Development of passage structures for adult Pacific lamprey at Bonneville Dam, 2005

Lamprey passage structures (LPSs) can provide passage routes for migrating adult Pacific lamprey Lampetra tridentata in fishway areas where these fish are obstructed or delayed. For example, in 2004, we found that lamprey could successfully pass into the Bonneville Dam forebay via a LPS located in the Bradford Island Auxiliary Water Supply (AWS) channel. Our objectives in 2005 were to modify and evaluate the performance of this LPS and to develop and evaluate a prototype lamprey collector at a Bonneville Dam fishway entrance. Contract no. E96950021