June 27, 2012 — Record numbers of a once-waning population of sockeye salmon have been returning to the Northwest's Columbia Basin this summer, with thousands more crossing the river's dams in a single day than the total numbers seen in some previous years.
Since Bonneville Dam outside Portland was built in 1938, there have been plenty of times there weren't 38,000 sockeye salmon swimming over the fish ladders in a whole year. But on Monday that many passed the Columbia River dam, and another 41,000 swam over the dam on Wednesday — a rate of nearly 30 a minute. That bought the total so far to 290,000.
A record run of more than 400,000 of the Columbia Basin's farthest-swimming salmon are expected to return this year, almost all of them wild fish bred in rivers, instead of the hatcheries that produce most Northwest salmon.
Sockeye cross nine dams to reach spawning grounds in northern Washington and Canada.
Biologists credit habitat improvements in the Okanagan Basin of northern Washington and Canada, improved dam operations, and favorable ocean conditions for the numbers. Okanagan sockeye swim more than 500 mils to spawn.
The bulk of the record returns are going back to the Okanagan River Basin, which drains a series of lakes straddling the Canadian border and flows into the Columbia.
"I have been telling people if they get the opportunity, to go up and visit the Okanagan," said Bill Tweit, special assistant to the director of the Washington Department of Fish and Wildlife. "It's going to be an incredible natural spectacle."
Smaller than most salmon at three to five pounds, sockeye are also the brightest in color. They are popularly known as bluebacks for their silvery blue hue as they pass Bonneville Dam, but as they get closer to laying their eggs in the gravels of rivers and lakes in the fall, their bodies turn bright red and their heads green.
Read the full story in the Boston Globe