Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery
In response to claims that conventional Nordmøre-grids used in the Clarence River penaeid-trawl fishery were occasionally being fouled or blocked during fishing, two experiments were done to examine the utility of modified grids with different installation angles, sizes and profiles, and alternativ...
Main Authors: | , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Universidad Autónoma de Baja California
2004-03-01
|
Series: | Ciencias Marinas |
Subjects: | |
Online Access: | https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/111 |
_version_ | 1797279383313973248 |
---|---|
author | MK Broadhurst DJ Young C Damiano |
author_facet | MK Broadhurst DJ Young C Damiano |
author_sort | MK Broadhurst |
collection | DOAJ |
description |
In response to claims that conventional Nordmøre-grids used in the Clarence River penaeid-trawl fishery were occasionally being fouled or blocked during fishing, two experiments were done to examine the utility of modified grids with different installation angles, sizes and profiles, and alternative industry-developed, behavioral-type bycatch reduction devices (BRDs). In experiment 1, a conventional Nordmøre-grid (600 mm in length, installed at 45º) was compared against a longer grid (1200 mm in length, installed at 21º) and two locally-developed, behavioral-type BRDs. While slightly more difficult to operate than the conventional design, the longer Nordmøre-grid retained similar quantities of penaeids and bycatch; in contrast, both behavioraltype BRDs retained significantly (up to five times) more bycatch and were considered ineffective for use in this fishery. In experiment 2, the conventional Nordmøre-grid was tested against three modified Nordmøre-grids, including a 600-mm-long grid with a curved profile and installed at 45º, and two grids, both 900 mm in length and installed at 28º, but with flat and curved profiles. Only the curved 900-mm Nordmøre-grid caught significantly fewer penaeids and bycatch, although both of the curvedprofile grids appeared to facilitate the release of debris from the trawl. The results are discussed in terms of fishery-specific factors that probably contributed towards the performances of the various BRDs.
|
first_indexed | 2024-03-07T16:24:28Z |
format | Article |
id | doaj.art-4f72eccae9c1406498d56f422c1a2229 |
institution | Directory Open Access Journal |
issn | 0185-3880 2395-9053 |
language | English |
last_indexed | 2024-03-07T16:24:28Z |
publishDate | 2004-03-01 |
publisher | Universidad Autónoma de Baja California |
record_format | Article |
series | Ciencias Marinas |
spelling | doaj.art-4f72eccae9c1406498d56f422c1a22292024-03-03T18:41:15ZengUniversidad Autónoma de Baja CaliforniaCiencias Marinas0185-38802395-90532004-03-01301B10.7773/cm.v30i12.111Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fisheryMK Broadhurst0DJ Young1C Damiano2National Marine Science CentreNational Marine Science CentreNational Marine Science Centre In response to claims that conventional Nordmøre-grids used in the Clarence River penaeid-trawl fishery were occasionally being fouled or blocked during fishing, two experiments were done to examine the utility of modified grids with different installation angles, sizes and profiles, and alternative industry-developed, behavioral-type bycatch reduction devices (BRDs). In experiment 1, a conventional Nordmøre-grid (600 mm in length, installed at 45º) was compared against a longer grid (1200 mm in length, installed at 21º) and two locally-developed, behavioral-type BRDs. While slightly more difficult to operate than the conventional design, the longer Nordmøre-grid retained similar quantities of penaeids and bycatch; in contrast, both behavioraltype BRDs retained significantly (up to five times) more bycatch and were considered ineffective for use in this fishery. In experiment 2, the conventional Nordmøre-grid was tested against three modified Nordmøre-grids, including a 600-mm-long grid with a curved profile and installed at 45º, and two grids, both 900 mm in length and installed at 28º, but with flat and curved profiles. Only the curved 900-mm Nordmøre-grid caught significantly fewer penaeids and bycatch, although both of the curvedprofile grids appeared to facilitate the release of debris from the trawl. The results are discussed in terms of fishery-specific factors that probably contributed towards the performances of the various BRDs. https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/111bycatch reductionshrimpprawnselectivityNordmøre-grid |
spellingShingle | MK Broadhurst DJ Young C Damiano Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery Ciencias Marinas bycatch reduction shrimp prawn selectivity Nordmøre-grid |
title | Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery |
title_full | Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery |
title_fullStr | Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery |
title_full_unstemmed | Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery |
title_short | Effects of Nordmøre-grid angles, profiles and other industry-developed modifications on catches in an Australian penaeid-trawl fishery |
title_sort | effects of nordmore grid angles profiles and other industry developed modifications on catches in an australian penaeid trawl fishery |
topic | bycatch reduction shrimp prawn selectivity Nordmøre-grid |
url | https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/111 |
work_keys_str_mv | AT mkbroadhurst effectsofnordmøregridanglesprofilesandotherindustrydevelopedmodificationsoncatchesinanaustralianpenaeidtrawlfishery AT djyoung effectsofnordmøregridanglesprofilesandotherindustrydevelopedmodificationsoncatchesinanaustralianpenaeidtrawlfishery AT cdamiano effectsofnordmøregridanglesprofilesandotherindustrydevelopedmodificationsoncatchesinanaustralianpenaeidtrawlfishery |