"A key issue centres on poaching - we believe that the setting up of a legitimate commercial market for trout would inevitably result in a black market like that for paua."
He said fish populations could be affected, as well as the money generated from trout angling and related tourism.
"It also harms local businesses and communities which depend on the millions of dollars trout angling and tourism generates for these regions."
He said anti-poaching efforts were funded from Fish and Game licence holders, with no support from local or central government.
"This would impact on the organisation's ability to deliver other critical species and habitat management programmes."
Mrs Lewis said any changes to legislation around trout farming would be a long way off.
"One of the purposes of the Regional Growth Study was to identify the key opportunities for the region, and any obstacles - such as existing legislation - that may be in place preventing these opportunities from coming to fruition. Obviously the potential to develop commercial trout farming would require a change in legislation, which is a decision that would need to be made by central Government."
Land-based Fishing Adventure owner Neville Raethel said there was a lot of opposition to the idea within the angling community, but he was yet to make a stand. He said commercial trout farming would "probably be a detriment" to his business.
"It's too early in the game to say whether I am or am not against it. I can see the negatives and positives. It could increase employment but also could increase poaching and the whole population of trout could become open to disease. "
- You can read the Regional Growth Study and provide input at http://www.bayofconnections.com/regional-growth-study/.
