OTTAWA, Canada -- The group of scientists who wrote to the Prime Minister indicating that sea lice from farmed salmon endanger wild salmon stocks unfairly expressed only one side of the story, according to Ruth Salmon, Executive Director of the Canadian Aquaculture Industry Alliance.
"While there are some studies that may support the view of these scientists, there are many other scientific studies that suggest that salmon farms in BC make little contribution to the sea lice levels that naturally occur on wild salmon," says Ruth Salmon, "For example, one recent study found that wild salmon in an area where there were no farms had as many sea lice as wild salmon in BC's Broughton Archipelago where farming occurs."
"And another recent study found exceptionally high returns of pink salmon in an area containing 16 active salmon farms - and concluded that pink salmon populations and farmed Atlantic salmon could coexist successfully," states Salmon.
After reviewing the current scientific research on the interactions between salmon and sea lice, Dr. Kenneth Brooks, Senior scientist with Aquatic Environmental Sciences, stated "To date, no direct 'cause and effect' relationship between sea lice, salmon farms and wild salmon in British Columbia has been identified by scientists who have studied the issue."
One thing that scientists do agree upon is that wild salmon carrying sea lice can infect other wild salmon. In fact, this is an essential part of the natural life cycle of sea lice. This finding has led many scientists to conclude that new infections of wild stocks originate primarily from other previously infected wild stocks - rather than from farms.
"Since juvenile farmed salmon are free from sea lice when introduced into the marine environment, it looks like the sea lice are actually coming from the wild fish onto farmed fish," says Dr. Jim Brackett, President of Aquatic Life Sciences.
It therefore remains debatable whether the transfer of sea lice from the farmed salmon to the wild salmon could be on a sufficient scale to have an impact. "Because the wild fish naturally carry sea lice, we don't know whether there is a sufficient enough transfer of lice from farm fish to wild fish to make an impact on the natural levels of infection," says Dr. Kevin Butterworth, Director of Marine Research, BC Centre for Aquatic Health Sciences, "If there is not a significant transfer of sea lice, then this whole issue is a moot point."
With the lack of a scientific consensus on this issue, the Canadian Aquaculture Industry Alliance believes that it is time for all stakeholders to engage in constructive dialogue to define environmentally, socially, and economically sustainable salmon farming methods that measurably reduce or eliminate key impacts of salmon farming. The World Wildlife Fund sponsored Salmon Aquaculture Dialogue is one forum where this type of stakeholder dialogue is occurring. Currently, over half of global farmed salmon production is represented at the Dialogue - together with environmental NGOs and researchers from every major salmon producing nation.
"A key feature of such stakeholder dialogues is that they recognize that existing science provides conflicting information related to the impacts of salmon aquaculture," says Ruth Salmon, "And rather than fostering disagreement between scientists, they focus on these areas of uncertainty - and then support scientific research to help resolve this uncertainty."
This spirit of cooperation being shown by many scientists, environmental NGOs and industry members emphasizes that the time for debate is over. Now is the time for all stakeholders to join in constructive dialogue that will allow a vibrant aquaculture industry for the benefit of Canada's coastal communities - and provide support for the ongoing efforts to protect wild salmon stocks.
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