Tuesday, December 22, 2009

Juvenile Fish Transport System Working on the Upper Deschutes

photo by Dave Thurman

A massive project designed to give fish access to hundreds of miles of historic spawning habitat in the Upper Deschutes Basin appears to be working. Over the past few years Portland General Electric in cooperation with the Warm Springs Indian Tribe have been developing a trap an haul facility designed to get fish above Round Butte dam where they can access the upper Deschutes, Metolius, Crooked and numerous smaller tribs for spawning. Fish have been blocked from the upper river since 1968.

The most costly and technologically challenging part was a tower built to create an artificial current in Lake Billy Chinook which guides outmigrant fry into traps waiting for them at the dam facility. The fish are then hauled around a series of three dams and release them into the lower river. They're still fine tuning the operation of the smolt trapping facility however fish are already finding their way into the system, long before the bulk of the fry normally migrate. Fish this season are primarily from hatchery fry releases in the Metolius, Crooked and Whychus Creek. This past summer was the first time adults from the lower river were passed over the dam complex to spawn naturally so wild produced fish are still a year away from entering the system.

While technological fixes to problems like dams are rarely enough to restore wild populations, the early results from this project are encouraging. The project has the potential to open so much habitat for wild spawning fish, however it is unfortunate that they continue to plant hatchery fish in the Upper Deschutes watershed. Concerns over the spread of whirling disease have led some biologists to recommend not releasing hatchery fish. Furthermore continuing to release high numbers of hatchery fish will only lower the productivity of the wild spawners, slowing the ability fish to establish locally adapted populations.

Check out an article in the Columbia Basin Bulletin:

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