Fixing the Gulf
Auckland’s Hauraki Gulf is rightly considered one of the best reasons to live in and around the country’s most populated region. But some argue it’s a festering sore.
A recent opinion piece in the NZ Herald, jointly written by members of the Neureuter family, owners and self-proclaimed guardians of the Noises Islands in the Hauraki Gulf, got me thinking.
The Neureuter family has owned the Noises Islands for 85 years; the current generation can draw on memories that span 45 years. They obviously love the Hauraki Gulf and take their stewardship very seriously. But the family is concerned, having witnessed a steady decline in the health of the marine environment in the waters surrounding their islands.
In the article the family reports a marked decline in the abundance and diversity of marine life, particularly fish and shellfish. Crayfish have declined to the extent they are virtually absent around the Noises, the family says, compared to an abundance 40 years ago, and water quality has also become worse.
Increased sedimentation, evidenced by reduced water clarity, as well as increased nutrient levels, are affecting the relative abundance of marine plants and animals, some of which are disappearing altogether while others, often less desirable, are taking advantage of the changing living conditions.
A SHIFTING BASELINE
One of the difficulties we face when dealing with slow change is the phenomenon of the shifting baseline. Humans tend to live in the present. Each of us considers what we see and experience around us right now as ‘normal’.
We base our perception of normal on personal experience and observation, which usually spans just a few years. This is true whether we’re considering the current political situation, the climate/weather, or the state of the Hauraki Gulf’s fisheries.
It is hard to judge, for instance, whether the fishing we remember enjoying 20 years ago was better or worse than it is today. Lacking any empirical data, we have to rely on our memory and memory can be selective. Most of us see things through rose-coloured glasses and harbour fond memories of the ‘way we were’.
Fortunately, there is plenty of empirical data available around the environmental health of the Hauraki Gulf, thanks to the work of generations of scientists from many disciplines. Sadly, most of it supports the Neureuter family’s observations: the environmental health of the Hauraki Gulf is in decline and has been for as long as scientific records have been kept. Even worse, the rate of decline is accelerating.
But as the Neureuters point out, “Without educating Kiwis and new immigrants alike, how can they know that the Gulf they see today doesn’t represent a healthy functioning system and is in decline? Yet unmonitored plunder will turn the Hauraki Gulf into an environmentally-depleted area which will resemble the very places which many have sought to leave.”
CHALLENGES TO THE GULF
For many of us, myself included, the main concern has been the argument over who is going to be allowed to catch snapper in the Hauraki Gulf. This remains an important unresolved question, but as the Neureuters pointed out in their Herald article, it deflects attention from deeper environmental concerns.
These include sedimentation, agricultural and industrial run-off, shrinking species diversity, a fast-growing population, and a need to increase abundance across the whole marine ecosystem as well as improve overall monitoring.
Population pressure is perhaps at the root of all the environmental challenges faced by the waters of the Hauraki Gulf (and elsewhere around New Zealand). The beauty of the Hauraki Gulf makes the Auckland region a highly desirable place to live: Auckland is growing fast and the pace of growth is accelerating.
Since the early days of Maori settlement, land use changes have impacted on the waters of the Gulf. Forest clearance, intensive farming and horticulture resulted in increased sediment and nutrient loads in our waterways.
Explosive urban growth is seeing more and more greenfields developments resulting in accelerated silt run-off during the earthmoving and construction phases and permanent changes to the permeable surface when completed. Urban areas produce vastly more run-off than undeveloped land, unfiltered by natural wetlands, forest or even pasture. All the run-off eventually finds its way to the sea.
Sedimentation is one of the biggest threats to health of the Hauraki Gulf. Our expanding mangrove forests, not just restricted to the fringes of the Hauraki Gulf but evident in most northern harbours, are testament to increased sedimentation. Mangroves don’t take root in clean sand. They love mud and trap sediment in the margins where it eventually become solid land. Where mangroves grow there is plenty of sediment in the water.
High sediment loads stifle filter feeders and smother bottom dwelling plants and animals, completely altering sea floor animal and plant communities. Many parts of the Gulf now have shifting mud bottoms inhabited by a very narrow range of organisms. Species diversity is the big loser and the knock-on effect on the fish we like to catch is huge.
The next biggest challenge to the Gulf’s health are the nutrients transported to the sea by rivers and streams whose catchments include built-up areas and farmland. Intensive dairy farming with larger herds kept on smaller blocks and heavy fertiliser use have greatly increased the volume of nitrates and phosphates, among other nutrients, that find their way into the Gulf.
The Waikato is the most intensely-farmed region in the country and the volume of faecal matter and urine produced by the Waikato’s dairy herds is mind-boggling. A good proportion of it ends up in the Gulf.
A thousand years ago when the Hauraki Gulf was surrounded by virgin forest nutrient loads entering the sea were very low. But 150 years of land clearance, farming and urbanisation, topped off by the recent adoption of pasture irrigation to increase dairy yields, mean nutrient loads in our waterways have never been higher.
Next on the threat list is pollutants: these include industrial pollutants from factories, heavy metal and petro-chemical (fuel and rubber) run-off from our roads, as well as household waste and sewage. Auckland’s antiquated sewage system is overwhelmed every time it rains, dumping raw sewage into the harbour via stormwater drains to add to the untreated animal waste already deposited in the water by rivers and streams.
Then there is fisheries management. Presently management focuses on who may take what from where rather than on the health of the ecosystem as a whole. Damaging and highly extractive fishing still goes on, and with Auckland’s growing population and increasing proportion of new immigrants, some of whom are unaware of recreational fishing regulations or unfamiliar with accepted fishing practices, recreational fishing pressure could easily result in further resource depletion.
Even the proposed Hauraki Gulf Fishing Park, while it may provide better fishing for recreational anglers inside its borders, does nothing to address the ongoing depletion of fish stocks or enhance biodiversity.
THE WAY FORWARD
Clearly halting the Hauraki Gulf’s environmental slide won’t be easy; reversing the decline and making things better will probably be harder still… But not impossible, according to the Neureuters.
The Hauraki Gulf Forum was established in 2000 as part of The Hauraki Gulf Marine Park Act. Regular State of the Environment reports issued by the forum describe the declining health of the Gulf. In response to recommendations made by the forum the group Sea Change was established, led by a stakeholder working group with diverse interests, backgrounds and opinions.
Sea Change seeks collaborative solutions to the major issues affecting the Gulf. It has the backing of Auckland Council, Waikato Council, Department of Conservation, Ministry of Primary Industries and tangata whenua.
Members of the working group have developed mutual respect and the ability to work together so they can recommend positive changes – they are well aware of the challenges facing the Gulf, among them the need to eliminate or reduce damaging fishing and extractive practices.
Sea Change advocates better education and better control of what pours into the Gulf, as well as the establishment of a network of marine protected areas around the Gulf. It doesn’t support the proposed Fishing Park, claiming it offers no solutions to any of the Gulf’s problems with its narrow focus on snapper. Equal attention should be paid to the plight of the limpet and the hapuka, they say, and the ecosystem should be managed as a whole, rather than managing individual species in isolation.
Sea Change maintains it’s certainly possible to return the Gulf to a healthier state, starting with the common ground: everyone wants to be able to catch more fish, to see more life and enjoy cleaner water. What counts now is what we do next, and those choices will determine the future health of the Hauraki Gulf.
Sea Change: www.seachange.org.nz