[an error occurred while processing this directive]

  Back to Columbia River Home
Image Gallery
Page 1Page 2


  Salmon   Salmon
After several years at sea, Pacific salmon are seized by a biological imperative to return to the streams of their birth. Following olfactory clues, Columbia River salmon, which travel as far north as Alaska, struggle upstream to spawn, then die.

Their offspring will spend up to two years in fresh water, then follow their instincts down the Columbia and out to sea—and the cycle swims on. Or so it once was.

Salmon face a daunting array of obstacles on the river. Farming and logging bury spawning beds with runoff. Irrigation diverts water from the spawning streams. And the 14 dams on the Columbia’s main stem stand in their way.

On the way out to sea, many smolts are killed by high water pressure while passing through dams. On the way back, adults may be left too exhausted from climbing fish ladders (wide concrete waterways that guide fish over dams) to spawn at all, say some conservationists—and some dams have no fish ladders at all.

Today 200,000 to 300,000 wild salmon ply the Columbia, down from 10 million to 16 million in the early 1800s. To ensure their survival, fishers and conservationists advocate improving fish ladders; controlling development, farming, and logging; further tightening fishing restrictions; and even dismantling dams.

  Northern squawfish   Northern squawfish
Other than humans, these are perhaps the salmon’s most formidable foes on the river.

Native to the Columbia, squawfish seem to have taken the taming of the river in stride. Unlike salmon, they thrive in the slow-moving, warmer water created by damming, as do the non-native smallmouth bass and walleye. There’s something else they’ve all got in common: a taste for juvenile salmon.

The Bonneville Power Administration, the U.S. agency that wholesales power generated by federal dams in the Columbia River Basin, has estimated that in one reservoir alone these three species consume 2.7 million juvenile salmonids (salmon and steelhead trout) annually. Squawfish took the lion’s share—an estimated 78 percent.

Against these predators, salmon hardly have a fighting chance. By the time they face squawfish, they may already be stressed or injured by dam passages and are almost certainly out of their element—the cool, coursing waters to which they are adapted.

  Caspian terns   Caspian terns
With shoreside islands as their airbases, these sky divers raid the river for crustaceans and small fish, though they’ve been known to nosh on insects too.

Dredging on the lower Columbia by the U.S. Army Corps of Engineers has left behind oversize sand piles. As these artificial islands have grown, so have tern numbers; the islands are just the sorts of spots where these gregarious birds gather in small colonies. But as the area grows more welcoming to terns, it becomes that much less hospitable to salmon.

Relatives of gulls, terns are so successful at snatching smolts, or juvenile salmon, that the National Marine Fisheries Service and the Fish and Wildlife Service have cited Caspian terns as a significant factor in salmon decline on the Columbia.


  Historical overfishing   Historical overfishing
As current threats to Columbia salmon go, commercial fishing is fairly toothless. For one thing, the industry is heavily regulated on the river. For another, there just aren’t that many salmon left to catch here. But it wasn’t always so.

Almost two centuries ago Lewis and Clark witnessed a Columbia “crowded with salmon”—an estimated 10 million to 16 million swimming upstream each year. Later in the 1800s, when white settlers came to the Columbia, many followed the local Indians’ example and made a life from the fish. Then they made an industry.

Canneries came to the lower Columbia in 1866, and commercial fishing exploded. The late 1800s saw record annual catches of as much as 43 million pounds (20 million kilograms) of salmon and steelhead trout, and an alarmed United States’ top fisheries official warned that overfishing would destroy the Columbia’s salmon runs.

By the 1930s the yearly salmon and steelhead catch had been fished down to 25 million pounds (11 million kilograms). Now, thanks at least in part to the dams, that number has shriveled to around one or two million pounds (450,000 or 900,000 kilograms), while the number of canneries on the lower Columbia has gone from two dozen, in the early 1900s, to three today.

Once the mighty exterminator, the Columbia fishing industry has been, like its prey, relegated to the ranks of the endangered.

  Farming   Farming
They’re the same steel boxes seen piggybacking on ships around the world. But they conceal a curious bounty: potatoes, onions, corn, carrots, and grain grown in the naturally barren Columbia Plateau.

East of the Cascade Range, the Columbia winds across the vast, parched plateau. There, not coincidentally, you’ll find 10 of the river’s 14 dams, their reservoirs fueling a herculean irrigation effort.

As the largest dam on the Columbia, Grand Coulee alone enables farming on 640,000 acres (258,994 hectares) via its reservoir, 27-mile-long (44-kilometer-long) Banks Lake. But the cornucopia comes at a price.

Runoff from streamside farms can smother gravel beds where salmon reproduce, and beds can become desiccated as water is rechanneled for agriculture. And humans aren’t immune either.

Though the Columbia reservoirs flooded ancestral homes, fishing spots, and hunting grounds of Native Americans, none of the water was allocated for their benefit.

      Page 1Page 2
Back to top

  Resources & Links | Credits
Virtual World: Columbia River National Geographic EarthPulse Sponsored in part by BP