Salmon farmer balances farm growth with ecological sustainability

Akaroa Salmon's ocean farm floats discreetly in a tranquil bay near the heads of Akaroa harbour.

Seventeen huge round netted pens are home to thousands of King salmon of varying sizes.

A couple of boats go from one pen to the next, cleaning nets and feeding the fish.

A stone's throw away, rugged farmland and bush-covered hills climb steeply above the teal blue water.  

The sound of the lapping tide and the squawk of seagulls is suddenly drowned out by a feeding gun.

The surface water in a pen comes alive with splashing as hundreds of salmon chase the falling food.  

Duncan Bates built the farm with his father Tom from scratch nearly four decades ago.

"We didn't have a lot of capital to start the business, but I was lucky enough to get a loan from the Rural Bank so we had to learn to do most things ourselves," Duncan proudly says.

The farm began operating in 1986 with one pen which Duncan built with help from a local engineering business.

He towed it out to Lucas Bay, the council approved aqua farm site near Wainui.

"I did the salmon farming and feeding of the fish," Duncan says.

"I used to drive out to land's end and then walk down the hill. I had a little wooden dingy that I'd row out to the farm on and that was the start of salmon farming."

A lot of water has passed under the ocean farm since then.

This year it will produce about 700 tonnes of King salmon and now the business employs 70 people.

"Thirteen guys out here (on the ocean farm) and then there's the processing side of the business in Christchurch and the administrative staff as well."

The 60-year-old is on the front foot when it comes to farming sustainably.

"We've introduced a monitoring programme that's made us much more proactive towards the biomasses we're farming and our feeding systems. It's just made us be much better farmers," Duncan says.

Rick Smale, the farm operations manager, says modern technology like underwater cameras is also helping to improve the farm's environmental footprint.

"The use of cameras is a pretty efficient way of making sure we're minimising the amount of waste that goes to the seafloor."

Duncan has also drafted a salmon welfare document so the industry has a consistent approach.  He says the document has had buy-in from the SPCA.    

"There's only one thing that we're at odds with, they want us to introduce a camera recording of the actual harvest happening. Logistically that's quite challenging, but we'll figure out a way of doing it."

After nearly 40 years of salmon farming, Mr Bates reckons his long-term vision is just about complete.

"I believe that we've got the ability to grow 1000 tonnes here on these sites  and do it sustainably and do it really well and we're just about there."