Sockeye returns plunge in B.C., official calls 2019 'extremely challenging'
Federal fisheries experts are painting a devastating picture of the challenges facing Pacific salmon and point to climate change as the main culprit.
A new from Fisheries and Oceans Canada found warming ocean temperatures and marine are affecting ocean food webs and causing declining salmon stocks. Fisheries staff say factors such as human activity that degrades fish habitat and a landslide on the Fraser River blocking millions of fish from spawning upstream are making things worse.
Andrew Thompson, regional director for fisheries management, says it's been an extremely challenging year for salmon and there have been significant declines in a number of stocks.
In one of the most dramatic shifts, the federal Department of Fisheries has adjusted the estimated number of returning Fraser River sockeye to slightly more than 600,000, down from an earlier projection of nearly five million.
Sue Grant, head of a federal program on the state of salmon and author of the report, says some of the declines are residual effects of larger climate change events.
Less freshwater the better
But it is not just the climate impact on oceans that is stressing B.C. salmon.
Fresh water ecosystems are also feeling the brunt of climate change with more landslides and forest fires. That combines with human activity such as development and deforestation to hurt the health of these critical salmon habitats.
Grant said salmon that spend less time in freshwater, such as pink, chum, river-type sockeye and ocean-type chinook, are doing "generally doing well" and are not exhibiting long-term declines.
According to the report, chinook, sockeye and coho numbers are declining throughout the province. Warming ocean temperatures enable less-nutritious zooplankton — a key food source for salmon — from southern latitudes to thrive in warmer northern waters.
To learn about salmon and their importance for the survival of the southern resident killer whales check out the CBC podcast Killers: J pod on the Brink.