Mangawhai is the most important of the four sites, with half of the population's breeding pairs feeding on small fish found in the mangroves that grow in the harbour. These small, gull-like birds are already on the knife's edge of extinction, and yet we're at risk of losing this critical feeding ground.
Why? For the blind pursuit of a picture-postcard seaside. The Mangawhai Harbour Restoration Society (MHRS) is seeking permission to rip out the mangroves and "restore" the harbour to the free-flowing waterway of the 1950s, when roaming livestock had eaten away all the mangrove trees.
It wants to dredge the harbour and "restore the harbour to its original pristine state".
For Forest & Bird, it's a clear-cut issue. Surely we shouldn't risk species extinction for the sake of having easier boating access and muddy views?
The Northland Regional Council had the good sense to deny MHRS's 2011 application to remove all mangroves from the harbour.
The MHRS then tried through the Environment Court with a proposal to clear 60 per cent of the mangroves.
The Court recently announced an interim decision that permitted some mangrove clearance, probably around 14ha, with parties still to discuss the conditions for this to proceed.
It's a heavily reduced plan from the original 87ha the MHRS wanted removed. But did I mention fairy terns are internationally threatened and critically endangered?
We don't yet know whether the loss of these mangrove areas will directly reduce numbers of fairy tern chicks. What we do know is we can't afford to take the risk.
It's some topsy-turvy world where the community's decision-maker was being forced to weigh up the possibility of bringing a species to extinction against people wanting to moor their boats closer to their homes.
Forest & Bird isn't against development. But in this case, there's already so little safe coastline left for these birds. We're working closely with DoC and iwi to establish new breeding sites. Once we've got an established population of fairy terns elsewhere, then yes, we might look at digging up some of their Mangawhai feeding grounds. But that solution is a long way off.
All this fuss is not just for fairy terns. Mangawhai Harbour is also an important feeding site for endangered New Zealand dotterels. Other species - banded rails, grey ducks, South Island pied oystercatchers, Caspian terns, pied shags, black-billed gulls, fernbirds, bitterns and godwits - likewise visit and use the harbour and its shores.
It's disturbing that some people feel that nature has got it wrong. The Mangawhai mangroves are growing there naturally because of the mud being brought down by the rivers flowing into the harbour. Fish have found a natural home among the mangroves, and the fairy terns have found a natural feeding ground. The natural order of the harbour is not subservient to improving local amenity values.
Mother Nature is more and more frequently having to plead her case to exist. And plead it well, in a way that completely invalidates the threat. In this case, failure to do so would've given way to wanton development for improved seaside views and more space for jet skis and speed boats.
I am saddened that the development-at-any-cost mentality we've unleashed over the past two centuries is thriving in New Zealand. Still, when a group of people want to improve their real estate values at the expense of the world's rarest shorebird, I would hope our planning system might engender a little bit of precaution. I would hope Mother Nature wasn't so easily overridden.
I would hope common sense would prevail.
Dr Mark Bellingham is North Island conservation manager for Forest & Bird.
