Aquatic Biology and Ecology »
Increasingly, there is a regulatory requirement that both upstream and downstream fish passage be maintained at locations where instream structures restrict the natural movements of fish. Studies conducted by NSC have examined fish passage at hydroelectric dams, weirs, control structures, flood gates, culverts, and bridge crossings. Depending on study objectives and the nature and dimensions of the barrier, a variety of methods have been employed to directly or indirectly ascertain fish passage, such as mark and recapture techniques, PIT tags, radio or acoustic transmitters in concert with fixed or mobile receivers, hydroacoustic transducers, traps installed into the upstream exit of fishways, conduit weirs and analyses of total strontium in fins or "point-in-time" strontium analysis of otoliths. NSC, in collaboration with Normandeau Associates, has also assessed the effects to large-bodied boreal fish species after experimental turbine passage at two hydroelectric generating stations in Manitoba.