Posted on February 22, 2011
Secret of sockeye’s decline? Too many fish to the spawning grounds may be the surprising answer
The beleaguered Cohen Commission into the decline of the Fraser River sockeye may have solved the riddle of salmon depletion just days after securing a one-year extension to continue its costly inquiry.
Contrary to long-standing fisheries department dogma, the massive “overescapements” of fish to the spawning grounds, far above the numbers required to sustain the runs, are actually depressing returns, not increasing them.
But this startling news has not reached the mainstream media or even the blogosphere because coverage of inquiry’s work, which is proceeding in a quiet courtroom on the eighth floor of 701 West Georgia, is virtually non-existent. (The Globe and Mail‘s Mark Hume is an exception and was present Feb. 22.)
During key testimony Feb. 9 and 10, eminent fisheries biologist Carl Walters revised his long-held view that “overescapement” of salmon to the spawning beds had no impact on future runs’ productivity.
Inspired by Walters and others, fisheries managers shut down salmon fisheries completely, driving up escapement of strong runs, to protect “weak stocks” that have never been big contributors to the harvest. Despite the huge escapements, run strength continued to decline until last summer’s completely unexpected bonanza. (That exception may prove the rule. For various reasons, modest escapements in 2007 seem to have generated a once-in-100-years payoff.)
Now Walters’ view is closer to this recent paper from Alaska, which found that long-term yields decreased when escapement goals were exceeded. In the world of salmon biology, this reversal is akin to Kevin Falcon suddenly endorsing the NDP.
“So what?” you may ask. “Why is this in a civic affairs blog?”
According to my old friend Dennis Brown, who testified in a brief panel discussion of commercial fishing interests Feb. 22, those overescapements on the Fraser amounted to 25 million more fish which could have been harvested between 1995 and 2009 “without any damage to weak stocks.” That’s hundreds of millions of dollars of lost income for commercial fishers, the sport fleet, First Nations and local fish processors like Canadian Fish, which still maintains its cannery at the north foot of Gore.
A sustainable, green economy? Yes, and wild sockeye can be part of the solution.