Sea Lice and Wild Salmon

A new study looking at the infection levels of migrating juvenile pink and chum salmon as they approached and passed one salmon farm in BC's Broughton Archipelago has been published in the March 30th edition of the Proceedings of the Royal Society B. In the article, the authors note that while no general conclusions can be made on the transmission dynamics of lice from farm to wild salmon based on this study alone. However, the study authors are contacting the media to encourage interviews on the premise of the study and this has renewed interest in whether or not salmon farms are impacting wild populations in the Broughton.

It is also important for those concerned about wild salmon populations in the Broughton Archipelago to know, there is some good news. The pink salmon returns that resulted from the outward migration in the spring of 2003 (the fish the subject of this study) were near historical averages at one million fish. So while we continue to be committed to working to better understand potential interactions it is worth pointing out that the pink salmon in the Broughton have shown exceptional growth and survival in recent years.

Our Position

At the BCSFA we believe that all research makes a contribution to a fuller understanding of the potential interaction between farmed and wild salmon. Those who can remember high school science will know that conclusions cannot be drawn from one study and that is why the results of other research efforts by Department of Fisheries and Oceans and University-associated scientists are equally important - it will be the full body of work that will provide a better understanding of interaction between sea lice and farmed and wild salmon populations in British Columbia. As an industry we are committed to continuing to work with regulators, scientists and other interested parties to address this issue.

Research Activities

A great number of sea lice research studies are either underway or have been completed. For example, the BCSFA is currently sponsoring research to assess lethal infection levels on juvenile salmon - something which is not yet known - and to identify all potential sources of sea lice in the marine environment.

In addition, the British Columbia Aquaculture Research and Development Committee have supported the following studies:

• Assessing the impact of sea lice on the recruitment of pink salmon in the Broughton Archipelago and surrounding area
• Origin of sea lice on juvenile pink salmon in the Broughton Archipelago
• Interaction between sea louse Lepeophtheirus salmonis and wild and farmed salmonids: laboratory and field investigations into louse origin; susceptibility and lethal loading; using sentinel cages and biomolecular markers.
• Assessing the impact of sea lice on the recruitment of pink salmon in the Broughton Archipelago and surrounding area (winter sampling)
• 2004 North Coast Marine Baseline Survey and Sea Lice Research Program
• Use of light trap and DNA methodology to monitor intensity and origin of sea lice on wild and farmed salmon
• Estimation of the impact of sea lice infestation from fish farms on native stocks using a risk factor model
• Marine Monitoring of Sea Lice on Wild Juvenile Salmonids in Clayoquot Sound (2004-2005)
• Identifying the natural hosts of sea lice on the Broughton Archipelago area in the late fall.

June 14, 2005
"Salmon farms and wild stock can co-exist"

August 3, 2004
BC Salmon Farmers Association information on Summer 2004 preliminary sea lice sampling results

May 21, 2004
Sea Lice Low on Broughton Fish Farms, Monitoring Shows

May 12, 2004
Department of Fisheries and Oceans Statement on Sea Lice and Pacific Salmon Stocks

May 12, 2004
2003 Sea Lice/Pink Salmon marine Monitoring Program Findings - Main Conclusions of the Study

May 12, 2004
BACKGROUNDER on the DFO Research Papers on Sea Lice

February 17, 2004
Scottish study indicates sea lice medicines don't pollute environment - posted at www.intrafish.com