Local lab to test for sea lice drug-resistance
Published: February 25, 2010
Testing to determine if sea lice are becoming resistant to a chemical product used by fish farmers is expected to begin this spring in Campbell River.
“We hope to begin in April. Some people may say that’s already too late, but you have to start some place,” said Dr. Sonja Saksida of the B.C. Centre for Aquatic Health Sciences.
Alexandra Morton, a biologist, activist and opponent of open netpen salmon farms, recently raised concerns that sea lice may be becoming resistant to SLICE – a vet-prescribed chemical remedy that fish farmers use to kill naturally-occuring sea lice on Atlantic salmon.
Morton said concerns were passed on to her that sea lice were proliferating on Grieg Seafood farms located on the West Coast in the Esperanza Inlet.
“These concerns were passed along by friends and family…no one wants to go on the record because they are fearful of losing their jobs,” she said Wednesday.
According to Morton, provincial data shows that salmon on Grieg’s West Coast farms were treated with SLICE last fall, but then sea lice numbers quickly rebounded. This may indicate, she said, that the sea lice are becoming drug-resistant.
She also speculated that these drug-resistant lice may have already been introduced into Discovery Passage.
Salmon harvested on the West Coast are trucked to Campbell River and then over to the Walcan processing plant on Quadra Island.
A video taken by divers shows a dark-coloured and particulate-filled effluent coming from the Walcan outflow into Discovery Passage. Morton claimed the effluent contained sea lice, along with chunks of salmon organs, fins and scales (the video can been seen online at alexandramorton.typepad.com).
“If I’m wrong I imagine I’ll be sued, but if I’m right…,” said Morton. “There’s strong evidence of drug resistance.”
Morton added that she is not “out to get” Walcan, but is disheartened the B.C. government is doing nothing to study or identify potential problems of drug-resistance.
However, a co-owner of Walcan disputed Morton’s allegations and said the company is in full compliance of its Ministry of Environment regulation, and even passed a government environmental audit last week.
“Our job is to be in full compliance…and we believe that what we’re doing is safe,” said Bill Piery. “She (Morton) never even contacted us. Her approach is to discredit and damage us…we feel she’s more interested in telling a story then in finding out the facts.”
A representative of Grieg Seafoods also discounted the drug-resistant sea lice theory. Mia Parker, the company’s manager of regulatory affairs, said there have been drug-resistant problems with sea lice in the Atlantic Ocean which affect fish farms in Norway and Scotland, but the species of sea lice that live in the Pacific Ocean are very different.
“The vets here have noticed that the sea lice we find here are less aggressive and cause less harm (to fish) – they are genetically different,” said Parker. “Normally you’d see signs of drug resistance. We haven’t seen any signs…”
Dr. Saksida is also doubtful that West Coast sea lice are becoming drug resistant. She and another biologist recently submitted a new research paper to the Journal of Fish Diseases that addresses the topic. The study is presently being peer reviewed before it is published.
“We have five years of sea lice treatment data from the farms…it doesn’t look like there are any issues of resistance,” she said.
Dr. Saksida also doubted if sea lice could survive the journey of harvesting, transport and processing, and emerge alive at the end of an outflow in Discovery Passage.
Nevertheless, testing for drug resistance – hopefully using sea lice captured from both the west and east coasts of Vancouver Island – is expected to begin April. It’s something that needs to be done, according to both Parker and Morton.
“It’s a good idea, but a little bit late,” said Morton.