Sunday, November 8, 2009

WEIR NEEDED ON JOHN DAY RIVER

The high stray rate of barge transported steelhead, primarily form Snake River hatcheries, are a growing threat to wild John Day River steelhead. There is no hatchery program on this river, but the strays have fixed that with 29-41% of adult steelhead found throughout the John Day Basin are of hatchery origin. The Mid-Columbia Steelhead Recovery Plan notes this problem on the John Day and Deschutes Rivers. The ODFW and NFS have begun to place weirs on tributaries of the Deschutes River in order to excluding hatchery fish from spawning naturally with wild steelhead. A similar program is needed for the John Day River. The steelhead are listed as threatened and the state manages it as a wild salmon and steelhead reserve. The stray, barged hatchery steelhead are a threat to wild steelhead and to their recovery under the ESA. Bakke


John Day River Steelhead: In Through the Out Door

Tim Unterwegner and Jim Ruzycki - Oregon Department of Fish and Wildlife,
John Day, OR
2008 Pacific Coast Steelhead Meeting
March 4-6, 2008

The John Day River is one of the longest free flowing rivers in the lower 48 states and is managed exclusively for wild anadromous fish production. Although no releases of hatchery fish occur in the basin, recent evidence suggests a relatively high percentage of returning adult steelhead are of hatchery origin. Detections in the migration corridor also suggest that John Day fish stray afrom their natal watershed. We began tagging wild juvenile steelhead in 2001 with Passive Integrated Transponder (PIT) tags in an effort to determine smolt to adult survival (SAR) and track movement of juveniles and adults. Tracking was accomplished using the Columbia River PIT tag information system (PTAGIS). This system allows us to track the movement of tagged fish as they are detected at antennas throughout the Columbia River basin. To date, 13,910 wild juvenile steelhead have been tagged in the John Day River and 307 returning adults detected at Bonneville Dam, the lowermost dam on the Columbia River. In September 2007, a prototype antenna array was installed by Biomark Inc. on the John Day River, with the primary purpose of determining the incidence and origin of stray steelhead. SAR of John Day River steelhead to Bonneville Dam has varied from 1.4% to 2.9%. Observations from recent surveys in the basin indicate that 29–41% of adults throughout the basin are of hatchery origin. Greater than 50% of returning John Day origin steelhead pass over McNary Dam which is 74 miles upstream of the mouth of the John Day River. Hatchery steelhead straying into the John Day primarily originate from Snake River releases and so far, these stray fish were primarily transported as smolts in barges down the Snake and Columbia River corridors. Our evidence indicates clear exchange of steelhead among populations of the Columbia River basin.

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