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Only Three Sockeye Return to Idaho's Sawtooth Valley by Bill Rudolph NW Fishletter, November 10, 2003

Most wild and hatchery salmon runs have improved rapidly in recent times, thanks largely to improved ocean conditions. But there is still one big exception: the Idaho sockeye run.

Only three descendants of the original Lonesome Larry returned to Idaho's Sawtooth Valley this year, home of the Redfish Lake sockeye, the first Northwest salmon stock listed for protection under the Endangered Species Act in 1991. Twelve sockeye were counted at Lower Granite Dam by the end of August, but that last 450 miles to the Lake must have been too much for them.

Lonesome Larry was the lone sockeye that returned in 1992. His precious bodily fluids were frozen as part of a captive broodstock program that started in 1991, a last-ditch effort aimed at saving the run from extinction.

Idaho Fish and Game biologist Paul Kline said 30 adult fish were expected from the 30,000 smolts that emigrated in 2001. He did not speculate on the cause of the poor return.

All sockeye returning to Idaho since 1997 are products of an intense captive broodstock program. In 2002, 22 adult sockeye returned, while 26 of them showed up in the valley in 2001.

In 2000, biologists were shocked when nearly 260 sockeye returned from an out-migration of 38,000 smolts raised in the program, along with an unknown number of out-migrants resulting from the planting of nearly 150,000 pre-smolts in Redfish, Pettit and Alturas lakes.

This year's low numbers may have something to do with the poor migrating conditions for fish in the drought year 2001, when extremely low flows plagued the Columbia Basin, a dire situation compounded by the distances these fish had to cover. The Redfish Lake run is the southernmost sockeye stock on the West Coast, migrating farther and spawning at a higher altitude than any other. They swim almost 900 miles to reach the ocean, and another 900 miles back.

But some critics of the ESA listing still say the fish shouldn't even be protected, because there is no real distinction between the 5,000 to 10,000 resident spawning kokanee in Redfish Lake and the ones who go to sea.

They point to the fact that a dam blocked access to Redfish Lake for more than 20 years, and speculate that the fish migrating now are simply descendants of the freshwater residents with "a sporadic seaward drift."

However, another hypothesis speculates that operators of the dam in question may have occasionally helped fish get into the lake, which could have kept the stock from going extinct.

When the stock was originally listed under the ESA in 1991, only the sea-going component was protected. At the time, National Marine Fisheries Service scientists admitted they did not have enough information to make a satisfactory decision about whether the two components were different stocks.

Genetic analyses found that returning adults and out-migrants "were similar but distinct" from the freshwater kokanee, but newer analyses that have examined growth in the fishes' earbones found that many out-migrants have had a resident female parent.

Further investigation has found a small number of kokanee spawning about the same time and place as the sockeye. Most kokanee spawn up a local creek, while the sockeye spawn along a beach at Redfish Lake.

"NMFS will never make a judgment that will make kokanee part of the ESU [evolutionarily significant unit]," said hatchery expert and retired University of Idaho professor Ernie Brannon, who also studied Redfish Lake sockeye. "They have too much at stake."

Brannon said it would be better to simply determine if the kokanee population is viable, since it's likely that at intermittent intervals some of them leave the lake for the ocean. This likelihood was also suggested by Idaho consultant Don Chapman in a 1990 sockeye study commissioned by The Pacific Northwest Utilities Conference Committee.

"Scientists should be studying the environmental factors that encourage the fish to migrate," Brannon said.

But the federal scientists' latest assessment of the sockeye stock has maintained the basic difference between the ocean-going and kokanee components. Pointing out that only 16 naturally produced adults have returned since the stock was listed, the NOAA Fisheries biological review team voted unanimously last February to keep it in the "in danger of extinction" category.

Most sockeye stocks in Idaho were extirpated on purpose, poisoned by Idaho Fish and Game years ago to keep the fish from eating the trout prized by sports fishermen. But Alturas and Redfish lakes were too deep for the poison to be used effectively, so the fish got a reprieve, said Rob Dillinger, a Portland-based consultant who worked for IDFG in the early 1990s.

Dillinger also said an effort to boost the lake's productivity failed when test corrals filled with fertilizer encouraged the growth of a type of plankton that fish wouldn't eat. It crowded out the plankton the fish preferred and the test fish starved.

"It's a murky, murky situation," Dillinger said. He thinks it is likely that some kokanee go to sea if given the chance. But he pointed out that the lineage of the present run may have been derived from "residual" fish that remain in fresh water while most go to sea, traits also evident in Lake Wenatchee's sockeye population.

The National Research Council also noted in its 1993 salmon study Upstream that the Redfish Lake run may have been made up of residual sockeye.

The Lake Wenatchee run is relatively healthy compared to Redfish Lake's. The Wenatchee fish swim hundreds of miles less, but more than 100,000 sockeye returned to the mid-Columbia in 2001. And this year, about 35,000 made it past Rock Island Dam on their way home.

Chuck Peven of Chelan PUD said the wild component of the 2001 Lake Wenatchee sockeye run had a smolt-to-adult return (SAR) rate of 2.1 percent, with hatchery fish displaying a return rate of 0.7 percent. The Redfish Lake return of 26 fish in 2001 showed a SAR of .05 percent to 0.14 percent.

In September, IDFG released 30 adult hatchery-raised sockeye into Redfish Lake to help maintain the run. Over 300 hatchery adults have been added over the past few years. Many have been raised in Washington state, at NOAA Fisheries' Manchester lab on Hood Canal.

NOAA Fisheries announced interim recovery targets for listed stocks more than a year ago, suggesting that 1,000 sockeye returning to one lake and 500 returning to another lake in the Sawtooth Valley would be an adequate productivity goal.

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