From this map: http://www.agf.gov.bc.ca/fisheries/Finfish/cabinet/marine_fishfarms.pdf
There is 1 fish farm (1136 - Shaw Point) that is in the path from the spawning grounds to the open ocean.
(The purple triangles are applications)
Perhaps that farm is using "SLICE" a form of injested pesticide that kills sea lice. See
http://www.farmedanddangerous.org/page/sealicechemical SLICE
One of the most significant and well-studied impacts of salmon farming on wild salmon is the transfer of sea lice from fish farms to juvenile wild salmon during out-migration. Attempts to control sea lice outbreaks on salmon farms by industry and government have been through emamectin benzoate, sold under the commercial name SLICE.
Emamectin benzoate, the active ingredient in SLICE, is a pesticide that is administered to farmed fish through their feed. In BC, there is a withdrawal period of 68 days between when SLICE can be administered and fish can be harvested for human consumption.2
To date, SLICE has:
* not been tested for food safety by the Canadian Food Inspection Agency
* not been licensed by Health Canada; or
* not been permitted for use through the Pesticide Control Act
Yet, SLICE is still the preferred chemical for sea lice control in Canada. In BC, salmon farmers are approved to use SLICE through the Emergency Drug Release Program which allows the use of non-approved drugs when recommended by veterinarians for emergency situations.
SLICE is not used for the occasional emergency. Outbreaks of sea lice are so prevalent in industrial net-pens that the use of SLICE has become standard operating procedure. In 2003, 37 million farmed salmon in Canada were treated with SLICE. A steady dependence on SLICE by the BC salmon farming industry has been recorded by the Ministry of Agriculture and Lands.3
Emamectin benzoate belongs to a class of chemicals called avermectins, which are axonic poisons affecting nerve cells.4 Farmed fish ingest SLICE as a coating on commercial food pellets. Digestion releases the drug to pass through the lining of the fish’s gut and into the fish’s tissues, from where it takes about a week to be eliminated.5 Although SLICE contains emamectin benzoate (0.2%), an active ingredient in pesticides, it is classified as a drug because it is fed to the fish rather than applied externally.
Overuse or over-reliance on any single compound has been shown to lead to the development of resistance by the target organism. Evidence of resistance to SLICE has recently been reported in Chile.
SLICE lacks specificity; it puts marine organisms in the vicinity of treated salmon farms at risk. A report commissioned by the World Wildlife Fund’s Salmon Aquaculture Dialogue (SAD) found that sea lice therapeutants (such as SLICE) negatively impact the environment through its effects on non-target wild crustaceans such as shrimp, crabs and prawns, and may remain in the environment from ten days to six months.
Makes me want to go out and buy some farmed salmon for dinner tonight.... not!
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Topic: The salmon farm thread (Read 18566 times)