1986, and this new closure is a further step to help the scallop fishery to rebuild.