fish passage

Developing fish passage and protection at hydropower dams

Source: 
ScienceDirect
Year: 
2006
Abstract: 

The development of waterways, for hydropower and other industrial uses, has substantially altered many of the freshwater habitats of the planet and this has had considerable impact upon aquatic organisms. Industrial changes in aquatic ecosystems, including hydropower development, can restrict or delay fish migration, increase predation, affect water quantity and quality, and subject fish to direct damage and stress. This review will focus on the consequences for fish welfare and the progress towards developing the means to pass and protect fish at hydropower dams, at water withdrawal facilities, and in other engineered aquatic environments. It primarily concerns the large mainstem hydropower dams in the Columbia-Snake River Basin in the northwestern United States. Some methods for improving fish passage and protection at hydropower damsinvolve modifications and additions to engineered structures and occasionally use sensory stimuli such as light, sound, turbulence, or electric fields to influence fish distributions. Measures to improve fish survival, like spilling water at a dam to provide non-turbine passage, can cause other problems for fish, for example higher dissolved gas concentrations downstream. Reducing losses of fish in industrial environments is desirable in both the industrialized world, where many fish-related problems currently exist, and in the developing world, here lessons already learned may make future development more cost-effective and benign.

Author(s): 

Carl R. Schilt

Contact: 

Environmental Research AssociatesP.O. Box 225North Bonneville, WA 98639

Notes: 

Cost Effective Recovery Strategies for Snake River Chinook Salmon

Year: 
2006
Abstract: 

Formulation of recovery plans for endangered salmon populations in the Columbia River Basin of North America is a complex, controversial resource-management issue. This report presents an integrated assessment model to analyze the biological-economic tradeoffs in recovery of Snake River spring/summer-run chinook salmon (Oncorhynchus tshawytscha).The authors find that the removal of an estuarine predator, the Caspian tern (Sterna caspia), and elimination of adult salmon harvest are recovery measures that markedly increase long-term population-growth rates regardless of transport effectiveness. Dam breaching significantly increases growth rates under the best available estimate of transport effectiveness. The authors also conclude that recovery strategies in the cost-effective set depend on assumptions about transport effectiveness. Tern removal and harvest elimination are generally cost effective. At the best estimate of transport effectiveness, strategies that discontinue smolt transportation or breach dams are prevalent in the cost-effective set. In contrast, strategies that maximize transportation are prevalent in the cost-effective set if transport effectiveness is relatively high. This paper links biology and economics through an integrated model thus providing a valuable tool for science-based policy and management.The paper can be downloaded from Michael R. Moore's website at http://sitemaker.umich.edu/micmoore/working_papers

Author(s): 

David L. Halsing and Michael R. Moore

Contact: 
Notes: 

Dam owners have to coddle fish

Volume: 
Vol. 231(3) 22-25
Year: 
1993
Abstract: 

Fish and hydroelectric dams are striving to coexist across the country. With conservation groups as well as state and federal agencies pressing for severe controls on water releases, hydropower production has been cut substantially in many cases. At the same time, dam operators have undertaken some sophisticated construction programs to meet the challenge. To date, many strategies employed on the Columbia and Snake Rivers have been both costly and ineffective. The Army Corps of Engineers is trying to address its problems partly with extensive model studies. But, they have found that "the more you learn, the more complicated it gets." Together the failures of the Corps, as well as other federal agencies have caused the power utilities to call for reductions in spending for all fish programs, which they say are ineffective.

Author(s): 

Soast , A. , King , H.

Contact: 
Notes: 

American Rivers produced abstract

Category: 

Fragmentation of river systems: the genetic effects of dams on bull trout (Salvelinus confluentus) in the Clark Fork River syst

Volume: 
Vol. 10, pp. 1153-1164
Year: 
2001
Abstract: 

Migratory bull trout ( Salvelinus confluentus ) historically spawned in tributaries of the Clark Fork River, Montana and inhabited Lake Pend Oreille as subadult and adult fish. However, in 1952 Cabinet Gorge Dam was constructed without fish passage facilities disrupting the connectivity of this system. Since the construction of this dam, bull trout populations in upstream tributaries have been in decline. Each year adult bull trout return to the base of Cabinet Gorge Dam when most migratory bull trout begin their spawning migration. However, the origin of these fish is uncertain. We used eight microsatellite loci to compare bull trout collected at the base of Cabinet Gorge Dam to fish sampled from both above and further downstream from the dam. Our data indicate that Cabinet Gorge bull trout are most likely individuals that hatched in above-dam tributaries, reared in Lake Pend Oreille, and could not return to their natal tributaries to spawn. This suggests that the risk of outbreeding depression associated with passing adults over dams in the Clark Fork system is minimal compared to the potential genetic and demographic benefits to populations located above the dams. 

Author(s): 

Neraas , L.P. , Spruell , P.

Contact: 
Notes: 
Category: 

Pages