Journal article

Hydropower operations in groundwater-influenced rivers: implications for Atlantic salmon, Salmo salar, early life stage development and survival

R Casas-Mulet, K Alfredsen, A Brabrand, SJ Saltveit

Fisheries Management and Ecology | WILEY | Published : 2016


During their early life stages (egg maturation, hatching, alevin development), between late autumn and early spring, young Atlantic salmon are exposed to surface-groundwater interactions in the hyporheic zone and may depend on influx of subsurface water during periods of regulated low discharge for survival. Two studies, one in a seasonally regulated river and one in a river exposed to hydropeaking, displayed unexpectedly high survival of eggs in surface de-watered areas because of the influx of oxygen-rich subsurface water. Field observations of newly hatched alevins in these two rivers showed them to be more sensitive (i.e. suffered higher mortality from) to surface de-watering than were e..

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Awarded by Research Council of Norway under RCN

Funding Acknowledgements

This work was undertaken through the Research Program Centre for Environmental Design of Renewable Energy (CEDREN), financed by major Norwegian Energy Companies and the Research Council of Norway under RCN Contract 201779. The authors would like to thank the Suldal River Owner's Association and Lundamo Hatchery for providing the eggs for this study. Thanks to to John E. Brittain and Elise King for language improvement. We are also grateful to the two anonymous reviewers for their comments and to the valuable help provided during the editorial that greatly improved the final manuscript.