Yearly fluctuations don't concern biologists

By Alex Breitler, Record Searchlight
February 10, 2005

It doesn't seem like a fitting end for the "king fish."

Hefty chinook salmon float in the Sacramento River, their carcasses bloated and anything but dignified.

These are the same fish that beat the odds, swimming all the way to the ocean and escaping predators and fishermen's nets before fighting their way back upstream to spawn.

Now they're dead and rotting in the river. Not a glorious way to go.

But in death, these fish serve one more critical purpose. State biologists are able to estimate each year's salmon run populations in part by counting their bodies.

The results are used to discern trends, set fishing limits or quotas and evaluate hotly debated water-management policies.

Preliminary figures estimate 352,535 fall-run chinook spawned in the Sacramento River system last year, down from a record high two years ago and the lowest total since 1998.

Still, the salmon run was a healthy one compared with the 1980s and early 1990s.

Many of the fish that spawned this year in the Sacramento and its tributaries hatched three years ago in the same waters before heading to the ocean. So comparing the numbers on a year-to-year basis doesn't give a true picture, said Department of Fish and Game fisheries biologist Randy Benthin.

"This is an inexact science," he said. "But we want to be as accurate as we can."

The numbers show that tributaries like Clear Creek are particularly important for salmon.

About 193,000 fall-run fish spawned in tributaries last year, compared with just 43,600 in the river itself. Another 116,000 came from hatcheries.

More than 140,000 chinook salmon made it past the Red Bluff Diversion Dam, spawning somewhere between there and Keswick Dam, which blocks historic habitat upstream.

Hundreds of thousands of fish may sound like a lot, but each female chinook can carry 3,000 to 5,000 eggs.

Only a few will survive long enough to replenish the population in three years' time.

The dangers are many. Sometimes the salmon run takes a hit if there's not enough water released in the spring to flush juvenile fish downstream through the delta, Benthin said.

Even with plenty of water, the juveniles must avoid getting gobbled up by critters.

Once they reach the ocean, they need favorable currents to lift nutrients off the bottom. At the same time, they must evade the nets of commercial fishermen.

Finally, they tackle the long journey upstream, imperiled this time by recreational fishermen. "It's a challenge," Benthin said.

But all it takes is two surviving fish to give life to thousands more.

While officials called last year's Sacramento run "decent," better news still is that winter-run salmon, which dwindled as low as 186 fish in 1994, have risen to between 7,400 and 8,800 the past four years.

"They are definitely coming back from the brink of extinction," said associate fisheries biologist Doug Killam of Red Bluff.

The concern is with the Klamath system, where some fear the next fall run will be smaller because of a fish kill that took a chunk out of the previous generation in 2002.

Just shy of 89,000 fall-run chinook salmon returned to the Klamath and Trinity rivers last year, said Wade Sinnen of Fish and Game's Arcata office. The average is about 126,000 fish.

"This was a poor year," Sinnen said. "We're probably going to have pretty conservative limits."

Besides counting carcasses, officials also trap fish, study their nests and conduct snorkel surveys to estimate their populations.

Zeke Grader of the Pacific Coast Federation of Fishermen's Associations attributed the fall-run's abundance in recent years -- and its decline in 2004 -- to changing ocean conditions. "There's hardly any concern," he said.

Reporter Alex Breitler can be reached at 225-8344 or at abreitler@redding.com.