Environmentalists are slamming a lack of action at turning the dire state of the Hauraki Gulf around and are calling for 30 per cent of the Marine Park to be protected from fishing by 2030.
The ambitious target comes after another damning report into the state of the gulf, highlighting fisheries on the verge of collapse and sediment-choked and polluted waterways.
Authors warned few improvements have been made since the Hauraki Gulf Marine Park was established 20 years ago, with population growth, coastal developments and climate change all pointing towards an even more dire future without drastic action.
Environmental education group Blake programme manager and PhD student Jacob Anderson attended the launch of the report - the sixth since 2000 - and said it was quite a "depressing affair".
"It was another grim report, and we expected some kind of announcement - but there was none."
• State of the Hauraki Gulf: Crayfish in peril, snapper just hanging in there - report
• Island Hopping: Hot springs and stargazing in the Hauraki Gulf
• Mystery solved: MPI reveals probable source of thousands of dead fish around Hauraki Gulf
• Thousands of dead fish around Kawau Island in Hauraki Gulf off Auckland coast
Twenty-two per cent of all the gulf's seabirds were threatened, compared with 4 per cent 20 years ago.
Tāiko/black petrels were dying at unsustainable rates due to commercial fishing; kōura/crayfish were classed as functionally extinct, and popular fish species such as snapper and tarakihi remained at concerningly low levels.
Report authors also highlighted the march of the kina barren, due to a depletion of kina's key prey, crayfish and snapper.
Anderson and a group of likeminded environmentalists and scientists were calling for a new marine protection vision.
"We have a conservation goal on land with Predator Free 2050, which has really captured people's attention. But there is nothing in the marine space.
"Land-based conservation is an easier sell because it doesn't take something away from someone when you eradicate a possum or a rat.
"But by failing to restore marine ecosystems and protect marine species we've already stolen the chance for future generations to enjoy the splendours of the gulf.
"So we see 30 per cent by 2030 as a comparable goal. With the America's Cup next year we have a fantastic opportunity to lead by example locally in marine protection."
At present there were six marine reserves - covering 0.3 per cent of the gulf - where no habitat disturbance or removal of marine life was allowed, and five MPAs where no bottom-contact fishing was allowed.
The area of marine reserves had increased only 0.05 per cent since park was established in 2000.
The Hauraki Gulf Forum, set up alongside the park to advocate for its protection, wants to see 20 per cent of the Marine Park come under some form of protection, including at least 10 per cent as no-take marine reserves.
It also wants to restore and establish 1000sq km of shellfish-beds and reefs.
Globally, scientists have been calling for 30 per cent of the ocean by 2030 – a target scientists say is crucial in order to safeguard wildlife and to help mitigate the impacts of climate change.
Nationally just 0.4 per cent of New Zealand's marine and coastal area is covered no-take marine reserves, well shy of the country's international commitment set in 2011 to have 10 per cent fully protected.
"We have no roadmap, and so far, there hasn't been anyone brave enough to take it on," Anderson said.
New networks of marine protection would not be limited to no-take areas, and could include dynamic and long-term rāhui depending on seasons and recovery rates, along initiatives like ahu moana that allow mana whenua and local communities to work together to manage their coastal area using existing statutory rights and practices.
"Regardless of commercial and recreational rules and rural and urban runoff, the health of the Gulf is trending downwards and the idea of fishing being a birth right, or business as usual attitudes must change," Anderson said.
"It would boost tourism, create new jobs, improve fish populations, restore kelp forests and seagrass meadows which also help sequester carbon, and improve water quality through restored shellfish beds which as filter feeders act as cleaning agents.
"The reality is we know currently it is not working."
Minister of Conservation Eugenie Sage said she agreed drastic action was needed.
"The gulf has been over-exploited, ecosystems are collapsing, we need to do more."
She also agreed the amount and size of protected areas needed to be drastically expanded, and this was a focus of the Sea Change Plan ministerial advisory committee, established last year to rekindle the much-touted cross-sector approach to restoring the gulf's health.
Despite minimal action over the past 20 years, Sage said the next 20 would be much different.
"These reports now have so much detail in them it is really clear what the issues are and that action needs to be taken.
"While it has been contentious in the past, there is much more recognition now, from all sectors. Look on land, Auckland Council is taking actions to improve water quality and reduce sediment, and so in the water we need to look to do more."
Any resolutions and protection options needed to be decided with support of the gulf's mana whenua, which was where customary protections such as ahu moana and rāhui were important, she said.
The advisory group would be reporting mid-year recommendations around increasing marine reserves and other forms of protected areas in the gulf, she said.
Industry body Seafood New Zealand did not address specific questions about increasing no-take marine reserves, but chief executive Tim Pankhurst called for the entire park to "protected".
"That means understanding the risks and pressures posed by human activities and addressing those appropriately while allowing for social, cultural and economic use of our natural resources."