Scientist says salmon farms pose "little environmental risk"

A leading Canadian-born aquaculture scientist is supporting assertions by Marlborough-based NZ King Salmon that its planned expansion is environmentally responsible.

In a recent interview with the Nelson Mail[1], NIWA scientist Dr Andrew Forsythe says the company’s proposed scale of salmon farming was of little risk.

He says linking human waste to discharge from fish farms is “a flawed comparison” and the scientific community had done a “great deal of monitoring” in the Sounds.

NZ King Salmon CEO Grant Rosewarne says Dr Forsythe’s comments clearly debunk key claims by groups opposed to his company’s plans.

“People with much less scientific background have claimed our new farms would lead to nitrogen pollution and that there is little research on the effects of salmon farming in the Sounds,” Mr Rosewarne says.

“But Dr Forsythe says human waste contains a lot of noxious materials and is relatively low in nitrogen and the scale of salmon farming proposed by our company is of little environmental risk.

“He says NIWA has done a great deal of monitoring of environmental effects in Pelorus Sound and in a highly mixed situation you can’t detect any nutrient enrichment 100 metres from a salmon farm,” Mr Rosewarne says.

“Comments in the media report confirm what we have been saying all along - that Cook Strait tends to be much more nutrient-rich. The drivers of change in nutrient levels in the Sounds are what is occurring in the ocean and the river flows, not what the salmon farms are doing.

“Dr Forsythe also supports what is obvious to everyone bar the vocal minority that it is not in the salmon farmer’s interests to farm badly,” Mr Rosewarne says.

Dr Forsythe is a veterinarian from Canada with more than 20 years of aquaculture industry experience from North America and Europe. He has worked in salmon farming and environmental science in his home country.

Mr Rosewarne acknowledges everything humans do in the environment has an effect.

“But the issue is what you do about it to minimise that effect. We have robust management practises and been successfully farming in the Sounds for 25 years without any environmental effect remote from our farms.

“Comments from such a qualified source as Dr Forsythe should allay any fears Marlburians might have about our guardianship of the environment in which we grow our prized salmon.”

Mr Rosewarne says the company’s expansion plans provide a “unique opportunity” to create new local jobs and grow the Marlborough economy.