At a Monday press conference, freshwater researchers and resource management experts said consumers can expect "highly variable but generally reduced" returns on five species of salmon in British Columbia, including sockeye, pink, chinook, chum, and coho.
Exceptionally warm conditions partnered with extreme climate events like El Niño have compromised the salmon diet, they explained, by bringing smaller, less nutritious plankton into B.C. waters, along with migratory predators like shark and mackerel that feed on salmon young and old. These events have also resulted in lower river flows and higher water temperatures that affect salmon migration, survival, and spawning.
"Salmon have very complex life cycles," Ian Perry, a research scientist with DFO's Ocean Sciences Division, told reporters. "The ocean conditions that are important are not just last year's conditions, but in some cases, the ocean conditions three or four years ago. Over the past few years, we've had some very different and unusual conditions in the ocean."
Temperature anomalies are expected to continue, they said, bringing along with them salmon-attacking pathogens that thrive in warmer water.
While none of the panel was quite ready to use the words 'climate change' in relation to diminishing salmon stocks, it noted that between 2014 and 2015, the eastern subarctic Pacific experienced the warmest winter water temperatures ever observed. The scientists are particularly concerned about populations in the Fraser River, where the earliest peak freshwater flooding since 1912 was recently observed near Hope, B.C.
“What we are seeing is inter-annual variability," Perry explained. "What we are finding is that on average, the highs tend to be a bit higher and the low temperatures also tend to be a bit higher."
Many B.C. salmon hotspots will be closed to commercial fishing this year, said the panel, and in rare cases, only local First Nations fishing will be permitted.
DFO scientists Dr. Ian Perry and Dr. David Patterson spoke about the prospects for Pacific salmon in British Columbia after years of warmer temperatures and "unusual" conditions during a press conference in Vancouver on Mon. June 20, 2016. Photo by Elizabeth McSheffrey.
Their concern comes on the heels of a federal commitment to boost Atlantic salmon populations by advancing 61 recommendations in the Special Report on Wild Atlantic Salmon in Eastern Canadas ubmitted by the DFO Minister's Advisory Committee on Atlantic Salmon in July 2015. The initiative is supported by nearly $200 million in the federal budget allocated to ocean and freshwater science, a portion of which will be spent on hiring scientists and promoting partnerships for the long-term recovery of Atlantic salmon stock.