A salmon farming scientist predicts the New Zealand industry will have to start looking to new waters if it wants to grow.
Professor Kenny Black, who works at the Scottish Association for Marine Science, is in the South Island advising the Marlborough Regional Council on how to regulate salmon farming.
While many nations such as Scotland, Chile and Norway are planning to scale up their salmon farming - he said it might not be so easy in New Zealand.
Professor Black said if New Zealand wanted to expand, it would need to invest in technologies that allowed farmers to move into more open sites.
He said there's not the capacity in Marlborough Sounds for major expansion.
Professor Black said if the industry is to expand in New Zealand it will probably have to look at sites that it now considers marginal.