Why has one group of sockeye salmon from the Fraser River system experienced a growth in productivity over the past decade while other Fraser River stocks have declined?
Storytellers playing scientist have tried to convince people Harrison River sockeye don`t pass salmon farms when they migrate north, therefore they are doing well simply because they don’t pass salmon farms. This explains everything if you’re already predisposed to blame salmon farms for everything and accept simple answers to tough questions.
It’s true that at least some Harrison sockeye migrate out of the river delta and go along the West Coast of Vancouver Island, unlike most other stocks which generally migrate along the East Coast of Vancouver Island.
However, as usual with activism-driven science claims, there`s a lot more to the story.
But the most important piece of the puzzle is that Harrison sockeye have a very different life strategy than other salmon stocks.
Unlike other sockeye, which feed and grow in lakes for several years before going to sea, Harrison sockeye go to sea shortly after they emerge from the gravel where they hatched. They are in the ocean nearly a year earlier than other sockeye stocks. This may give them an advantage in early marine survival growth, occupying a niche that few other species do. They may enjoy better feeding conditions as fry and juveniles, less competition for food and less threats from predators.
Let’s say that again. A significant amount of Harrison River sockeye winter off the West Coast of Vancouver Island when they are very small, young and vulnerable.
There are approximately 30 active salmon farms on the West Coast of Vancouver Island, from Quatsino Sound south to Alberni Inlet. Clearly they are not having any negative impacts on wintering Harrison sockeye, not even when they are at a young and vulnerable stage.
The Harrison sockeye appear to have developed a very successful survival strategy, and it appears it co-exists very well with salmon farms. More research is needed to explore this connection.
More resources: This map shows all the registered salmon farm and hatchery tenures in B.C. However, many of the sites on the list have been inactive for years or have been rescinded by the provincial government. Typically, there are about 70 active farms in British Columbia.