Another huge sockeye salmon run is forecast to return to the Fraser River this summer, potentially even bigger than the modern record of 30 million that unexpectedly came back in 2010.
The fish that are now on their homeward migration back to B.C. waters are the spawn of that massive run four years ago, which was the best in a century.
Pre-season estimates of this summer’s run size from the Department of Fisheries and Oceans range from a low of 7.3 million to a high of 72.5 million, with the more probable mid-range forecast set at 23 million.
Until the salmon begin appearing off Vancouver Island, however, there’s little way to know with certainty what proportion of fry that went out to sea survived and thrived in the marine environment.
Much depends on ocean conditions, such as water temperature and the amount of food and predators they encountered.
It’s been theorized that iron-rich ash from the eruption of an Alaskan volcano in 2008 caused a plankton bloom that increased the food supply, contributing to the 2010 sockeye run.
No volcano fertilized the North Pacific waters since then, but salmon watchers are waiting to see if a rogue geoengineering project had any similar effect.
A Haida-led team controversially dumped 200 tonnes of iron dust in the ocean in 2011 with the aim of trapping atmospheric carbon and boosting salmon returns. A 10,000-square-kilometre plankton bloom was later detected by satellites.
Commercial harvesters, sport fishing operators and aboriginal fishermen, meanwhile, are all buzzing with anticipation over the potential run.
But processors caution a huge record run could overwhelm fish packing plants that were pressed to their limit in 2010.
“It was a large challenge and I’m not sure we could have handled very much more fish,” recalled Rob Morley, vice-president of production and corporate development at Canadian Fishing Co. (Canfisco).
He noted the range of 2014 estimates is broad and salmon forecasting is notoriously inexact.
But Morley said other signs coming in point to a very good year for sockeye all along the coast, including runs to Barkley Sound and the Skeena River.
“We’ve seen very good returns of three-year-old fish this past summer,” he said, referring to sockeye that come back a year early and are called immature jacks.
Strong coho returns also suggest good ocean survival for sockeye.
Morley said processors hope a strong run can be verified soon enough for fishery managers to approve early and steady openings, rather than a later, more compressed window.
“If we are, in fact, seeing a lot of fish and get started sooner, it will help everybody handle more fish.”
Sto:lo Tribal Council fisheries advisor Ernie Crey warned against allowing intensive commercial fishing too soon this summer without solid justification.
“Everyone’s getting excited,” he said. “It’s great the forecast is looking that good. But we can’t forget that we’ve had three inquiries into failures of Fraser sockeye salmon runs. Things can go terribly wrong and people can be very disappointed.”
If errors are made and managers decide mid-season they’ve allowed too much fishing, Crey said, the only place to compensate and ensure enough salmon spawn is to then curtail the aboriginal catch upriver.
“It’s hard to be definitive about salmon. We only know enough to know that we don’t know enough.”
Some commercial sockeye fishing was allowed last year, when about four million salmon returned to the Fraser, after a shutdown in 2012.