What is the difference between 'ranched' and 'farmed' salmon?
Due to many reasons including over-harvest, wild salmon populations declined in the latter part of the 20th century. It was soon realized that if an ever increasing human population is going to take from the ocean, it better give back. Just like on land, we started to 'farm' the ocean.
Salmon farming and salmon ranching have the same goal - grow salmon to provide a healthy protein to the consumer. Both methods of aquaculture hatch eggs which are raised in a freshwater hatchery facility and both methods move fish from freshwater to saltwater net pens to continue growth.
Whereas salmon farmers culture their fish for its entire lifecycle, eventuallly harvesting them directly from the net pen in which they were raised; salmon ranchers release their fish from the net pens to complete growth in the open ocean. As ranched salmon instinctively remember where they were born, they will return to where they were "imprinted" to be harvested by traditional fishing boats.
Salmon farming is common in Chile, Norway, Scotland, Ireland, Faroe Islands, Tasmania, New Zealand and Canada. Salmon ranching is practiced in Alaska, Japan, Korea and Russia.
Globally, salmon farms provide about 300 million fish, and salmon ranching produces about 220 million fish for human consumption each year.
What are the risks of ranching or farming salmon?
Whether salmon ranching or salmon farming, the benefits of growing salmon for human consumption are clear - providing a healthy and efficient protein without additional strain on natural, wild salmon populations. But, as with any food production, there are also risks. There are three main risks shared by both methods of salmon culture:
Salmon consume fish meal which can place additional strain on those fish lower in the food chain.
Farming and ranching produce organic waste (fish poop and processing waste) which need to be properly managed.
There is genetic risk of cultured salmon interbreeding with its wild counterpart and the potential for lowering the performance of its wild cousin.
Salmon farmers and salmon ranchers worldwide are very aware of these risks and are always looking at new ways of operating to ensure these risks are well managed.