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More sockeye return to Redfish than in years past, IDFG says

by Thomas Plank
| August 13, 2020 1:00 AM

As of Monday, 16 sockeye salmon had made it back to Redfish Lake in central Idaho.

The iconic Pacific salmon species has started its return to Redfish Lake this season after a record-low 17 sockeye salmon made their way back to Idaho in 2019.

The returning salmon — Redfish Lake is named for them — are part of an ancient cycle that has been disrupted by human activity on waterways across the Northwest. This year should see better return rates than last year, according to Idaho Department of Fish and Game.

So far in 2020, 412 sockeye have passed the Lower Granite Lake Dam on the Snake River in southeastern Washington. Those fish are working their way up the river into Idaho, where they will eventually be trapped by IDFG and transported to the Eagle fish hatchery, where genetic testing will determine if they will be incorporated into the captive broodstock that has kept sockeye salmon populations alive in Idaho.

In the late 1800s, between 25,000 and 30,000 sockeye salmon returned to the Stanley Basin. Naturally produced sockeye salmon migrate from the Sawtooth Valley lakes in the late spring along with hatchery reared smolts which are released in early May to Redfish Lake Creek, Dan Baker and John Powell of Fish and Game said. Snake River sockeye salmon spend one to three years with a majority of the sockeye salmon returning after two years in the ocean before returning to the Sawtooth Valley. Unlike other salmon, Snake River sockeye spawn and rear in lakes.

There are two sockeye breeding programs that maintain captive breeding populations of salmon: IDFG’s Eagle Fish Hatchery and the National Oceanic and Atmospheric Administration Fisheries’ Burley Creek hatchery.

“Even if no adult sockeye salmon returned from the ocean the Redfish Lake sockeye salmon population would continue to persist through the efforts of this program. A year with no returning sockeye is obviously the worst-case scenario, and will hopefully never come to pass,” Baker and Powell said.

Idaho Conservation League spokesman Scott Ki said while the higher numbers of returning sockeye in 2020 was encouraging news, the fish still face considerable obstacles before they can flourish.

“Factors that keep wild salmon from returning include warm water and ocean conditions, predators, degraded habitat, commercial and sport fishing (harvests), hatchery fish and dams (hydropower),” Ki wrote in an email.

Despite the 400 sockeye salmon that have passed the Lower Granite Lake Dam on their way to Redfish Lake to spawn, that number of fish is still far below the minimum population to delist the species from the Endangered Species List or to recover, Ki said.

“You’d need at least 40,000 sockeye adults to return in order to restore abundant, harvestable stocks to Idaho,” Ki said. “Four hundred is … far from being enough.”

According to IDFG experts, there are a few population benchmarks that could delist the Sawtooth Valley sockeye salmon. One is a 10-year average natural-return of 1,000 sockeye to Redfish Lake, 1,000 to Alturas Lake and 500 to Pettit Lake. From 2010-2019, the annual sockeye return to the Sawtooth Basin has averaged 558 fish in total.

“The current goal of the recovery program is to return enough anadromous adults from our hatchery releases to recolonize the natal habitat in the Sawtooth Valley lakes and increase natural production,” Powell and Baker wrote.