Tracy Fish Collection Facility Studies, California. Volume 25. Survival and Injury of Rainbow Trout (200-300 mm) Passed Through an Archimedes Lift and a Hidrostal Pump at Red Bluff Research Pumping Plant

摘要

Survival, descaling, and injury rates were determined for 200-300 mm fork length rainbow trout Oncorhynchus mykiss passed through an Archimedes lift and a Hidrostal pump at the Bureau of Reclamations Red Bluff Research Pumping Plant, Red Bluff, California. Treatment fish were compared to control fish (released into the lift and pump discharges) for 16 paired trials conducted with the Archimedes lift and 25 paired trials with the Hidrostal pump during April, May, and June 2002. Trials were conducted at several pump speeds. For the Archimedes lift, there were no detectable differences between treatment and control groups in immediate or 96-h survival, scale loss, or frequency of injuries. Mean percent survival at capture and at 96-h was 100 percent for all speeds and groups, with one exception. For the Hidrostal pump, there were statistically detectable differences in immediate and 96-h survival between treatment and control groups. Average immediate survival ranged from 96.4 to 94.4 percent, while 96-h survival ranged from 94.0 to 88.0 percent. Scale loss was low with no detectable differences between treatment and control groups. The mean percent of surviving fish with injuries was low (2.5 to 9.8) for all groups; however, injury rates were significantly higher in the post-treatment group at the 321 revolutions per minute pump speed.