Reviews in Fish Biology and Fisheries

, Volume 21, Issue 4, pp 713–731

Hydropower-related pulsed-flow impacts on stream fishes: a brief review, conceptual model, knowledge gaps, and research needs

  • Paciencia S. Young
  • Joseph J. CechJr.
  • Lisa C. Thompson
Reviews

DOI: 10.1007/s11160-011-9211-0

Cite this article as:
Young, P.S., Cech, J.J. & Thompson, L.C. Rev Fish Biol Fisheries (2011) 21: 713. doi:10.1007/s11160-011-9211-0

Abstract

The societal benefits of hydropower systems (e.g., relatively clean electrical power, water supply, flood control, and recreation) come with a cost to native stream fishes. We reviewed and synthesized the literature on hydropower-related pulsed flows to guide resource managers in addressing significant impacts while avoiding unnecessary curtailment of hydropower operations. Dams may release pulsed flows in response to needs for peaking power, recreational flows, reservoir storage adjustment for flood control, or to mimic natural peaks in the hydrograph. Depending on timing, frequency, duration, and magnitude, pulsed flows can have adverse or beneficial short and long-term effects on resident or migratory stream fishes. Adverse effects include direct impacts to fish populations due to (1) stranding of fishes along the changing channel margins, (2) downstream displacement of fishes, and (3) reduced spawning and rearing success due to redd/nest dewatering and untimely or obstructed migration. Beneficial effects include: (1) maintenance of habitat for spawning and rearing, and (2) biological cues to trigger spawning, hatching, and migration. We developed a basic conceptual model to predict the effects of different types of pulsed flow, identified gaps in knowledge, and identified research activities to address these gaps. There is a clear need for a quantitative framework incorporating mathematical representations of field and laboratory results on flow, temperature, habitat structure, fish life stages by season, fish population dynamics, and multiple fish species, which can be used to predict outcomes and design mitigation strategies in other regulated streams experiencing pulsed flows.

Keywords

Pulsed flow releasesHydropowerFish strandingDownstream displacement

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Paciencia S. Young
    • 1
  • Joseph J. CechJr.
    • 2
  • Lisa C. Thompson
    • 2
  1. 1.Department of Biological and Agricultural EngineeringUniversity of CaliforniaDavisUSA
  2. 2.Department of Wildlife, Fish, and Conservation BiologyUniversity of CaliforniaDavisUSA