Potentially Catastrophic Collapse of Sockeye Salmon Run

Scientists and conservationists are stunned by the unprecedented number of sockeye salmon lost to poor weather conditions, calling into effect commercial and recreational fishing restrictions in and around the Columbia River indefinitely.

An abundant sockeye return in 2010 allowed Fish and Game to try a pilot project where 19 sockeye were trapped and trucked from Lower Granite Dam to the Eagle Hatchery to see if the fish could survive the rigors of transport, and they did, said Roger Phillips, a Fish and Game public information specialist.

But the tribal alliance says only 5,000 to 15,000 sockeye have so far made it to Osoyoos Lake.

In fact, record numbers of sockeye salmon have been passing through the dam since 2012.

In the last decade, between 30 and 78 percent of sockeye that crossed Lower Granite Dam completed the trip to the Sawtooth Basin.

Only 18,000 sockeye are expected to return this year to spawning grounds in the rivers and streams in British Columbia’s South Okanagan region. Continuous above-average temperatures have raised the water temperature and created a thermal barrier, disabling the migration.

Columbia River sockeye salmon are facing serious threats to the already endangered species, as longer than usual hot spells along the river’s path through the Pacific Northwest are heating up the water. According to Ahrens, this is due to an increase in microscopic killers: “Bacteria, pathogens, and viruses get more and more effective at doing their jobs when the water gets warmer, and fish less so”.

“At any given year, maybe one in 10 fish will go through these physical stressors, but this year we’re seeing even higher rates – anywhere between 30 and 50 per cent of the fish are showing these signs”.

To help aid in their conservation, Oregon and Washington officials have both agreed to place a ban on commercial and recreational fishing indefinitely.

“We’re not expecting good survivals”, he said.