A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries
Abstract Due to global declines, skates and sharks have become a focus of marine conservation in recent years. Despite protective measures, they remain vulnerable to bycatch by fisheries, especially bottom-trawls and pose a problem for fisheries management measures that aim to eliminate discards in...
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Language: | English |
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Oxford University Press (OUP)
2015
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Online Access: | http://dx.doi.org/10.1093/icesjms/fsv037 http://academic.oup.com/icesjms/article-pdf/72/6/1861/31226736/fsv037.pdf |
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croxfordunivpr:10.1093/icesjms/fsv037 2024-06-23T07:55:13+00:00 A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries Kynoch, R. J. Fryer, R. J. Neat, F. C. 2015 http://dx.doi.org/10.1093/icesjms/fsv037 http://academic.oup.com/icesjms/article-pdf/72/6/1861/31226736/fsv037.pdf en eng Oxford University Press (OUP) ICES Journal of Marine Science volume 72, issue 6, page 1861-1868 ISSN 1095-9289 1054-3139 journal-article 2015 croxfordunivpr https://doi.org/10.1093/icesjms/fsv037 2024-06-11T04:21:12Z Abstract Due to global declines, skates and sharks have become a focus of marine conservation in recent years. Despite protective measures, they remain vulnerable to bycatch by fisheries, especially bottom-trawls and pose a problem for fisheries management measures that aim to eliminate discards in the future. In the mixed-species bottom-trawl fisheries of the North Atlantic catches can be increased by fitting a length of chain known as a “tickler” in front of the groundgear of the trawl. It was hypothesized that the tickler is especially effective at catching skates and rays that may otherwise escape beneath the net. A trial was undertaken with paired tows with and without the tickler chain. The trial demonstrated that the catch rate of skates and sharks can be significantly lowered by removing the tickler. A set of secondary nets (groundgear bags) attached behind the groundgear of the main net allowed the number of fish escaping under the net to be estimated and showed that the reduction of skates and sharks in the main net was accompanied by an increase in number in the groundgear bags. This suggests that prohibition of the use of tickler chains in areas that are known to be especially important to skates and sharks could have conservation benefits. The removal of the tickler chain had little effect on catch rates of haddock, whiting, and flatfish, but caused a marked decrease in the catch rate of commercially valuable anglerfish. Article in Journal/Newspaper North Atlantic Oxford University Press ICES Journal of Marine Science 72 6 1861 1868 |
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Oxford University Press |
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description |
Abstract Due to global declines, skates and sharks have become a focus of marine conservation in recent years. Despite protective measures, they remain vulnerable to bycatch by fisheries, especially bottom-trawls and pose a problem for fisheries management measures that aim to eliminate discards in the future. In the mixed-species bottom-trawl fisheries of the North Atlantic catches can be increased by fitting a length of chain known as a “tickler” in front of the groundgear of the trawl. It was hypothesized that the tickler is especially effective at catching skates and rays that may otherwise escape beneath the net. A trial was undertaken with paired tows with and without the tickler chain. The trial demonstrated that the catch rate of skates and sharks can be significantly lowered by removing the tickler. A set of secondary nets (groundgear bags) attached behind the groundgear of the main net allowed the number of fish escaping under the net to be estimated and showed that the reduction of skates and sharks in the main net was accompanied by an increase in number in the groundgear bags. This suggests that prohibition of the use of tickler chains in areas that are known to be especially important to skates and sharks could have conservation benefits. The removal of the tickler chain had little effect on catch rates of haddock, whiting, and flatfish, but caused a marked decrease in the catch rate of commercially valuable anglerfish. |
format |
Article in Journal/Newspaper |
author |
Kynoch, R. J. Fryer, R. J. Neat, F. C. |
spellingShingle |
Kynoch, R. J. Fryer, R. J. Neat, F. C. A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries |
author_facet |
Kynoch, R. J. Fryer, R. J. Neat, F. C. |
author_sort |
Kynoch, R. J. |
title |
A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries |
title_short |
A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries |
title_full |
A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries |
title_fullStr |
A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries |
title_full_unstemmed |
A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries |
title_sort |
simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries |
publisher |
Oxford University Press (OUP) |
publishDate |
2015 |
url |
http://dx.doi.org/10.1093/icesjms/fsv037 http://academic.oup.com/icesjms/article-pdf/72/6/1861/31226736/fsv037.pdf |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
ICES Journal of Marine Science volume 72, issue 6, page 1861-1868 ISSN 1095-9289 1054-3139 |
op_doi |
https://doi.org/10.1093/icesjms/fsv037 |
container_title |
ICES Journal of Marine Science |
container_volume |
72 |
container_issue |
6 |
container_start_page |
1861 |
op_container_end_page |
1868 |
_version_ |
1802647702201171968 |