Sockeye salmon. (Contributed photo)

Sockeye salmon. (Contributed photo)

Salmon face serious issues with climate change

SkeenaWild talk highlights population decline and lack of genetic diversity in sockeye

  • Aug. 8, 2019 12:00 a.m.

Salmon likely won’t disappear from the Skeena any time soon, but there are still serious issues facing multiple species within the watershed.

That was the main message at a talk hosted by SkeenaWild Conservation Trust (SWCT) at the Old Church in Smithers July 31.

“Salmon, Climate Change And What You Can Do” was billed as a discussion on how climate change is affecting local salmon stocks and what individuals can do on a personal level to address the issues.

The talk was run by Michael Price, a Salmon ecologist who works with SWCT with a specific interest in threats to salmon stocks and ecosystems.

Most of the data focused on in the presentation was pertaining to sockeye salmon, as Price noted it was the one species they had data on going back to the 1960s.

And while he did stress the situation was perhaps not as bad as he had heard others characterize it as, he did acknowledge there has been a large decline in wild sockeye salmon stocks going all the way back to the 1920s.

Those declines are less pronounced when looking at overall levels, however, due to the introduction of three spawning channels on the Babine.

And while those channels have been successful in helping keep population levels relatively static, they have also contributed to an overall lack of genetic diversity in the Skeena’s current sockeye population.

As part of his research, Price noted he has a strong interest in trying to obtain accurate data going further back — ideally to the early 1900s when the commercial fishery was just beginning — to see just how large and genetically diverse populations might have been back then.

He added that while no population is 100 per cent healthy, local chum and chinook salmon populations are doing relatively worse off than coho, cockeye and pink salmon populations.

During the presentation Price also discussed research that analyzed the genetic information of some 5,000 fish scales obtained between the years of 1913-1947 for the purpose of trying to determine the historical size and range of their populations and spawning grounds.

What it found was 13 unique population complexes of sockeye that represent the 13 major spawning tributaries in the Skeena watershed.

As for today’s population estimates for those same tributaries? All estimates are declining.

The Babine, for example, is down to some 400,000 Sockeye, from well over one million.

Many other smaller tributaries are down to below 10,000 or, in some cases, less than 1,000.

Price said the data is hard to misinterpret.

“Really what this data suggests is that … all populations of sockeye salmon, at least, are in trouble and deserving of recovery plans or rebuilding plans.”

But posing the crucial question of whether or not populations had the strength in numbers and diversity to survive potential future changes to the climate, Price expressed cautious optimism.

“At least for Sockeye we haven’t lost any of the major spawning tributaries … yes they are diminished in abundance and diversity, but they are still present.”

During the question-and-answer portion of the event, he responded to a question from Smithers Mayor and NDP candidate for the federal riding of Skeena-Bulkley Valley Taylor Bachrach on the potential effects of climate change on the traditional habitat range of salmon.

Discussing a slide shown by Price which hypothesized a much smaller and more northern summer range for salmon if current climate trends continue, Bachrach expressed concerns about salmon’s ability to make it back to the Skeena if the trip keeps getting longer and longer.

“Is that possible,” Bachrach asked?

“That’s a good question … we are starting to see, at least over the last half-dozen years, leaner fish and so [if] they are using up more of their energy reserves because they’re having to migrate further … that could be the case,” said Price.

Price added it’s possible if salmon were forced too far north they may not have the energy reserves to get back, but cautioned that, to his knowledge, no one had quantified any sort of data like this yet.

Smithers Interior News