Fish and birdlife in the Hauraki Gulf are under increasing threat from commercial fishing and pollution.
Auckland Mayor Phil Goff is pledging to prioritise better care of the gulf this year, which he says starts with extending the size of the marine reserve.
Hauturu - Little Barrier Island - is one of the most protected in the country.
"Little Barrier is the poster child of conservation in New Zealand," Associate Professor in marine science Nick Shears says.
But the water surrounding it is a different story.
"It really highlights a mismatch between what we can do on the land and how we protect the land, we can see what's happening on the land, whereas, in the marine environment, we really see it only as a source of food."
The Hauraki Gulf is beautiful until you dive a bit deeper.
On Tuesday, a group of marine and conservation experts, along with officials, gathered to discuss the destruction being caused by overfishing and pollution.
On a scale of 1-10, they were each asked to rate the state of the Hauraki Gulf.
"Midway," the Department of Conservation says.
"We're sitting at four and we're declining very rapidly," Ngati Manuhiri chairperson Mook Hohneck says.
"Probably only a four," Auckland Mayor Phil Goff says.
"It's probably a 3.5 on my scale," marine biologist Dr Tim Haggart says.
They're sad numbers that are based on 20 years of number gathering.
"Crayfish or snapper, they're at about one or two out of 10, their stocks are around 10 to 20 percent of what they were historically," Shears says.
DoC rangers Dr Leigh Joyce has watched as the ocean changed around her in the 10 years they've lived on the island.
"Less fish, more kina barrens, even in a place like this that you think is pristine, we are a nature reserve but our oceans are still being affected," Joyce says.
Only 0.3 percent of the Hauraki Gulf is a marine reserve, and there is a resounding call for the size of that protected area to be extended as soon as possible, and especially around this island.
"When you see the non-existence of different species of fish and of marine life that's happening, it's very simple to say it's not sustainable, we're taking too much out of the sea," Hohneck says.
The gulf is in trouble out here, but it's on the doorsteps of Aucklanders now too - over New Year's 50 beaches were deemed unswimmable due to wastewater pollution.
"That's why literally we're investing hundreds of millions of dollars to clean up the water quality for our city," Goff says.
The damage across the gulf is already widely considered irreversible, but Hohneck has a desperate plea: "We need to stop it now."
To ensure 'clean green' New Zealand applies to the deep blue too.
