By Dr. Sean Brillant
Aquaculture has been active in Canada since the 1980s. There are now several species of fish and shellfish currently being raised for consumption across Canada, but Atlantic salmon is by far the largest produced and the greatest value. The vast majority of these salmon are raised in the ocean waters of British Columbia (where it is not a native species), New Brunswick, Newfoundland and Labrador and Nova Scotia.
Atlantic salmon are held and grown in cages that float in the ocean (essentially they’re open-pens). These are usually located in areas where they are protected from storms but have good water flow. As a result they are often placed in sheltered bays or near the mouths of rivers.
In Poor Health
As with large-scale farming practices of any animal, salmon aquaculture (often called finfish aquaculture) requires maintaining animals in large densities, providing them with food, and treating them with pharmaceuticals to maintain their health under these unnatural conditions. Unlike land-based farming practices however, diseases, parasites, and food and pharmaceutical waste from finfish aquaculture operations freely flow from the open-pens into the surrounding marine environment.
The various effects of aquaculture on the environment are a large concern, particularly the potential negative effects on nearby populations of wild salmon. Many populations of Atlantic salmon in NB and NS and several Pacific salmon species are at risk of extinction according to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), so the risks from open-pen salmon aquaculture are especially important.
Cracking the Books Open
To ensure we are evaluating aquaculture with substantiated knowledge, CWF did a detailed examination of the scientific literature on the environmental effects of salmon aquaculture. Some studies showed no significant environmental effect, while other did. The logical conclusion is that we can reject the assumption that open-pen finfish aquaculture has no effect on the environment; clearly, it does under some (even well-managed) conditions and in some locations. If this is incorrect, then at best, we have failed to show adequately that finfish aquaculture does not harm wild salmon populations. But, at worst, aquaculture may be destroying our wild salmon populations without our knowledge.
In this state of ignorance, it is safe to conclude that we are not acting precautious by allowing this industry to develop and to expand.
Ending the Trend
Thus, recognizing the economic benefits of finfish aquaculture, the Canadian Wildlife Federation and its Board of Directors, wants to end to open-pen finfish aquaculture on both coasts of Canada in the next 10 years and, in the meantime, a moratorium on new finfish aquaculture operations. This position is in alignment with the conclusions of many other agencies concerned with the state of wildlife in Canada including Atlantic Salmon Federation, the Royal Society of Canada, and the federally appointed Commission of Inquiry into the Decline of Sockeye Salmon in the Fraser River (i.e. the Cohen Commission).