Commercial fishers who have worked in the Hauraki Gulf for generations are bracing for a fight with the Government.
They say proposals to preserve the inner gulf for recreational fishers will put them out of business overnight, causing job losses and possibly a spike in the price of fresh fish.
Sport fishing groups are not completely sold on proposals either, saying that the effect on fish abundance will be minimal.
But the Government warns fish stocks need to be protected.
Unveiled as a National Party election promise in 2014, the recreational fishing parks in the Hauraki Gulf and the Marlborough Sounds are now in the consultation phase.
The Hauraki Gulf fishing park covers from Leigh, 80km north of central Auckland, to the north-western tip of the Coromandel Peninsula, and takes in popular fishing spots around Kawau Island and Waiheke Island. It also captures commercial fishing grounds.
Peter Thorburn, who runs Piako Petes, has caught flounder in the mudflats between Thames and Miranda for 20 years.
"My family has been fishing here since before the Treaty," he said. "I'm 59 years old and don't want to go and start up anywhere else. I will go down kicking and screaming."
A commercial fishing ban would have a massive flow-on effect, he said. "From truck drivers to factory hands to restaurants and cafes. And if you don't have this Hauraki Gulf-caught fish for the Auckland market, do you realise what will happen to the price of fish?"
Thorburn was sceptical about potential compensation. When his $3000 annual kahawai quota was halved because of a Treaty settlement in 2004, he was compensated $58.25.
He still has the cheque, too angry to cash it.
Janene Wolfe, who co-owns Thames Wholesale Fisheries, said she would have to lay off some of her 15 staff if commercial fishing was banned from the inner gulf.
"We would adapt, but it would have an impact on us and the community."
Environment Minister Nick Smith said it was inevitable that the proposed parks would have a "tough impact" on fishers.
"But the Government thinks that the overall public interest is in creating these parks."
Auckland's growing population, rising boating numbers, and fish-finder technology were putting pressure on fish population numbers.
The Government believed that fish species in the inner Gulf had greater value to the recreational sector than the commercial sector.
Smith said "tens of millions" would be paid in compensation to fishing companies, though they will have to show they have been significantly affected by the fishing ban.
The Ministry for the Environment estimates that 80 commercial vessels catch 870 tonnes a year within the proposed Hauraki Gulf park, including 260 tonnes of snapper.
Figures on recreational take are not available, but the ministry says up to 21,000 people fish in the Gulf on a summer day.
Richard Baker, a spokesman for influential lobby group LegaSea, says the initiative would help preserve the ocean floor from trawling. But he did not believe the parks would help fish stocks grow.