Steelhead may return above Applegate Dam
Scientists think fish released into Applegate Lake can get around dam, making reintroduction feasible
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Thousands of tiny winter steelhead finned their way from a stocking truck to the freedom of Carberry Creek on Monday, embarking on a journey that could help reclaim steelhead habitat believed lost forever 30 years ago with the building of Applegate Dam.
The fish are part of a state study to determine whether steelhead smolts released into Applegate Lake can find their way downstream through the dam, grow in the ocean and then return as adults up the Rogue River and into the Applegate, a main Rogue tributary.
If so, plans are to reintroduce winter steelhead upstream of this western Jackson County reservoir, tapping into 35 miles of suitable habitat ceded when the dam blocked steelhead access to the upper Applegate Basin in 1980.
"The habitat is there and the opportunity is there," says Dan VanDyke, the Oregon Department of Fish and Wildlife's Rogue District fish biologist. "I'd like to take advantage of that and get some more production up there."
Based on pre-dam studies, VanDyke estimates that the creeks feeding the reservoir could support as many as 850 spawning adult steelhead, which would be trapped at the dam and trucked to upstream spawning grounds.
Similar smolt releases into Carberry Creek the past two springs showed that at least a few of the fish survived and returned to the Rogue as immature "half-pounder" steelhead, ODFW reports show. "I'm excited about what we're seeing so far — that fish can get through the dam and survive," VanDyke says.
Biologists will look for evidence of returning fish from this year's batch through 2013, then decide whether enough adult steelhead return to move forward with the reintroduction.
The prospect of expanding steelhead spawning habitat in the 21st century enamors members of the Middle Rogue Steelhead Chapter of Trout Unlimited, whose members work with the ODFW on myriad fish-improvement projects throughout the Rogue Basin.
"That's right up our alley," says Bill Hickey, a chapter member in Grants Pass. "There's not much else you can do in that river now.
"We'd support anything that improves the run," Hickey says.
The project has its genesis in the planned $19 million hydropower retrofit of the dam by a private Utah firm called Symbiotics.
As part of its licensing through the Federal Energy Regulatory Commission, Symbiotics had to study whether any fish migrated out of the lake through the water-release tunnel at the dam's base.
Traps set immediately downstream of the dam's outflow tunnel in 2004-05 discovered that some of the rainbow trout, steelhead, chinook salmon and coho salmon stocked in the reservoir actually entered the water intake tower and migrated down to the river.
"That data really intrigued me and got me thinking about re-introduction above the lake," VanDyke says.
So the ODFW in April 2008 began a three-year study using some of the approximately 132,000 Applegate winter steelhead smolts raised at Cole Rivers Hatchery and released at the dam's base each spring as mitigation for lost spawning habitat caused by the dam.
Those smolts all have clipped adipose fins on their lower backs. But 40,000 of them now also have clips to a ventral fin on their lower bellies.
Half of them have clipped left ventral fins, noting they were released upstream of the dam. The remainder of the study fish have clipped right ventral fins and were released downstream of the dam.
As part of regular netting surveys done in late summer and fall on the lower Rogue, crews last year captured 20 of the right-finned steelhead released beneath the dam and another six steelhead among those released into Carberry Creek similar to those released Monday.
As part of Symbiotics' hydropower license granted in December, the company must install a $4 million fish screen to keep migrating fish out of the turbine it plans to install as part of the retrofit. That ensures that fish don't get killed by the spinning turbines.
The dam already has a fish trap installed at its base to collect returning adult steelhead for spawning at the hatchery. VanDyke says the plan would be to take some of those returning adults and truck them upstream of the dam and release them into the lake annually so they can find tributaries for spawning.
If done, the first crop of re-introduced steelhead likely would be returning adults among the smolts released upstream of the reservoir, VanDyke says.
The exact details have yet to be flushed out, VanDyke says.
"As soon as we're comfortable with survival rates and we can get sustainable production, I want to move forward," VanDyke says.
Reach reporter Mark Freeman at 776-4470, or e-mail at mfreeman@mailtribune.com.
