Show simple item record

dc.contributor.authorPerrotta, R.G.
dc.contributor.authorHernandez, D.R.
dc.coverage.spatialAtlantico, Azores
dc.date.accessioned2007-07-10T11:06:47Z
dc.date.available2007-07-10T11:06:47Z
dc.date.issued2005
dc.identifier.citationRevista de Investigación y Desarrollo Pesquero, 17. p. 81-93
dc.identifier.issn0325-6375
dc.identifier.urihttp://hdl.handle.net/1834/1563
dc.description.abstractBluemouth (Helicolenus dactylopterus), a benthic fish mostly inhabiting at depths between 500 m and 600 m, represents a highly valuable economic resource for local fishermen at the Azores Islands (NE Atlantic). Nominal catches of bluemouth increased from 1990 through 1994, and declined afterwards reaching in 1999 the lowest value recorded. Standardized catch per unit effort (CPUE) was used as an index for stock relative abundance; a General Linear Model, considering several factors that may have affected the fishing efficiency of commercial vessels, was run to obtain this CPUE index. These factors were: fleet type, year, month, and boat size; the last three factors were found to be statistically significant. A discrete version of the Schaefers Biomass Dynamic Model was applied to the bluemouth stock assessment and the model parameters were estimated using the standardised CPUE series for calibration. A risk analysis using Monte Carlo simulations was carried out to estimate the probability of the stock biomass at the beginning of 2003 to be below the stock biomass at the beginning of 2002, after a given catch was extracted. Assuming a precautionary approach and keeping in mind that this resource could be depleted (0.19< B2002 /Bopt <1.55, with a 95% probability), this analysis determined that catches for the year 2003 should not exceed 250 t, which correspond to a 10% probability of generating a biomass decline at the beginning of 2003. As an additional indicator of the state of the resource, the size distribution of bluemouth landings was analyzed complementary. This analysis showed a decrease of the mean length, mainly for catches coming from regions with the highest concentrations (depths greater than 300 m). Future annual monitoring efforts to estimate and diagnose the state of the bluemouth resource are highly recommended.en
dc.format.extent387124 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoen
dc.publisherMar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP)
dc.rightsPublisher permission
dc.titleStock assessment of the bluemouth (Helicolenus dactylopterus) in Azorean waters during the 1990-2002 period, applying a biomass dynamic modelen
dc.title.alternativeEvaluación de bocanegra (Helicolenus dactylopterus) en aguas de las Azores durante el período 1990-2002, por medio de un Modelo de Dinámica de Biomasaes
dc.typeJournal Contribution
dc.bibliographicCitation.agscitationNumbervol. 17, p.81-93
dc.bibliographicCitation.endpage93
dc.bibliographicCitation.stpage81
dc.bibliographicCitation.titleRevista de Investigación y Desarrollo Pesqueroes
dc.bibliographicCitation.volume17
dc.description.notesThis work was developed partially at Departamento de Oceanografia e Pescas Marinas (Universidade dos Acores-Portugal)
dc.description.statusPublisheden
dc.description.otherbocanegra
dc.subject.agrovocStock assessmenten
dc.subject.agrovocMathematical modelsen
dc.subject.asfaStock assessmenten
dc.subject.asfaCatch/efforten
dc.subject.asfaRisksen
dc.subject.asfaMathematical modelsen
refterms.dateFOA2021-01-30T18:47:51Z


Files in this item

Thumbnail
Name:
Rev Invest Desarr Pesq 17 81-93.pdf
Size:
378.0Kb
Format:
PDF
Description:
Published version

This item appears in the following Collection(s)

Show simple item record