Concurrent Sessions D: Fish Passage Around the World-II - Recent River Rehabilitation Measures in Swedish Rivers
Location
Agriculture Science Theater, Oregon State University
Start Date
26-6-2013 4:10 PM
End Date
26-6-2013 4:30 PM
Description
River rehabilitation in Europe has increased during the last decade, and in countries like Sweden the activities have moved from mainly addressing salmonid upstream passage and habitat rehabilitation, to also incorporating e.g. creating artificial habitat (nature-like design) to compensate for destroyed habitat and technical solutions for improved downstream passage. Nature-like design and downstream passage rehabilitation have quickly become hot topics in Northern Europe, and so there is a growing interest for finding similar successful projects in other countries. Transferring knowledge from rehabilitation projects from other parts of the world, to your own, is challenging since the solutions in most cases have to be adapted to the species composition, climate, and budget in question. I will present examples of rehabilitation projects from Swedish rivers dealing with nature-like design and downstream passage. The first example is on exploring the potential of nature-like design, moving from nature-like fishways as upstream passage routes for adult salmonids, to multipurpose channels. We investigated if increasing habitat heterogeneity in a nature-like fishway had a positive effect on the overall aquatic biodiversity. The other examples are on the design and evaluation of technical solutions to improved downstream passage for several fish species, in particular the critically endangered European eel (Anguilla anguilla). The solutions for improved downstream passage have until now consisted of low-sloping (35°) intake iron racks guiding fish to the surface. A recently completed collection facility is equipped with composite racks with adjustable angles, and during 2013 the first rack guiding fish to a lateral bypass will be built and evaluated. The current ideas and problems with design are presented and discussed.
Concurrent Sessions D: Fish Passage Around the World-II - Recent River Rehabilitation Measures in Swedish Rivers
Agriculture Science Theater, Oregon State University
River rehabilitation in Europe has increased during the last decade, and in countries like Sweden the activities have moved from mainly addressing salmonid upstream passage and habitat rehabilitation, to also incorporating e.g. creating artificial habitat (nature-like design) to compensate for destroyed habitat and technical solutions for improved downstream passage. Nature-like design and downstream passage rehabilitation have quickly become hot topics in Northern Europe, and so there is a growing interest for finding similar successful projects in other countries. Transferring knowledge from rehabilitation projects from other parts of the world, to your own, is challenging since the solutions in most cases have to be adapted to the species composition, climate, and budget in question. I will present examples of rehabilitation projects from Swedish rivers dealing with nature-like design and downstream passage. The first example is on exploring the potential of nature-like design, moving from nature-like fishways as upstream passage routes for adult salmonids, to multipurpose channels. We investigated if increasing habitat heterogeneity in a nature-like fishway had a positive effect on the overall aquatic biodiversity. The other examples are on the design and evaluation of technical solutions to improved downstream passage for several fish species, in particular the critically endangered European eel (Anguilla anguilla). The solutions for improved downstream passage have until now consisted of low-sloping (35°) intake iron racks guiding fish to the surface. A recently completed collection facility is equipped with composite racks with adjustable angles, and during 2013 the first rack guiding fish to a lateral bypass will be built and evaluated. The current ideas and problems with design are presented and discussed.
Comments
Olle Calles is Associate Professor with the research group Management and Ecology of River Resources at Karlstad University, Sweden. He works on design, implementation and evaluation of rehabilitation techniques for fish in regulated rivers.