A cold blooded protein converting machine
Salmon, compared to most meats that we will eat, are one of the most efficient converters of feed to edible meat. The reasons for this excellent "feed conversion ratio" are;
- They are cold blooded and therefore don't waste valuable energy heating their bodies.
- They don't waste energy fighting gravity. They simply float in the water using a swim bladder that provides the right buoyancy.
- They have fewer bones than other sources meat (chicken etc) and therefore don't waste food building bones we don't eat.
Fish in and Fish out
Salmon naturally eat fish and this is replicated in the diet farmers feed their fish. Fish meal and fish oil are harvested from sustainable stocks of fish for which there is little or no demand for human consumption (anchovy, mackerel etc) and also from trimmings left over from other fish processing. This fishery doesn't just supply meal and oil to farmed salmon, but also other aquaculture species as well as the pork, poultry, hobby aquarist and pet food industries. The International Fish Meal and Fish Oil Organization (IFFO) estimates that less than 15% of the fish meal/oil goes toward salmon farming. Farmers and feed companies continue to invest a lot of research into reducing the amount of fish meal and oil required to produce a farm-raised salmon.
Activists often claim that it takes 5 kilograms of wild fish to produce 1 kilogram of farmed salmon - this is wrong. Activist websites refuse to provide the calculations used to produce this exagerated ratio. So we're going to show you the math, using recommendations from IFFO for fish meal and fish oil recovery and the current inclusion rates of fish meal and fish oil in the diet of BC farmed salmon;
(% fish meal in the diet + % fish oil in the diet) / (yield of fish meal (%) from wild fish + yield of fish oil (%) from wild fish) x Feed Conversion Rate = wild fish used
(17 + 13) / (22.5 + 5) x 1.2 = 1.31
So, it takes 1.31 kilograms of wild fish to produce 1.0 kilogram of BC farmed salmon (and this is conservative as this formula does not include the use of wild fish process trimmings in feed or the rendering of farmed salmon trimmings at the processing plant used in other food industries).
BC salmon farmers continue to advance research into feed diets to continue to reduce reliance on meal and oil derived from wild fisheries. It is a future and real goal of salmon farmers to be a net producer of fish proteins.
Which is more efficient at converting protein? Salmon ranching or salmon farming?
While most activists focus on fish meal use in salmon farming, they choose to ignore the fact that over 5 billion juvenile salmon are released each year into the ocean. These salmon are called "ranched salmon" and are intended to serve the same purpose as farm-raised salmon - human consumption. This is common practice in Japan, Russia and Alaska and are sold in the market as "wild-caught" salmon.
Although not in the form of a feed pellet, ranched salmon consume fish meal and oil - and at far greater rates than farm-raised salmon. Whereas salmon farmers are able to fine tune their fish's diet to reduce the use of fish meal and oil, wild-caught salmon eat marine proteins at a rate of 100%.
If activists were seriously concerned about the use of fish meal used to grow salmon, they would focus on salmon ranching and not salmon farming.