Co-Operation To Beat Sea Lice In Salmon

Ground zero for BC's fish-farm battles is Broughton Archipelago, where salmon farms are bang in the middle of wild-fish migration routes. But it is also an area where aquaculture companies and environmental groups are tentatively working together for the first time, according to Times Colonist.

Marine Harvest Canada and the Coastal Alliance for Aquaculture Reform initiated an uneasy truce last year, and now fish farming companies, Grieg Seafood and Mainstream Canada, have joined an effort to reduce sea lice on farm fish and fallow some farms during out-migration of pink salmon through the archipelago.

The Broughton Archipelago Management Plan shows more can be achieved with a ceasefire than war, said Crawford Revie, Canada research chairman at the University of Prince Edward Island and a delegate at the international sea lice conference in Victoria, which ends today.

Scientists looking at lice from both sides of the fence are part of the management plan, which means advice given to policy-makers is seen as independent, Mr Revie said.

He explained: "We are seeing whether, instead of just throwing mud at each other, we can come up with pieces of reviewed science that move us beyond polarisation."

Pink salmon, which go to sea when they are tiny and lack protective scales, are particularly susceptible to sea lice. After a 97 per cent crash of stocks in 2002, scientist Marty Krkosek of the University of Washington warned some stocks were likely to become extinct unless action was taken.

Last year, Marine Harvest treated Broughton farms with the pesticide, Slice, before out-migration of pinks, and farms on one migration corridor were fallowed. This year, another migration corridor is being left fallow.

It is not yet known what the effect will be on pink returns but levels of lice have dropped, said Craig Orr, executive director of the Watershed Watch Salmon Society and a member of the Coastal Alliance for Aquaculture Reform.

"There are indications that the management actions creating a corridor are reducing infection pressures," he said.

Dr Krkosek is monitoring the wild fish and Revie is monitoring farm fish.

However, Mr Orr warned that Slice treatments and fallowing are temporary solutions and moving farms to closed containment is the permanent solution.

He said: "We have to get farms out of the water and get them on land. We must put a wall between the farm fish and the environment."

Marine Harvest is working on a closed-containment pilot project, but land-based salmon farms are not yet operating on a commercial scale, reports Times Colonist.

Mr Revie warned closed containment presents its own problems. The carbon footprint is larger and closed containment could consign fish to a quality of life similar to that of battery chickens, he said.

Meanwhile, conservation biologist Michael Price, who works with Raincoast Conservation Society and presented a research paper at the conference, wants to see similar migration corridors cleared for sockeye in the Discovery Islands, where the majority of the troubled Fraser stocks out-migrate.

There is little research on the effect of lice on sockeye, which do not go to sea until they are larger, and so are less susceptible to lice.

"But when a small fish is just starting its migration, [lice] are unlikely to be beneficial and we are talking about an endangered species," he said. "We are not saying these lice have caused the [sockeye] collapse, but there is a heightened urgency to understand all the threats."