We’ve had a lot of fun with Ms. Alexandra Morton’s ridiculous use of one particular graph to claim that salmon farms in BC brought about a decline in wild salmon productivity.
Without any context, her argument sounds reasonable.
Recently, DFO released its 2012 projections for Fraser River sockeye, estimating a 90 per cent probability of a maximum run size of 6.6 million.
Their predictions are summarized in a graph, including an estimate of the productivity of this year’s run, placing it just above the average.
This is, incidentally, the same graph Ms. Morton uses, but with all the context included.
See that? 2012 will likely be an average year.
What does that mean?
It means Ms. Morton’s predictions of doom and gloom are, once again, false prophecies.
Salmon runs fluctuate, and have done so ever since we started recording these numbers half a century ago.
In fact, according to recent research in Alaska, salmon runs have fluctuated for more than 2,000 years.
Humans have been impacting Fraser sockeye stocks and the stocks of every other kind of salmon in B.C. for thousands of years, and our impacts have increased ever since we started catching salmon in massive amounts and damaging their habitat more than a century ago.
But it seems apparent that ocean conditions have far more long-term impacts on salmon.
But Ms. Morton and anti-salmon activists don’t care about those facts. They focus on a small window in time and on one river system, asking, why did Fraser sockeye productivity decline for roughly 20 years starting in the 1990s?
It was salmon farms, they say, answering their own question and fingering the “new kid on the block” before anyone can raise any other possibilities or use science.
In contrast to their easy answers to hard questions, a scientific approach requires we look at as many possible factors as we can find.
What did cause the decline of Fraser sockeye productivity in the 1990s and 2000s?
Was it an explosion of Alaskan ranched fish entering the North Pacific feeding grounds in the early 1990s? Take a look at this graph.
Was it ocean temperatures? The ocean has gotten hotter since the 1950s. Interestingly, the decline in temperatures in the 1960s could be correlated with the dip in Fraser sockeye productivity at the same time. But the rise above average (0) since about 1990 can also be correlated with the decline in productivity in the 1990s and 2000s.
Was it The Pacific Decadal Oscillation? The natural fluctuation of ocean temperatures, which changes every 15-30 years? Interestingly, the brief change in the 1960s can be correlated with the decline in Fraser sockeye productivity at the same time, and the major shift from a long-term trend in the 1970s and 1980s to quick fluctuations in the 1990s and 2000s can be correlated to the long-term stability of Fraser sockeye productivity in the 1970s and 1980s, and the wild fluctuations and decline in the 1990s and 2000s.
Was it any of these things? All of these things? None of these things? We don’t know. We haven’t even included catch data in this post, that has to be considered as well. But it sure looks like ocean conditions have way more impacts than a few salmon farms ever could.
Plus, there is actually evidence to suggest that ocean conditions do have impacts (in contrast to the speculations and simplistic correlations anti-salmon farming activists use to support their claims).
But we can’t say for sure.
One thing we know for sure, however, is that, given all these factors which could affect Fraser sockeye productivity, suggesting that “salmonfarmsdidit” is a facile conclusion to the mystery, especially when we don’t even have a body.
The “corpse” of wild salmon is still swimming strong, despite all the predictions of doom and gloom, and with an average run predicted for the Fraser, exceptional runs predicted for the Alberni-Clayoquot region and good returns expected elsewhere in BC, we are confident in saying that all the evidence shows that wild and farmed salmon can coexist together in the same ocean with negligible risks to either species.
Farmed versus wild is a false choice.