How many fish need to be measured to effectively evaluate trawl selectivity?
Published version. Source at http://doi.org/10.1371/journal.pone.0161512 . License CC BY 4.0 . The aim of this study was to provide practitioners working with trawl selectivity with general and easily understandable guidelines regarding the fish sampling effort necessary during sea trials. In partic...
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Online Access: | https://hdl.handle.net/10037/10718 https://doi.org/10.1371/journal.pone.0161512 |
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ftunivtroemsoe:oai:munin.uit.no:10037/10718 2023-05-15T15:39:10+02:00 How many fish need to be measured to effectively evaluate trawl selectivity? Herrmann, Bent Sistiaga, Manu Berrondo Santos, Juan Sala, Antonello 2016 https://hdl.handle.net/10037/10718 https://doi.org/10.1371/journal.pone.0161512 eng eng Public Library of Science PLoS ONE Herrmann B, Sistiaga MB, Santos, Sala A. How many fish need to be measured to effectively evaluate trawl selectivity?. PLoS ONE. 2016;11(8) FRIDAID 1401292 doi:10.1371/journal.pone.0161512 1932-6203 https://hdl.handle.net/10037/10718 openAccess Fisheries Rations Curve fitting Cod Covariance Simulation and modeling Confidence intervals Mediterranean Sea VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Journal article Tidsskriftartikkel Peer reviewed 2016 ftunivtroemsoe https://doi.org/10.1371/journal.pone.0161512 2021-06-25T17:55:06Z Published version. Source at http://doi.org/10.1371/journal.pone.0161512 . License CC BY 4.0 . The aim of this study was to provide practitioners working with trawl selectivity with general and easily understandable guidelines regarding the fish sampling effort necessary during sea trials. In particular, we focused on how many fish would need to be caught and length measured in a trawl haul in order to assess the selectivity parameters of the trawl at a designated uncertainty level. We also investigated the dependency of this uncertainty level on the experimental method used to collect data and on the potential effects of factors such as the size structure in the catch relative to the size selection of the gear. We based this study on simulated data created from two different fisheries: the Barents Sea cod (Gadus morhua) trawl fishery and the Mediterranean Sea multispecies trawl fishery represented by red mullet (Mullus barbatus). We used these two completely different fisheries to obtain results that can be used as general guidelines for other fisheries. We found that the uncertainty in the selection parameters decreased with increasing number of fish measured and that this relationship could be described by a power model. The sampling effort needed to achieve a specific uncertainty level for the selection parameters was always lower for the covered codend method compared to the paired-gear method. In many cases, the number of fish that would need to be measured to maintain a specific uncertainty level was around 10 times higher for the paired-gear method than for the covered codend method. The trends observed for the effect of sampling effort in the two fishery cases investigated were similar; therefore the guidelines presented herein should be applicable to other fisheries. Article in Journal/Newspaper Barents Sea Gadus morhua University of Tromsø: Munin Open Research Archive Barents Sea PLOS ONE 11 8 e0161512 |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
topic |
Fisheries Rations Curve fitting Cod Covariance Simulation and modeling Confidence intervals Mediterranean Sea VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 |
spellingShingle |
Fisheries Rations Curve fitting Cod Covariance Simulation and modeling Confidence intervals Mediterranean Sea VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Herrmann, Bent Sistiaga, Manu Berrondo Santos, Juan Sala, Antonello How many fish need to be measured to effectively evaluate trawl selectivity? |
topic_facet |
Fisheries Rations Curve fitting Cod Covariance Simulation and modeling Confidence intervals Mediterranean Sea VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 |
description |
Published version. Source at http://doi.org/10.1371/journal.pone.0161512 . License CC BY 4.0 . The aim of this study was to provide practitioners working with trawl selectivity with general and easily understandable guidelines regarding the fish sampling effort necessary during sea trials. In particular, we focused on how many fish would need to be caught and length measured in a trawl haul in order to assess the selectivity parameters of the trawl at a designated uncertainty level. We also investigated the dependency of this uncertainty level on the experimental method used to collect data and on the potential effects of factors such as the size structure in the catch relative to the size selection of the gear. We based this study on simulated data created from two different fisheries: the Barents Sea cod (Gadus morhua) trawl fishery and the Mediterranean Sea multispecies trawl fishery represented by red mullet (Mullus barbatus). We used these two completely different fisheries to obtain results that can be used as general guidelines for other fisheries. We found that the uncertainty in the selection parameters decreased with increasing number of fish measured and that this relationship could be described by a power model. The sampling effort needed to achieve a specific uncertainty level for the selection parameters was always lower for the covered codend method compared to the paired-gear method. In many cases, the number of fish that would need to be measured to maintain a specific uncertainty level was around 10 times higher for the paired-gear method than for the covered codend method. The trends observed for the effect of sampling effort in the two fishery cases investigated were similar; therefore the guidelines presented herein should be applicable to other fisheries. |
format |
Article in Journal/Newspaper |
author |
Herrmann, Bent Sistiaga, Manu Berrondo Santos, Juan Sala, Antonello |
author_facet |
Herrmann, Bent Sistiaga, Manu Berrondo Santos, Juan Sala, Antonello |
author_sort |
Herrmann, Bent |
title |
How many fish need to be measured to effectively evaluate trawl selectivity? |
title_short |
How many fish need to be measured to effectively evaluate trawl selectivity? |
title_full |
How many fish need to be measured to effectively evaluate trawl selectivity? |
title_fullStr |
How many fish need to be measured to effectively evaluate trawl selectivity? |
title_full_unstemmed |
How many fish need to be measured to effectively evaluate trawl selectivity? |
title_sort |
how many fish need to be measured to effectively evaluate trawl selectivity? |
publisher |
Public Library of Science |
publishDate |
2016 |
url |
https://hdl.handle.net/10037/10718 https://doi.org/10.1371/journal.pone.0161512 |
geographic |
Barents Sea |
geographic_facet |
Barents Sea |
genre |
Barents Sea Gadus morhua |
genre_facet |
Barents Sea Gadus morhua |
op_relation |
PLoS ONE Herrmann B, Sistiaga MB, Santos, Sala A. How many fish need to be measured to effectively evaluate trawl selectivity?. PLoS ONE. 2016;11(8) FRIDAID 1401292 doi:10.1371/journal.pone.0161512 1932-6203 https://hdl.handle.net/10037/10718 |
op_rights |
openAccess |
op_doi |
https://doi.org/10.1371/journal.pone.0161512 |
container_title |
PLOS ONE |
container_volume |
11 |
container_issue |
8 |
container_start_page |
e0161512 |
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1766370633577398272 |