The move has alarmed New Zealand anglers, who fear that if farm-raised trout start showing up in meat markets, it won't be long before big, wild trout become the target of poachers - and diseases spread from domestic to wild fish.

"At the present time it is illegal to sell trout, imported or local, on the New Zealand market. The current government wants to change that, and if the law is changed so that trout could be imported there is no known way of identifying whether trout on sale in New Zealand outlets is imported - or local trout which has been poached," states the New Zealand Federation of Freshwater Anglers in a notice to fishermen.

"We have every reason to believe that like paua and crayfish and deer and snapper, once trout are commercialized, there will be a substantial increase in the incidence of poaching. Those government agencies which have the responsibility to eradicate or control poaching of those species already poached have shown themselves incapable of controlling that poaching and we have no reason to believe they will be any more successful with trout," states the Federation.

"Fish and Game NZ believe that should trout become commercialized, they would not have the resources to protect our rivers, back country and headwaters from this threat.

"If it were made legally possible to import and sell trout in New Zealand there is no logical reason to ban trout farming in New Zealand. That type of fish farming, as well as being environmentally unsustainable, has been highlighted overseas by disease outbreak, pollution of the environment, misuse of chemicals to control disease and parasites, and the use of suspect animal foods," states the Federation bulletin.

"The production of trout as a food commodity is inevitably followed by a loss of access to recreational fishing waters, wild fish kills caused by both pollution and introduced disease, a huge and commercial scale poaching industry, and because of escapes of farmed fish, the loss of the genetic integrity and vigour of wild trout."

The Federation says the Canadian government has been threatening to take a complaint against New Zealand before the World Trade Organization unless the ban on trout imports is lifted.

"The current (NZ) government are prepared to 'roll over' and allow this to happen," warns the Federation, which urges concerned anglers to write to politicians, including Helen Clarke, the Prime Minister, whose e-mail address is: pm@ministers.govt.nz

"If you are as angry about this senseless and ideologically-driven threat to our recreational fishery as we are, we urge you to support our fight against it," states the Federation.