caa a22 4500 397551444 CHVBK 20180308164751.0 cr unu---uuuuu 161202e199604 xx s 000 0 eng 10.1006/jmsc.1996.0061 doi (NATIONALLICENCE)oxford-10.1006/jmsc.1996.0061 Monitoring fish movement patterns in a reservoir using horizontally scanning split-beam techniques [Elektronische Daten] [Tracey W. Steig, Samuel V. Johnston] Horizontally scanning split-beam hydroacoustics was used to monitor downstream migrating juvenile salmon and steelhead trout smolts (Oncorhynchusspp.). The study was conducted in the reservoir of Rocky Reach Dam on the Columbia River (Washington, USA). The objective was to determine the movement patterns of smolts as they migrated through the reservoir. Scanning split-beam hydroacoustic techniques and three-dimensional target tracking were combined with remote multiplexing with the aim of investigating smolt movement patterns in the reservoir. The trajectory profiles, target strength distributions, and horizontal distributions of the smolts were estimated for each of six different aiming configurations utilizing six different elliptical split-beam transducers. The results of this study were used to determine the optimal location for installing a surface collector and bypass system. This system will be used to collect and bypass smolts past the dam, a safer alternative to passing through the turbines. The results showed that fish migrated downstream primarily along the east side of the reservoir, concentrated in the upper water column. Few fish were seen migrating down the western shoreline. At the southern end of the reservoir, there were areas where the fish congregated into relatively large schools before proceeding on their downstream migration. Following this study, a smolt bypass system has been installed and is currently being evaluated. © 1996 International Council for the Exploration of the Sea Regular Articles nationallicence acoustics nationallicence fish movement nationallicence scanning nationallicence split-beam nationallicence target strength nationallicence Steig Tracey W. Hydroacoustic Technology Inc., 715 NE Northlake Way, Seattle, Washington 98105-6429, USA. aut Johnston Samuel V. Hydroacoustic Technology Inc., 715 NE Northlake Way, Seattle, Washington 98105-6429, USA. aut ICES Journal of Marine Science Oxford University Press 53/2(1996-04), 435-441 1054-3139 53:2<435 1996 53 icesjms https://doi.org/10.1006/jmsc.1996.0061 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1006/jmsc.1996.0061 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Steig Tracey W. Hydroacoustic Technology Inc., 715 NE Northlake Way, Seattle, Washington 98105-6429, USA aut NATIONALLICENCE 700 1- Johnston Samuel V. Hydroacoustic Technology Inc., 715 NE Northlake Way, Seattle, Washington 98105-6429, USA aut NATIONALLICENCE 773 0- ICES Journal of Marine Science Oxford University Press 53/2(1996-04), 435-441 1054-3139 53:2<435 1996 53 icesjms Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford