Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery
The direct control of fishing effort as a management tool is of special interest in the Mediterranean, where the lack of effective international management systems and the high diversity of the catches significantly increases the complexity of implementing TAC´s as an indirect control of fishing eff...
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| Format: | Article |
| Language: | English |
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Consejo Superior de Investigaciones Científicas
2003-12-01
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| Series: | Scientia Marina |
| Subjects: | |
| Online Access: | http://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/519 |
| _version_ | 1818599109027692544 |
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| author | Francisco Alemany Federico Álvarez |
| author_facet | Francisco Alemany Federico Álvarez |
| author_sort | Francisco Alemany |
| collection | DOAJ |
| description | The direct control of fishing effort as a management tool is of special interest in the Mediterranean, where the lack of effective international management systems and the high diversity of the catches significantly increases the complexity of implementing TAC´s as an indirect control of fishing effort. However, its enforcement should be based on the precise knowledge of the relationship between the fishing effort and its corresponding fishing mortality. In this sense, the general aim of this study was to develop an approach for analysing this relationship. In order to estimate the annual effective fishing effort on hake, a relational data base including daily landings by vessel and species of trawl fleet based on the port of Palma, Mallorca island (western Mediterranean) during the period 1983-1991 was built. Fishing mortalities were available from VPA. Fishing effort and fishing mortality were split by subfleets or métiers which were identified by cluster analysis. Significant linear relationships between the two parameters were obtained when fishing effort was considered as the number of days in which hake catch was higher than 10 kg multiplied by GRT of correspondent vessels. These CPUE values are mainly obtained when trawlers operate in the muddy bottoms of the shelf and on the upper slope, where hake populations are mostly distributed. On the other hand, no clear trends in catchability by métier were found during the period analysed. |
| first_indexed | 2024-12-16T12:14:22Z |
| format | Article |
| id | doaj.art-b3dab5b5471d40a8bd733fb286ab719f |
| institution | Directory Open Access Journal |
| issn | 0214-8358 1886-8134 |
| language | English |
| last_indexed | 2024-12-16T12:14:22Z |
| publishDate | 2003-12-01 |
| publisher | Consejo Superior de Investigaciones Científicas |
| record_format | Article |
| series | Scientia Marina |
| spelling | doaj.art-b3dab5b5471d40a8bd733fb286ab719f2022-12-21T22:32:09ZengConsejo Superior de Investigaciones CientíficasScientia Marina0214-83581886-81342003-12-0167449149910.3989/scimar.2003.67n4491513Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fisheryFrancisco Alemany0Federico Álvarez1Instituto Español de Oceanografía, Centro Oceanográfico de BalearesInstituto Español de Oceanografía, Centro Oceanográfico de BalearesThe direct control of fishing effort as a management tool is of special interest in the Mediterranean, where the lack of effective international management systems and the high diversity of the catches significantly increases the complexity of implementing TAC´s as an indirect control of fishing effort. However, its enforcement should be based on the precise knowledge of the relationship between the fishing effort and its corresponding fishing mortality. In this sense, the general aim of this study was to develop an approach for analysing this relationship. In order to estimate the annual effective fishing effort on hake, a relational data base including daily landings by vessel and species of trawl fleet based on the port of Palma, Mallorca island (western Mediterranean) during the period 1983-1991 was built. Fishing mortalities were available from VPA. Fishing effort and fishing mortality were split by subfleets or métiers which were identified by cluster analysis. Significant linear relationships between the two parameters were obtained when fishing effort was considered as the number of days in which hake catch was higher than 10 kg multiplied by GRT of correspondent vessels. These CPUE values are mainly obtained when trawlers operate in the muddy bottoms of the shelf and on the upper slope, where hake populations are mostly distributed. On the other hand, no clear trends in catchability by métier were found during the period analysed.http://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/519merluccius merlucciusmétierseffective effortcatchabilitywestern mediterranean |
| spellingShingle | Francisco Alemany Federico Álvarez Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery Scientia Marina merluccius merluccius métiers effective effort catchability western mediterranean |
| title | Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery |
| title_full | Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery |
| title_fullStr | Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery |
| title_full_unstemmed | Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery |
| title_short | Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery |
| title_sort | determination of effective effort on hake merluccius merluccius in a mediterranean trawl fishery |
| topic | merluccius merluccius métiers effective effort catchability western mediterranean |
| url | http://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/519 |
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