کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9481815 | 1327237 | 2005 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Selectivity experiments to estimate the effect of escape windows in the Skagerak roundfish fishery
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کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم کشاورزی و بیولوژیک
علوم آبزیان
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The objectives were to measure roundfish selectivity and to test if square-mesh windows inserted in the codend could improve the selectivity. Sea trials were conducted with a commercial trawler in the Skagerak area. Three codend types were tested: (1) a standard codend with 104Â mm meshes; (2) a standard 104Â mm codend with two 85Â mm square-mesh side windows; (3) a standard 104Â mm codend with an 85-mm square-mesh top window. The twin-trawl method was used where one side of the rig had a 35-mm (nominal mesh size) control codend. Hauls of each codend were fitted simultaneously in a fixed- and random-effects model. In total, 24 and 30 hauls of haddock and cod, respectively, were included in the final selectivity analysis. This indicated that insertion of a top window in a standard codend improved the selectivity resulting in a lower selectivity ratio (SR/L50) and a higher L50 for cod and haddock, whereas insertion of side windows gave a lower selectivity ratio for both species, but a higher L50 for cod only. The results suggest that the recent mesh size increase to 120Â mm in a standard codend is not sufficient to reduce the probability of discards to a negligible level with the existing minimum landing sizes.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Fisheries Research - Volume 71, Issue 2, February 2005, Pages 241-245
Journal: Fisheries Research - Volume 71, Issue 2, February 2005, Pages 241-245
نویسندگان
Niels Madsen, Karl-Johan Stæhr,