caa a22 4500 397550316 CHVBK 20180308164748.0 cr unu---uuuuu 161202e199604 xx s 000 0 eng 10.1006/jmsc.1996.0072 doi (NATIONALLICENCE)oxford-10.1006/jmsc.1996.0072 Aglen Asgeir Institute of Marine Research, PO Box 1870 Nordnes, N-5024 Bergen, Norway Impact of fish distribution and species composition on the relationship between acoustic and swept-area estimates of fish density [Elektronische Daten] [Asgeir Aglen] Bottom-trawl catches were compared with echo-integrator records obtained from a hull-mounted transducer on the towing vessel to examine how far from the bottom fish were available to the trawl. Swept-area density estimates obtained using a length-dependent effective fishing width were converted to equivalent echo-integrator values before being compared with the observed integrator values at different heights above the bottom. For large haddock (Melanogrammus aeglefinus (L.)), saithe (Pollachius virens (L.)), cod (Gadus morhua L.), redfish (Sebastes marinus (L.), and S. viviparus Krøyer) the best correlation between catch and acoustic data was obtained when applying the cumulative acoustic value (from the bottom upward) at 30 to 100 m above the seabed, while for Norway pout (Trisopterus esmarkii Nilsson) the best correlation was obtained at about the height of the headline of the trawl (4 m). Attempts to compensate the acoustic values for losses in the acoustic dead zone did not improve the correlations. © 1996 International Council for the Exploration of the Sea Regular Articles nationallicence acoustic dead zone nationallicence bottom trawl nationallicence echo integration nationallicence fish density estimation nationallicence fishing height nationallicence ICES Journal of Marine Science Oxford University Press 53/2(1996-04), 501-505 1054-3139 53:2<501 1996 53 icesjms https://doi.org/10.1006/jmsc.1996.0072 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1006/jmsc.1996.0072 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Aglen Asgeir Institute of Marine Research, PO Box 1870 Nordnes, N-5024 Bergen, Norway NATIONALLICENCE 773 0- ICES Journal of Marine Science Oxford University Press 53/2(1996-04), 501-505 1054-3139 53:2<501 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