Questions and answers about Overwaitea's closed-containment salmon | Sustainable fisheries and aquaculture | Oceans | Science & policy | Sustainable fisheries and aquaculture | Issues
Photo: Questions and answers about Overwaitea's closed-containment salmon

Overwaitea stores are now stocking sustainable closed containment salmon.

1. Why is this farmed salmon more sustainable than other farmed salmon?

This coho salmon was raised in a land-based closed containment operation that has received a "Best Choice" ranking for environmental sustainability. Closed systems separate farmed fish from wild fish and the environment, containing the fish and water within the farm rather than releasing them into the environment. Waste, escapes, and spread of disease and parasites are much better controlled in these systems.

2. Why doesn't everyone produce salmon this way if it's so much better for the environment?

Closed containment technology is developing rapidly and is being used for salmon and many other types of fish. With increasing demand for sustainable seafood we expect to see an increasing shift toward adoption of closed containment technology. The existing industry has resisted changes to its farming practices and business model, which is one reason this move by Overawaitea is so important; it shows that a major seafood buyer will embrace fish produced this way and adds incentives for others to do so.

3. Some people say this salmon isn't better for the environment because it has a larger carbon footprint. Is this true?

A frequently cited study on the energy use of closed containment looked at an extremely outdated experimental closed system, but at present there may still be a bigger carbon footprint from many closed containment operations. However, improved technology continues to greatly improve the energy performance of closed containment systems and alternative energy sources offer promising ways to further reduce the carbon footprint. Some closed-system operators are experimenting with generating energy from their waste to power their operations, like some sewage facilities. The closed system is also on the hydro grid instead of using diesel generators and has reduced transportation for personnel, materiel, and product. This is one challenge that is likely overstated and can be solved, while there are no credible solutions to the real and immediate problems of farmed salmon harming wild salmon and the environment, especially around disease, sea lice and escapes.

4. What does sustainable mean anyways?

The definition used by major sustainable seafood programs is: fish or shellfish that is caught or farmed in ways that consider the long-term viability of harvested populations and the ocean's health and ecological integrity.

5. Does this salmon taste different?

Chef Robert Clark of Vancouver's C Restaurant says, "This salmon, similar to Atlantic farmed salmon, has a somewhat lighter, less fishy taste than wild salmon."

6. Is it more expensive?

Overwaitea is selling the closed containment salmon for the same price as other farmed salmon. Even if there is an increased cost it is because this salmon farm is actually paying the full cost of growing these fish instead of letting wild salmon and the environment bear the cost. If it isn't more expensive, then it is amazing that this salmon can be produced at a competitive price considering that, unlike with open net cages, these producers must pay the full cost of waste disposal, disease control and preventing escapes.

7. What is in the feed?

SweetSpring uses a feed that as very high levels of plant-based material instead of relying heavily on fish meal and fish oil and the closed containment technology allows improved feed efficiency because the growing environment can be better controlled. They still use some fish inputs for the health of the fish and to get the omega 3 content consumers want. But the analysis is that they grow one kilogram of farmed fish from 1.2 kilograms of wild fish inputs. Compare this to the global numbers of anywhere from two to eight kilograms of wild fish to get one kilogram of farmed and you can see that on this front too there is a huge improvement over the status quo.

http://www.davidsuzuki.org/issues/oceans/science/sustainable-fisheries-and-aquaculture/questions-and-answers-about-overwaiteas-closed-containment-salmon/

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