Nick Smith was criticised by the fishing industry when the Government announced the Kermadec Ocean Sanctuary last month but says the decision will not harm and could even help New Zealand's seafood sector.
The Environment Minister and Nelson MP said there was an irony in the fact that as the minister responsible for setting up the no-fishing, no-mining sanctuary covering an area twice the size of New Zealand's land mass, the people upset the most were in his own constituency, which contains the biggest fishing port in Australasia.
"There will be some political cost, but I accept that. I'm in Parliament because I actually want to do some stuff that I think is good for New Zealand," he said.
He had noted a remarkable change in attitude by the fishing industry over the past 25 years and believed that its commitment to sustainable fishing and conservation of marine wildlife such as whales and seabirds was genuine, not just designed to win over the public.
"I don't see the objective of New Zealand being a world leader in good oceans management as in contrast with the fishing industry. I actually think it is very much part of the same story."
Smith said the quota management system applied to commercial fishing was one of the best in the world, and New Zealand had a good record of engaging with communities on marine conservation and management.
"I'm really excited about the combined future of the change in attitudes of the fishing industry and the real opportunity for New Zealand to be a global leader and to get a premium for its fisheries products."
Among his critics over the Kermadec sanctuary was Nelson tuna fishing pioneer Charles Hufflett, who said it would strangle the opportunity to catch migratory tuna there and was largely driven by the wealthy US-based Pew Foundation, which has successfully advocated for other such reserves around the globe.
But Smith said he'd had more meetings and discussions with Hufflett than with Pew. He'd also been lobbied by WWF New Zealand and Forest and Bird, receiving "thousands of cards" favouring the sanctuary.
"I reject that Pew has somehow been in private closed talks with the Government and it has been them that has somehow with their rich resources persuaded the Government."
Instead the Government saw the merits of the argument and "the big global picture that we need to understand".
In the 20th century there had been huge debates about land use - what should be national park, what should be used for farming and development.
"There is going to be an equally big argument this century around what portion of the oceans we use to fish, what areas we use to mine ... we're saying we're a developed country, we are a country that has the fourth largest [Exclusive Economic Zone] in the world, we brand our fish products as coming from one of the most sustainably managed fisheries in the world, we think it is responsible to set aside a portion of our EEZ and our coastal environment for nature's purpose."
The Kermadec sanctuary, which the Government intends to have in place within 12 months, will be the largest no-take reserve in the world. That's because, unlike similar large sanctuaries being set up by other countries, there is no requirement for customary fishing. The only residents of the Kermadecs, a near-pristine island chain 800-1000 kilometres northeast of New Zealand, are Kiwi scientists.
The sanctuary will take the proportion of New Zealand's EEZ under full marine protection from 0.4 to 15 per cent.
There are 44 marine reserves making up 10 per cent of New Zealand's territorial sea, extending 12 nautical miles (22 kilometres) from the coastline compared with the 200 nautical miles (370km) in the EEZ.
But Smith said he would not want the Kermadec move to send a message that the Government has done enough to protect marine environments. It was ambitious to do better, he said.
"There's only a few areas of endeavour where New Zealand is truly a global player - rugby, the dairying industry, and oceans, which tends to be understated. We don't have a bad record but we do think there are areas where we need to lift our game."
The Government has already stated its intention of creating large recreational-fishing only zones in the Hauraki Gulf and Marlborough Sounds, squeezing out a commercial sector that has fished both areas for generations.
He said the 1971 Marine Reserves Act was a world leader in its day, but was now "a long way off" international best practice.
He is promoting new legislation that will provide not only for total no-take but also "recreational fishing parks", reserves specially to protect the seabed from trawling and mining, and a new category of species-specific sanctuaries to protect seabirds and ocean dwellers such as great white sharks.
"We want to provide a broader range of marine protected areas and we want to change the way that they're created. We want to be getting in with the fishing industry, environmentalists and iwi, working together," Smith said.
He will be issuing a discussion paper on that, and is aiming to have the legislation in place for the two recreational fishing parks during the current Parliamentary term, which ends in 2017.
As for the industry complaints about the Kermadecs, Smith said the Government's hand was forced by a seabed mining application, but that he would be consulting both the seafood sector and iwi on the detail of the legislation.
He said he didn't deny the removal of the opportunity to catch fish there in future.
But it was really difficult to create no-take areas where fishing was well-established.
"The big gains of creating these large ocean sanctuaries is not so much that they make a massive difference on day one, because actually there's not that much fishing activity.
"It's rather the setting aside of that area over the next 30 years that won't allow any development that would have occurred."
There is also an obvious eco-tourism potential, but Smith said that wasn't the motivation.
"The Government is doing it for nature conservation reasons. We think there are parts of the global ocean that should be set aside where humankind should say 'no, we're not going to touch those'."