Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selection
ABSTRACT Penaeid trawls are poorly selective fishing gears; contributing towards approximately 27% of global marine fisheries discards. Various options are available for mitigating penaeid-trawl bycatch, including gear modifications such as ‘bycatch reduction devices’ (BRDs) or c...
Guardado en:
Autores principales: | , , , , |
---|---|
Lenguaje: | English |
Publicado: |
Pontificia Universidad Católica de Valparaíso. Facultad de Recursos Naturales. Escuela de Ciencias del Mar
2018
|
Materias: | |
Acceso en línea: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-560X2018000400799 |
Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
id |
oai:scielo:S0718-560X2018000400799 |
---|---|
record_format |
dspace |
spelling |
oai:scielo:S0718-560X20180004007992018-11-06Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selectionDuarte,Dérien L.V.Broadhurst,Matt K.Ortega,IleanaPias,Bruno S.Dumont,Luiz F.C. mesh size morphology bycatch penaeid trawl square-mesh selectivity ABSTRACT Penaeid trawls are poorly selective fishing gears; contributing towards approximately 27% of global marine fisheries discards. Various options are available for mitigating penaeid-trawl bycatch, including gear modifications such as ‘bycatch reduction devices’ (BRDs) or codend mesh-size regulations. A precursor to developing modifications is information about the key target and bycatch species in terms of their sizes and morphology. Here we describe the relationships between these characteristics for the southern Brazilian industrial penaeid-trawl fishery within a broader objective of proposing more selective trawl configurations. Catches were sampled during 37 tows. Fifty-two species were caught, including two loggerhead turtles, Caretta caretta, one green turtle, Chelonia mydas, as well as 61 individuals of seven ray species classified as Endangered or Critically Endangered. One penaeid (Pleoticus muelleri) and 11 teleosts were assessed for various morphological relationships. The data demonstrated that both the existing conventionally used 26 mm (stretched mesh opening; SMO) mesh and a legislated size of 30 mm SMO are too small. Using morphological relationships, we propose testing a minimum diamond-shaped mesh size of at least 35 mm and a square-mesh window in the top of the codend comprising at least 48 mm mesh. Such a configuration would probably retain penaeids and larger teleosts, but allow many small teleosts to escape. Anteriorly located grids are also required to reduce the bycatch of charismatic species like turtles and rays. Wide-scale use of such BRDs should considerably reduce bycatches and the ancillary impacts of regional penaeid-trawl fisheries.info:eu-repo/semantics/openAccessPontificia Universidad Católica de Valparaíso. Facultad de Recursos Naturales. Escuela de Ciencias del MarLatin american journal of aquatic research v.46 n.4 20182018-09-01text/htmlhttp://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-560X2018000400799en10.3856/vol46-issue4-fulltext-17 |
institution |
Scielo Chile |
collection |
Scielo Chile |
language |
English |
topic |
mesh size morphology bycatch penaeid trawl square-mesh selectivity |
spellingShingle |
mesh size morphology bycatch penaeid trawl square-mesh selectivity Duarte,Dérien L.V. Broadhurst,Matt K. Ortega,Ileana Pias,Bruno S. Dumont,Luiz F.C. Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selection |
description |
ABSTRACT Penaeid trawls are poorly selective fishing gears; contributing towards approximately 27% of global marine fisheries discards. Various options are available for mitigating penaeid-trawl bycatch, including gear modifications such as ‘bycatch reduction devices’ (BRDs) or codend mesh-size regulations. A precursor to developing modifications is information about the key target and bycatch species in terms of their sizes and morphology. Here we describe the relationships between these characteristics for the southern Brazilian industrial penaeid-trawl fishery within a broader objective of proposing more selective trawl configurations. Catches were sampled during 37 tows. Fifty-two species were caught, including two loggerhead turtles, Caretta caretta, one green turtle, Chelonia mydas, as well as 61 individuals of seven ray species classified as Endangered or Critically Endangered. One penaeid (Pleoticus muelleri) and 11 teleosts were assessed for various morphological relationships. The data demonstrated that both the existing conventionally used 26 mm (stretched mesh opening; SMO) mesh and a legislated size of 30 mm SMO are too small. Using morphological relationships, we propose testing a minimum diamond-shaped mesh size of at least 35 mm and a square-mesh window in the top of the codend comprising at least 48 mm mesh. Such a configuration would probably retain penaeids and larger teleosts, but allow many small teleosts to escape. Anteriorly located grids are also required to reduce the bycatch of charismatic species like turtles and rays. Wide-scale use of such BRDs should considerably reduce bycatches and the ancillary impacts of regional penaeid-trawl fisheries. |
author |
Duarte,Dérien L.V. Broadhurst,Matt K. Ortega,Ileana Pias,Bruno S. Dumont,Luiz F.C. |
author_facet |
Duarte,Dérien L.V. Broadhurst,Matt K. Ortega,Ileana Pias,Bruno S. Dumont,Luiz F.C. |
author_sort |
Duarte,Dérien L.V. |
title |
Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selection |
title_short |
Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selection |
title_full |
Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selection |
title_fullStr |
Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selection |
title_full_unstemmed |
Quantifying the morphology of key species caught in the southern Brazilian penaeid-trawl fishery as a precursor to improving selection |
title_sort |
quantifying the morphology of key species caught in the southern brazilian penaeid-trawl fishery as a precursor to improving selection |
publisher |
Pontificia Universidad Católica de Valparaíso. Facultad de Recursos Naturales. Escuela de Ciencias del Mar |
publishDate |
2018 |
url |
http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-560X2018000400799 |
work_keys_str_mv |
AT duartederienlv quantifyingthemorphologyofkeyspeciescaughtinthesouthernbrazilianpenaeidtrawlfisheryasaprecursortoimprovingselection AT broadhurstmattk quantifyingthemorphologyofkeyspeciescaughtinthesouthernbrazilianpenaeidtrawlfisheryasaprecursortoimprovingselection AT ortegaileana quantifyingthemorphologyofkeyspeciescaughtinthesouthernbrazilianpenaeidtrawlfisheryasaprecursortoimprovingselection AT piasbrunos quantifyingthemorphologyofkeyspeciescaughtinthesouthernbrazilianpenaeidtrawlfisheryasaprecursortoimprovingselection AT dumontluizfc quantifyingthemorphologyofkeyspeciescaughtinthesouthernbrazilianpenaeidtrawlfisheryasaprecursortoimprovingselection |
_version_ |
1714205207200530432 |