FEATURE | Mussel reef restoration project in the Hauraki Gulf, NZ

A hundred years ago, New Zealand’s Hauraki Gulf played host to abundant green-lipped mussels and other shellfish in naturally occurring reefs and beds. The combination of historic overfishing and environmental degradation saw this resource ebb away.

Now, the community is working together to bring it back. Revive our Gulf – a group made up of scientists, mussel farmers, donors and community members – is taking on the task with support from the Nature Conservancy, Fisheries New Zealand, and the Department of Conservation.

The group has already placed 150 tonnes of live green-lipped mussels at a number of sites near Rotoroa Island and in Mahurangi Harbour.

All those mussels have to come from somewhere, and that’s where local businesses have come in. Mike Moy is the Operations Manager for North Island Mussels, a joint venture between Sanford and Cedenco. The company farms and processes Greenshell Mussels in the Coromandel, and, after several years of supplying mussels to the Revive our Gulf project at a reduced rate, this year generously donated the mussels required as well as harvesting time and expertise.

“There’s a pretty big stake in the mussel reef restoration for us. It’s where we farm and the business is very exposed to environmental changes that can happen. We’re dependent on looking after the area and saw this project as crucial to the heart of the gulf as well as the future success of our business,” Mike said.

Abundant mussels provide a unique win-win from the community and the environment.

A single mussel can filter up to 350 litres of seawater a day, removing sediments and contaminants from the water which improves water clarity, provides a habitat for small fish as well as food for bigger fish, stabilises the seabed and coastline, and enhances biodiversity.

Healthy, self-sustaining seafood populations are a good source of food for people too and already an abundance of life has been seen including octopus, juvenile snapper and large hermit crabs using the beds.

As a member of the Hauraki Gulf community himself, environmental sustainability is also important to Mike personally.

“Mussels, oysters and aquaculture play a key part in our local economy bringing employment, business from chartered fishering and holiday makers to spend money here. My livelihood is at the very crux of it. It’s dependent on the environment we grow mussels in.”

The gulf is also where Mike plays – he spends much of his spare time diving, fishing, swimming and surfing so his personal life also revolves around the Hauraki Gulf as well as his work one.

The ongoing mussel reef restoration has been made possible thanks to a combined NZ$400,000 in funding from Fisheries New Zealand, the Department of Conservation and international environmental organisation, The Nature Conservancy. Biosecurity protocols are followed to prevent the spread of marine pests, and this includes decontamination of mussels by soaking in fresh water before transport.