'Degraded' bays better option
Environmental scientist Shaw Mead is surprised that New Zealand King Salmon has applied to farm salmon at some of the most pristine sites in the Marlborough Sounds.
Dr Mead gave evidence for the Nelson Underwater Club, at an Environmental Protection Authority hearing in Blenheim yesterday.
Most new farms planned by King Salmon are in deep, high flow sites where the company says conditions are ideal for farming salmon and currents will wash pollution away.
However, Dr Shaw said he would prefer fish farms to be developed in sheltered bays where the seabed was already degraded.
He was especially worried that no modelling had been done of where sediment from the proposed farms would end up.
"It is a lot of work trying to get nutrients [pollution] out of marine areas and here we are wanting to put them in again," Dr Mead said.
Board chairman Judge Gordon Whiting asked Dr Mead to draft a condition ensuring that effects of sediment falling on ecologically significant sites away from the farm were properly monitored.
The board had to look at effects, ways management should be adapted to overcome these effects and possible mitigation, Judge Whiting said.
Dr Mead suggested that King Salmon be required to collect data using techniques including photography, video, transects, quadrants and, if possible, core sampling.
Stopping monitoring after three years as draft conditions suggested would not be wise because the Sounds was not a static environment, he said.
Closed waterways and low currents in the Sounds meant there was a high chance of pollution accumulating. Proposed conditions were aimed at maximising fish productivity rather than protecting the environment, he said.
King Salmon has claimed its monitoring shows ecologically significant reefs near its existing farms have not been affected. Dr Mead said it was difficult to judge how species diversity and richness had changed from photographs provided in its evidence.
There was a worldwide push to locate farms on the coast where waste would not accumulate, Dr Mead said.
King Salmon operations and contracts manager Mark Gillard said his personal preference was for offshore farming but the company could not afford to wait for the technology to be developed.
The Marlborough Express