The Government’s aquaculture strategy has the bold aim of a five-fold increase in annual sales from $600 million to $3 billion.

It is less forthcoming on exactly how that might be achieved.

Based on current annual sales, a strong record of growth and opportunities for transformational development, there is the prospect of a $3 billion industry by 2035, Fisheries Minister Stuart Nash told Aquaculture New Zealand’s annual conference last month.

So how realistic is that?

Or is it a wishful aim, like Predator Free New Zealand by 2050, that few, if any, of the present players will be around to be judged on.

The projection is not broken down in the accompanying Aquaculture Strategy document but for it to be realistic, a huge expansion in farmed salmon will have to be the key.

“Aquaculture can be extremely valuable for the space it uses,” the strategy says.

“A 10-hectare salmon farm can be worth $140 million in annual revenue.”

The comparative returns on similar space are calculated as $850,000 for mussels, $800,000 for oysters and kiwifruit, $77,000 for dairy and a mere $8500 for sheep and beef.

Frozen half shell mussels were the main aquaculture export in 2018, making up half the total and returning $230 million.

Salmon was at number two, representing 17 percent of the total, followed by mussel oil, frozen whole mussels and frozen oysters.

The sector provides at least 3000 jobs throughout the country.

The major aquaculture areas – Northland, Auckland, Coromandel, Tasman and Golden bays, Marlborough, Canterbury and Southland – have averaged an annual seven percent growth since 2012.

It took 40 years for mussels to achieve an annual 100,000 tonne production and “many areas have reached their social carrying capacity”.

Open ocean farming in cooler, deeper waters away from competing uses is seen as the way of the future.

The only current open water mussel farm is operated by Opotiki-based Whakatohea in the eastern Bay of Plenty, which has received support from the Provincial Growth Fund.

Several other sites have been identified and the local authority is supportive.

“The Government will lead development of a framework to manage open ocean farming,” the strategy says.

“The technology to farm salmon and other fish in the open ocean is advancing rapidly and expected to be commercialised within 10 years.”

Its biggest advocate is King Salmon chief executive Grant Rosewarne, currently seeking resource consent for a farm in the open ocean north of Marlborough in Cook Strait.

The farm’s potential capacity is 4000 tonnes, about half the existing production from nine farms in the Sounds.

A second farm of equal size is proposed.

A proposal to relocate existing farms to more suitable waters has been before the Fisheries Minister since last year.

There is potential for greater development on land as well, with expansion of aquaculture hatcheries.

This includes rearing juveniles that could better withstand climate change, ocean acidification or pests and diseases.

Macro-algae farming to provide ecosystem services, buffering ocean acidification and storing carbon is seen as another opportunity.

The strategy does not specify a financial commitment from government but substantial investment would be essential.

Just as Landcorp was formed to develop marginal farming land, an Aquacorp with a similar brief would be an ideal vehicle.

The strategy success will be judged across four measures – sector value, regional jobs and income, emissions and waste and adverse environmental effects.

A similar visionary strategy for the wild catch sector, which currently returns more than double aquaculture’s export earnings, is awaited.