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Fish Tales

Salmon migration numbers raise hopes

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If you think your life is tough, try being an Idaho sockeye salmon.

First, your species is so endangered that humans have to perform continual genetic testing to make sure there's not too much inbreeding. Then, there's a good chance you were at least hatched, if not raised, in a hatchery.

Once you make it to the lake, you have to swim more than 900 miles to the ocean, where you will face both predators and fishermen while you mature. Then, you have to come all the way back, swimming higher and farther than any other sockeye salmon, dodging dams, birds and bears just to get back to the lake where you started, only to spawn and die.

The good news is that all along the way, there are some humans trying to help.

Since sockeye salmon were first added to the Endangered Species List in 1991, wildlife managers have been working to increase the number of salmon returning to home waters with a variety of programs spanning every stage of the fishes' lives.

Managers still face an uphill battle toward full species recovery, but the amount of returning sockeye this year is an encouraging sign.

As of Aug. 27, 545 adult sockeye have made it back to the Stanley Basin—197 at the Sawtooth Fish Hatchery on the Main Salmon River and 348 at Red Fish Lake Creek—compared to just four in 2007, according to the Idaho Department of Fish and Game.

While it's not a record, Peter Hassemer, anadromous fish manager for IDFG, said this year's fish run is higher than has been recorded since the 1990s.

"It's a definite improvement," he said in a measured assessment of the situation.

The numbers of returning chinook salmon are up slightly as well, although Hassemer said they are far from where the department would like to see them. The amount of steelhead salmon has held steady over the last three years, although the number of wild steelhead is still down. Returning fish numbers can fluctuate widely from year to year, depending on the conditions each batch of young salmon face, and this year's large figure can't be attributed to any one factor.

Fisheries managers have been slowly increasing the number of hatchery fish released each year, either as eggs, smolts or adults. Most of the adult fish returning this year were hatched in 2004 and migrated to the ocean in 2006.

During their lifespan, both river and ocean conditions were better than usual, adding to the increased survival rate, Hassemer said.

"It's hard to pinpoint the relative contributions of each [factor]," he said. "When the stars align right, we see changes in the fish population."

But beyond what's happening naturally, wildlife managers across the Pacific Northwest have implemented numerous programs designed to both improve fish habitat and increase the likelihood of survival.

Across the Lemhi Basin, crews are working to reconnect smaller tributaries that have either become disconnected from the larger river system or allowed to go dry because of land use.

"We're going back into the system and looking at where we can make improvements that can benefit fish without disrupting other uses," Hassemer said.

Additionally, crews are strategically placing logs in the Potlatch River to provide much needed cover for fish making their way along the river. Work on the Columbia and Snake river system is a little more large-scale.

Many people point to the massive dams along the rivers as one of the biggest hurdles salmon of all varieties face in their migration. For years, environmental groups have proposed either breaching many of the dams along the river or increasing water flows during key points of fish migration. While only a few smaller dams have met their demise, wildlife and dam managers started retrofitting many of the older dams with new technology designed to help the fish more easily pass over the dams, while spilling less water.

Hassemer said those programs are still being evaluated, but he believes there are benefits to the fish population.

Increased stream flows have been used to help fish get down river quickly, and wildlife agencies also have used barges to move the fish to the ocean. But recovery programs aren't just limited to helping fish survive long enough to return to Idaho; wildlife managers are also looking at what happens after they die.

IDFG is following the lead of Oregon and Washington in studying the impacts of salmon carcasses on the environment. After fish spawn and die, their decomposing bodies provide a flush of nutrients to the ecosystem, but as salmon have been cut off from some of their historic spawning beds, the river environment has suffered.

Those now cut-off river systems include the Boise, Payette and Weiser rivers, which haven't been home to salmon in decades. For the first time in Idaho, IDFG officials are testing to see if reintroducing the nutrients the carcasses provide can reinvigorate the rivers.

"It can't be underestimated what these nutrients were doing to the system," said Gregg Servheen, wildlife program coordinator.

Servheen is leading the program which is testing those effects on nine streams and rivers in Idaho. Actual salmon carcasses were placed in three rivers, while workers used a manufactured pellet packed with the same materials found in salmon on three other streams. The remaining three are being left untreated to serve as a control group.

Servheen called migrating salmon "self-propelled fertilizer bags" for the river ecosystems.

"What you have is a small fish—4 inches—that leaves the system and three years later comes back as a 20-pound fish. Those 20 pounds were taken from the ocean and brought back here," he said.

Similar programs in Washington and Oregon have shown some initial benefits in a variety of ways. Dead salmon on a river bank lead to larger and more plentiful insects, which in turn provide more food for trout, which then grow bigger. Trout also benefit from the flush of algae, which comes with the decomposing salmon.

The nutrients also help plant production, which is of particular importance in southwestern Idaho, where the environment can be rather sterile, Servheen said.

Wildlife officials are also studying the effect that animals scavenging the dead fish have on the surrounding area.

This is just the first of a multi-year project funded in part by the Bonneville Power Administration and Idaho Power. Servheen said he doesn't expect any immediate results, but depending on success, the program could be expanded.

Wildlife managers are also continuing efforts to bulk up the hatchery program by doing genetic tests on fish that make it back to Idaho in an effort to add diversity to the captive breeding program. The remaining fish are returned to the lake.

While managers won't say that this is a turning point for the species, or even which programs are helping the most, they are guardedly optimistic.

"It's encouraging that these fish have the ability to respond to the programs we're implementing. There's an opportunity to restore those populations. [It] tells us that we are doing some of the right things," Hassemer said.

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