A record number of new marine reserves are expected to be created this year.
Conservation Minister Nick Smith said recent evidence, which shows the reserves really work, highlights the need for more.
A report released on Wednesday by the Department of Conservation has shown marine reserves help improve the country's fish stock.
The Tonga Island marine reserve was established in the Abel Tasman National Park 20 years ago and there are now seven times the number of crayfish and 40 times the numbers of blue cod over 30cm in length, the review said.
In the Horoirangi Marine Reserve in Tasman Bay, crayfish are three-and-a-half times more abundant and blue cod are larger and more plentiful than they were when the reserve was created eight years ago.
Dr Smith said he intends to bring into force a new reserve in Akaroa in June and is hoping to create a first marine reserve for Otago. Five proposed reserves on the West Coast are well advanced through the process, and three very large marine reserves in the Sub-Antarctic islands are planned.
