Tests last year at three federal dams on the Columbia River demonstrated marked improvements in the safe passage of juvenile fish, one of several achievements described in a new report released today on federal actions to protect Columbia and Snake River fish.
The report details 2011 progress under NOAA Fisheries' biological opinion for the operation of the federal dams to protect salmon and steelhead that are listed under the Endangered Species Act. Under the biological opinion, the U.S. Army Corps of Engineers, the Bonneville Power Administration and the Bureau of Reclamation - collectively known as the Action Agencies - are taking actions to protect salmon and steelhead survival at all phases of their lifecycle. These include providing safe fish passage through the hydrosystem, making habitat and hatchery improvements and also improving harvest and predation management.
"We are seeing improved dam survival for juvenile fish as a result of our hydro actions," said David Ponganis, programs director, Northwestern Division of the U.S. Army Corps of Engineers.
Those results are due to improvements such as spillway weirs that help fish past the dams more quickly and a spillwall at The Dalles Dam that safely routes fish into a deeper part of the channel below the dam, where they are better protected from predators. At The Dalles Dam in 2011, testing showed that 99 percent of juvenile steelhead and 96 percent of juvenile spring chinook passed safely in 2011. This was the second year of testing at The Dalles Dam with positive results.
Under the biological opinion, the Action Agencies spill water at the eight federal dams on the Snake and Columbia Rivers from early April through August, routing more fish over the dam rather than through turbines.
The report also documents that in 2011, more than 1.5 million adult salmon and steelhead returned to Bonneville Dam on their way back to the spawning grounds. This was the fourth highest number of returning fish since counts began in 1938 and another sign that recovery efforts are working.
"We have a comprehensive plan that is helping salmon in the tributaries, the estuary and at the dams," said Steve Wright, the administrator for BPA. "And, it is thanks to the hard work of our many partners throughout the Columbia River Basin - the tribes and states that are working together with the federal agencies. Together, we have achieved great results."
The Action Agencies and their partners made substantial improvements for salmon spawning and rearing habitat in the tributaries of the Columbia and Snake as well as in the estuary in 2011. They secured 25,700 acre-feet of water through irrigation efficiencies and water transactions, in streams that often went dry in the summer. They improved or opened access to more than 280 miles of spawning and rearing habitat through removing irrigation diversions and other barriers.
In the estuary, the agencies improved and restored 6.6 acres of streams and channels and removed tide gates and modified dikes to open up a total of 126 acres of historic tide channels. Research has consistently shown that juvenile salmon begin using restored estuary habitats almost immediately after these floodplain habitats and wetlands are reconnected.
The report also notes some areas for improvement. Avian and sea lion predation continues to be a serious issue for the survival of salmon and steelhead. In 2011, the Corps constructed and improved an avian deterrent wire array over the tailrace at The Dalles Dam and reduced habitat for predatory Caspian tern nesting on East Sand Island. Sport anglers removed approximately 155,000 pikeminnow from the Columbia last year. The sport reward program has reduced pikeminnow predation on juvenile salmon by roughly 40 percent since 1990. The Action Agencies continue to focus on controlling predation by native and non-native species.
The full 2011 Progress Report and other background material are available at: www.salmonrecovery.gov.