Kiwi farmer looks at going down under Down Under
A New Zealand salmon farmer is looking at the possibility of using submersible cages in open water to overcome restrictions on expansion.
New Zealand King Salmon chief executive Grant Rosewarne believes the Cook Strait that separates New Zeland’s North and South Islands has the capacity for at least 100,000 tonnes.
The company currently produces around 8,000 tonnes of king (Chinook) salmon annually, using nine sites in the Marlborough Sounds, and has struggled with permissions both to expand and relocate its current operations in that area.
Rosewarne was speaking to a reporter from New Zealand’s Newsroom website at last week’s Aquavision conference in Stavanger, Norway.
“Every (Cook Strait-based fish-farming) pen can produce a thousand tonnes, so could we fit 100 pens in there,” Newsroom reported Rosewarne saying. “Every pen is about half a surface hectare, so you'd need probably 400 surface hectares - the size of a reasonable-sized land farm.
“But the value that would be produced would be exponentially greater.”
Deployment of the first such pens was perhaps up to five years away and would require extensive testing first, he said.
“We'd probably start by putting a pen out there (in Cook Strait) and see what happens, not even put any fish in it, see if we can make it go up and down, see how we go with storms,” Rosewarne told Newsroom.
He said the company would need to find sites in the often rough waters of the strait that offered some shelter, were deep enough to ride out the biggest waves while submerged, and were in areas where cold currents were prevalent.
