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.
Though the Okanagan sockeye were never listed as an Endangered Species, as Snake River sockeye in Idaho were, the future was not looking bright for Okanagan sockeye in the late 1980s and early 1990s, said Joe Peone, fish and wildlife director for the Confederated Tribes of the Colville Indian Reservation, which is in the Okanagan Basin.
Fewer than 9,000 sockeye returned to the Columbia Basin in 1995.
The operation of hydroelectric dams regularly washed out the eggs after the fish laid them in the river, or left them high and dry before they hatched. Sockeye proved difficult to rear in hatcheries, so tribes on both sides of the border teamed up with local utilities that owned the dams to work out rules for maintaining flows that the fish could live with. Natural meanders were restored to rivers that had been straightened to reduce flooding.
“Right now those fish are utilizing maybe a quarter of their historic habitat,” Peone said. If more habitat is restored, “You could see 1 million fish coming back here.”
Ritchie Graves, a NOAA Fisheries Service biologist who makes sure federally owned dams are living up to their Endangered Species Act obligations not to kill too many salmon, said the survival rate for young salmon swimming downstream to the ocean has been higher than ever the past three years, hitting about 50 percent for sockeye.
Those improved dam operations have also benefited chinook, coho, chums, pinks and steelhead, said Graves. The six species combined accounted for 1.8 million salmon over Bonneville in 2010, compared to 471,144 in 1938.
Once young salmon get to the ocean, scientists have only a vague idea where they go, and an incomplete understanding of why some years they thrive and some years they starve. Generally, years when climate and weather cause the ocean waters to well up, salting the water column with food, fish do better. But unlike most salmon, which eat other fish, sockeye eat plankton, tiny shrimplike animals.
Though poor ocean conditions have been blamed for a nosedive in chinook salmon in Alaska this year, sockeye have done well, not only in the Columbia, but in Canadian and Alaskan rivers as well.
“Whatever is going on in the ocean is basically being good to sockeye,” said Tweit.
More Related Stories
- Mississippi could begin prosecuting women for miscarriages
- Teenage girl claims she was beaten up for looking like Taylor Swift
- UK Military: London attack victim was a "model soldier"
- Billionaire hedge funder: Babies, breast-feeding "kill" focus, keep women from succeeding
- "Bookless library" set to open in Texas
- 2 more arrested in London attacks
- Glenn Beck: CNN interview with atheist tornado survivor was a setup!
- Incoming BBC news director on journalism gender gap: "We can do better"
- Illegal construction, shoddy materials at fault in Bangladesh factory disaster
- Ahead of Obama's speech, U.S. acknowledges four American drone killings
- Must-see morning clip: Bill O'Reilly visits "The Daily Show"
- Lawsuit alleges anti-gay hiring practices at ExxonMobil
- Boy Scouts poised to vote, still greatly divided on gay youth
- House supporters of KXL received $56m from fossil fuel industry
- 80-year-old becomes oldest to climb Mount Everest
- Before FBI shooting man implicated self, Tsarnaev in triple murder
- Paul McCartney backs Pussy Riot
- UK emergency committee convenes after attack
- Brave scout leader tried to reason with London attackers
- If Alex Pareene were a cable news executive...
- El Salvador court delays ruling on abortion case while woman's life hangs in the balance
Featured Slide Shows
The week in 10 picsclose X
- 1 of 11
Lisa Montgomery embraces her nephew Thursday after a tornado tore apart her home in Cleburne, Texas. The twister killed six people and destroyed entire swaths of the North Texas town.
Credit: AP/LM Otero
Jack McMahon, the defense attorney for abortion doctor Kermit Gosnell, speaks outside the Criminal Justice Center in Philadelphia Tuesday. His client was convicted of killing three babies in his clinic, and will serve multiple life sentences.
Credit: AP/Matt Rourke
A photo taken Monday captures Vice President Joe Biden's response to a Milwaukee second-grader's innovative proposal to end America's epidemic of gun violence. This guy!
Credit: AP/Jenny Aicher
Sen. Rand Paul, R-Ky., flanked by a grouper-eyed Michele Bachmann, addresses the IRS' admission that it targeted Tea Party groups in advance of the 2012 election. In an op-ed for CNN Thursday, the Kentucky senator slammed the president for his faux outrage.
Credit: AP/Molly Riley
Ousted IRS chief Steven Miller is sworn in on Capitol Hill Friday. Miller testified before the House Ways and Means Committee on the extra scrutiny the agency gave conservative groups applying for tax-exempt status.
Credit: AP/J. Scott Applewhite
Attorney General Eric Holder pauses as he testifies on Capitol Hill before the House Judiciary Committee Wednesday. Holder is under fire, among other things, for the Justice Department's gathering of phone records at the Associated Press.
Credit: AP/Carolyn Kaster
O.J. Simpson sits during an evidentiary hearing at Clark County District Court in Las Vegas, Nev., Thursday. Simpson, who is currently serving a nine-to-33-year sentence in state prison for armed robbery and kidnapping, is using a writ of habeas corpus to seek a new trial.
Credit: AP/Las Vegas Review-Journal/Jeff Scheid
Major Tom to ground control: On Sunday astronaut Chris Hadfield recorded the first music video from space, a cover of David Bowie's "Space Oddity."
Credit: AP/NASA/Chris Hadfield
When it rains it pours. President Barack Obama speaks during a news conference Thursday with Turkish Prime Minister Recep Tayyip Erdogan, inexplicably inspiring an #umbrellagate Twitter meme.
Credit: AP/Jacquelyn Martin
A smoke plume rises high above a road block at the intersection of County A and Ross Road east of Solon Springs, Wis., Tuesday. No injuries were reported, but the the wildfire caused evacuations across northwestern Wisconsin.
Credit: AP/The Duluth News-Tribune/Clint Austin
Recent Slide Shows
- 1 of 11