Author(s): Einar Tesaker
Linked Author(s): Einar Tesaker
Keywords: No Keywords
Abstract: The fish habitat in a river usually undergoes large changes as a result of the formation and presence of ice cover. The ice period frequently coincides with shallow flows, causing increased potential for local blocking of the flow profile and redistribution of the flow. Changes in the vertical flow and turbulence profiles, reduced oxygen exchange, erosion and relocation of the substrate, restrictions to fish migration, and damage to roe pits are other effects. While research on habitat hydraulics in open surface flows is well in progress, the study of under ice habitat is in the starting phase. The interest so far seems to concentrate on regulated river conditions, where problems are most easily discovered, demands for mitigating measures and actions are in force, and funding of research seems to be easier. This presentation reviews some important effects on fish life caused by the ice. Needs and possibilities for research, including improved methods, instrumentation and facilities for field and laboratory simulations, are finally discussed.
Year: 2000