Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2004 Annual Report.
- Columbia Basin Fish and Wildlife Authority, Portland, OR
The runoff volume for 2004 was below average throughout the Columbia Basin. At The Dalles the January-July runoff volume was 77% of average or 83.0 MAF. Grand Coulee, Hungry Horse, and Libby were below their Biological Opinion reservoir target elevations on April 10 at the beginning of the spring salmon migration season. All major storage reservoirs except Libby, Grand Coulee, Hungry Horse, Dworshak, and Brownlee were within a few feet of full by the end of June and early July. Overall, NOAA Biological Opinion seasonal flow targets were not met at any project for either spring or summer migrations of salmon and steelhead. Overall, spill was reduced in 2004. Implementation of Biological Opinion spill for fish passage measures was wrought with contention in 2004, particularly for summer spill which was finally the subject of litigation. The spring migration spill season began with debate among the fishery mangers and tribes and action agencies regarding spill at Bonneville Dam for the Spring Creek Hatchery release. The USFWS agreed to a spill test versus a corner collector operation to determine the best route for survival for these fish. The USFWS agreement includes no spill for early Spring Creek Hatchery releases for the next two years. Spring spill at Snake River transportation sites was eliminated after April 23, and transportation was maximized. The federal operators and regulators proposed to reduce Biological Opinion summer spill measures, while testing the impact of those reductions. This proposal was eventually rejected in challenges in the Federal Ninth Circuit Court. The Corps of Engineers reported that spill at Bonneville Dam in the 2002 to 2004 period was actually lower than reported due to a spill calibration error at the project. Because flows were low and spill levels were easily controlled few fish were observed with any signs of Gas Bubble Trauma. The annual Smolt Monitoring Program was implemented and provided in-season timing and passage characteristics for management purposes and also travel time and survival analyses. These analyses showed consistent significant relationships between flow and spill percent versus survival for Steelhead in each reach analyzed. These results point to the importance of maintain high flows and spill for steelhead survival through the hydrosystem. A significant relation between either travel time or spill percent and survival for yearling Chinook was found. Given the high correlation between the variables it is not surprising that only one is retained in these models. Again the findings show the importance of flows and spill in spring Chinook survival through the hydrosystem. Survival trends in the Lower Snake River have been steadily declining for in-river migrants over the past several years with two notable exceptions. The lowest survivals were measured in 2001 when low flows and very little or no spill was provided led to poor migration conditions. Also survival increased in 2003 when Biological Opinion spill was provided despite moderate to low flows. Reach survivals in 2004 in the Snake River were the second lowest following 2001. Sub-yearling survival in the mid-Columbia in 2004 between Rock Island and McNary Dam were very low compared to other recent years. The general run-at-large migration timing of sub-yearling fall Chinook in the Snake River has changed with the increasing releases of hatchery supplementation production in the Snake River.
- Research Organization:
- Columbia Basin Fish and Wildlife Authority
- Sponsoring Organization:
- United States. Bonneville Power Administration.
- DOE Contract Number:
- 00004288
- OSTI ID:
- 861480
- Report Number(s):
- DOE/BP-00004288-3; R&D Project: 199403300; TRN: US200601%%869
- Country of Publication:
- United States
- Language:
- English
Similar Records
Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2002 Annual Report.
Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2003 Annual Report.
Related Subjects
BUBBLES
CALIBRATION
IMPLEMENTATION
INJURIES
LAWSUITS
MANAGEMENT
MONITORING
PRODUCTION
RUNOFF
SALMON
STORAGE
STREAMS
TARGETS
TESTING
US CORPS OF ENGINEERS
Fish Passage Center (Columbia Basin Fish and Wildlife Authority)
Fishways - Columbia River - Statistics
Salmon - Statistics