We don't know exactly what's happening to our returning salmon this year.
So how can we know for sure what will happen to the salmon 50 years from now?
We can't, of course. That's why we have to insist on aggressive salmon recovery -- and now. We can't settle for half-measures or take comfort in short-term population increases or numbers that falsely suggest the fish are saved.
The science surrounding salmon is imprecise, their fate uncertain. Let's look at history and science -- and contemplate the future.
As the nation pulled out of the Great Depression, the federal government launched into the dam-building era on the Columbia and lower Snake rivers.
Bonneville Dam was completed in 1938, spanning the Columbia upstream from Portland. Over the next 37 years, seven more dams would follow.
During the spring of 1938, 22,967 spring chinook passed through Bonneville Dam. That number pales in comparison to the remarkable 2001 spring chinook run of 391,842 fish, or even the just-completed spring chinook run at Bonneville, totaling 75,164 fish.
It's tempting to draw snap comparisons between 1938 and today. It's misleading, however.
First, the 2001 and 2005 salmon numbers are inflated by hatchery-raised fish. A rough rule of thumb on the current chinook numbers is 80 percent hatchery fish to 20 percent wild fish, says Bert Bowler, native fisheries director for Idaho Rivers United.
Second, consider that in 1938, a thriving canning industry caught spring chinook in the Columbia before they could ever reach Bonneville. The industry probably harvested more than half of the returning chinook, said Jim Lichatowich, a retired fisheries biologist based in Columbia City, Ore.
Put these two factors together, and the wild chinook class of 2005 is probably down considerably from 1938.
So many variables affect salmon swimming to the Pacific and returning to Idaho. These variables worked in favor of the 2001 chinook runs.
Most of the fish had migrated to the Pacific in 1999, a good water year. Good ocean conditions awaited the young fish. Temperatures were cool. Predators were relatively scarce; food was abundant.
In 2001, the salmon came back to fresh water with a flourish.
Never before, nor since, have as many chinook passed through Lower Granite Dam, the 30-year-old dam that poses the final obstacle to Snake River chinook. Small Idaho towns profited from a fishing season worth close to $90 million -- offering a fleeting glimpse at what a robust chinook fishery offers.
"One or two or three good years do not make a trend," Lichatowich said.
Which brings us to this year.
This figured to be another big year for Idaho chinook. After all, the returning fish are the offspring of the 2001 run. And the 2004 numbers for "jack" chinook -- 3-year-old fish that return after just one year at sea -- were well above the 10-year average.
Yet this year's returns are down significantly -- and inexplicably. The Idaho Department of Fish and Game has responded by cutting back the salmon season.
There is some danger in reading too much into one bad year, just as in reading too much into one good year. But it's important to remember that saving rare species is by definition a conservative process -- helping them through bad years to avoid extinction. It's vital the people of the Pacific Northwest hold their federal agencies and elected leaders to the mandate of the Endangered Species Act: species recovery.
2006 -- and beyond
Predicting the future for salmon is difficult. How will salmon manage as population growth places more pressure on the region's water? Or if the climate grows warmer in the years ahead? The region can't assume the salmon will live in an unchanging river system, said Christine Moffitt, a U.S. Geological Survey employee who teaches at the University of Idaho's College of Natural Resources.
And federal agencies and elected officials need to consider one other huge unknown: How long can our salmon continue to struggle while we argue over how to save them?
If we ever get that answer, it would come too late to save the fish. "The only way we're going to find that out is to break the bank," Lichatowich said.
Snake River salmon are fragile yet resilient. They remain rare after more than a decade on the endangered species list.
They also are hardy enough to have survived since the Ice Age. To give salmon a chance to survive another 10,000 years, we must realize that it will take more than a couple of good years to bring them back.
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