Larval fish transport: a case study of white bass
bass, fish transport, larvae, migration, spawning, adult, striped bass, morone saxatilis, upstream, flume, models, entrainment
Journal or Book Title
Transactions of the American Fisheries Society
Larval white bass Morone chrysops resisted downstream transport in the Holston River, eastern Tennessee. Despite a short hydraulic-transport time (<20 hours) through the study area (19.8 km), larvae were not transported downstream and out of this region soon after hatching. Recently hatched larvae were collected near a dam that blocks migration of spawning adults at the upper end of the study area; however, downstream from the dam larvae were significantly larger (and older) than expected if they had been transported passively through the area. Larval white bass probably remain near bottom or in other low-velocity refugia that effectively reduce down-stream displacement. Hybrid striped bass Morone saxatilis x white bass larvae 4 mm and longer oriented upstream in our laboratory flume; they swam vigorously and utilized areas of low current velocity to reduce downstream displacement. Retarded downstream transport found in the rivefine environment, coupled with laboratory observations, implies that improvements are needed in models used to estimate entrainment of fish larvae.