Semi-pelagic self-adjusting otter boards: effects on the catching performance of a demersal trawl
In this study, we investigate whether replacing conventional seabed-contacting otter boards with semi-pelagic self-adjusting otter (SAO) boards, which have the ability to maintain a given height above the seabed, affects the catch efficiency of a demersal fish trawl. Experimental fishing trials, usi...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2024
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Subjects: | |
Online Access: | https://orbit.dtu.dk/en/publications/00b54090-3d35-4d1c-a62f-1ce192735dab https://doi.org/10.1139/cjfas-2023-0224 |
Summary: | In this study, we investigate whether replacing conventional seabed-contacting otter boards with semi-pelagic self-adjusting otter (SAO) boards, which have the ability to maintain a given height above the seabed, affects the catch efficiency of a demersal fish trawl. Experimental fishing trials, using the alternate haul method, were conducted in the Kattegat and Skagerrak with three otter board configurations using conventional seabed-contacting otter boards; the SAO set to maintain a target height over the seabed of 1 m; and the SAO set to maintain a target height of 5 m. Replacing conventional otter boards with SAO resulted in a loss of catch efficiency for haddock ( Melanogrammus aeglefinus ), whiting ( Merlangius merlangus ), and plaice ( Hippoglossoides platessoides ), while no significant difference was found for cod ( Gadus morhua ), common dab ( Limanda limanda ), and lemon sole ( Microstomus kitt ). When comparing the SAO-1 m and SAO-5 m, it was observed that SAO-5 m resulted in a loss of catch efficiency for haddock and plaice, a minimal reduction for cod, and no significant difference for whiting, common dab, and lemon sole. |
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