Skip to main content
U.S. flag

An official website of the United States government

Effects of plunge pool configuration on downstream passage survival of juvenile blueback herring

July 15, 2020

Anadromous alosines are widespread throughout the Northern Hemisphere. Juveniles of this clade are notoriously fragile animals that are at high risk of injury and death associated with passage at hydroelectric facilities. Although turbine mortality is a common concern, conditions encountered when bypassed around these routes may also be hazardous. Downstream bypass structures typically discharge into plunge pools, which are highly turbulent and may cause mechanical injury. We subjected live, actively migrating juvenile blueback herring to a suite of realistic plunge pool conditions (3 m drop, pool depth of 60–180 cm, and discharge of 0.28–1.70 m3/s) and monitored them for ≥ 96 h. Survival was generally higher than expected (>80% in all cases). However, both plunge pool volume and total discharge affected survival with elevated discharge and shallow conditions associated with increased mortality. Mortality was often delayed: rates remained elevated throughout the monitoring period, indicating that survival studies based on shorter periods underestimate total mortality.

Publication Year 2021
Title Effects of plunge pool configuration on downstream passage survival of juvenile blueback herring
DOI 10.1016/j.aaf.2020.05.006
Authors Theodore R. Castro-Santos, Kevin Mulligan, Micah Kieffer, Alexander Haro
Publication Type Article
Publication Subtype Journal Article
Series Title Aquaculture and Fisheries
Index ID 70219007
Record Source USGS Publications Warehouse
USGS Organization Leetown Science Center; Eastern Ecological Science Center