Over 90% of salmon die before returning to spawn — are farm-borne diseases partly to blame?
Last post we mentioned the renewed Seafood Watch rankings of BC-grown farmed salmon: red, which means “Avoid.”
David Suzuki commented on the new ratings in a recent article in Common Ground:
Salmon farming threatens some of the planet’s last remaining viable wild salmon – a keystone species that touches all our coastal ecosystems. The issues in dispute include feed ingredients, disease transmission between farms and wild salmon, bird and marine mammal deaths, pesticide and antibiotic use and the effects of multiple farms in concentrated areas.
The Monterey Bay Aquarium’s Seafood Watch program recently released science-based ranking reports on open net-cage farmed salmon in BC, Norway, Chile and Scotland. All received a “red” or “avoid buying” designation. Canada’s SeaChoice followed suit.
More than 90% of migrating juvenile salmon die before returning to freshwater to spawn, most in the first months after entering the ocean. Pathogens may be a significant factor, although not all specifics about diseases are fully known. Justice Bruce Cohen’s Commission of Inquiry investigating the decline of Fraser River sockeye included pathogen risk as a factor in the 2009 sockeye collapse. Disease from salmon farms is one risk to wild salmon that can be controlled.
Salmon farming shouldn’t be done at the expense of wild salmon. Both wild and farmed-salmon industries provide fish and create economic activity, but the province’s sports and commercial wild salmon fisheries and marine tourism contribute more to BC’s economy and quality of life than salmon farming.
Aquaculture must stop using the ocean as a free waste-treatment system. Closed-containment – in the ocean or on land – is better at controlling water and removing feces and chemicals like antibiotics and pesticides used for sea lice. One BC open net-cage company lost over $200 million in one year because of disease, enough to build 10 closed-containment farms. Yet the industry claims closed alternatives cost too much…
Read the full article.
