Most commercial fishing will be restricted in two new marine parks to be announced by the government this afternoon.
The separate proposed parks will cover the inner Hauraki Gulf, and the Marlborough Sounds at the top of the South Island.
Recreational fishing will still be permitted, but the government will be forced to pay compensation to commercial operations holding fishing quotas in the areas involved.
The fish species most affected by the proposed changes will be snapper in the Hauraki Gulf, and cod in the Marlborough Sounds.
Previous studies of both areas have indicated fish stocks were depleted, and in danger of collapse.