Estado de explotación del recurso besugo (Epigonus crassicaudus) en Chile
01 May 2005-Investigaciones Marinas (Pontificia Universidad Católica de Valparaíso)-Vol. 33, Iss: 1, pp 57-67
TL;DR: In this paper, the exploitation status of cardinalfish (Epigonus crassicaudus) yielded in Chile between 33° to 41°S was analyzed using a size-structured model with a transition matrix defining the changes among sizes.
Abstract: The exploitation status of cardinalfish (Epigonus crassicaudus) yielded in Chile between 33° to 41°S was analyzed. An indirect assessment was performed between 1997 and 2003 through size-structured model with a transition matrix defining the changes among sizes. The model was calibrated using size structures, official landings, catch-per-unit of effort (CPUE) taken from commercial fishing logbooks and standardized by generalized linear models (GLM). After 7 years of an intense fishery activity, we concluded that the cardinalfish resource in Chile is on the recruitment overfishing limit. On 2003, the spawning biomass with respect to the virginal spawning biomass is close to 40%. The biological references points (BRP) based on spawning per recruit biomass (SPR) support this assesment because the fishing mortality level on 2003 (F act ) was very close to fishing mortality level of 40% of SRP at virginal value (F 40% ).
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TL;DR: In this article, a modelo no lineal with efectos aleatorios (NLEA) was used for verificar the lectura de edades in Otolitos enteros of Epigonus crassicaudus, where two lectores leyeron tres veces in forma independiente and with intervalos of 15 dias entre lecturas.
Abstract: Con el objeto de verificar la lectura de edades en otolitos enteros de besugo Epigonus crassicaudus, dos lectores leyeron tres veces en forma independiente y con intervalos de 15 dias entre lecturas, la estructura anular de los otolitos de 96 peces de entre 20 y 37 cm de longitud total. Ademas, la lectura de edad en otolitos enteros se contrasto con las lecturas en secciones delgadas transversales, comparandose ademas la frecuencia de anillos secundarios mas marcados. Finalmente, se estimaron los parametros de crecimiento en longitud de la funcion de crecimiento de von Bertalanffy (FCBV), admitiendo el error en la determinacion de la edad. Para ello se utilizo un modelo no lineal con efectos aleatorios (NLEA), donde se especifica la estructura de error de la distribucion de edad. La estimacion de los parametros se comparo con la aplicacion de un modelo no lineal estandar (NLE). Los resultados mostraron que la estructura anular registrada en otolitos enteros es determinada con una alta precision. No existen diferencias significativas en la determinacion de la edad entre otolitos enteros y secciones transversales delgadas. Con esta ultima tecnica se contabilizo una mayor frecuencia de anillos secundarios que en otolitos enteros. Las estimaciones de los parametros de crecimiento con el modelo NLEA fueron mas consistentes que los estimados con el modelo NLE. Se concluye que la lectura de edad en otolitos enteros es determinada con una alta precision, constituyendose en una tecnica facil de implementar para vigilar la estructura de edad de besugo. Se confirma que el crecimiento en longitud de la FCVB de besugo esta representado por una longitud asintotica cercana a los 45 cm y un coeficiente de crecimiento del orden de 0,16-0,18 ano-1
4 citations
Cites background from "Estado de explotación del recurso b..."
...En Chile, el besugo Epigonus crassicaudus (de Buen, 1959) es un pez demersal de gran importancia comercial para la pesquería industrial de arrastre que se desarrolla en la zona centro-sur (Wiff et al. 2005, 2008)....
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...En efecto, la fracción juvenil menor a 20 cm no aparece regularmente en las capturas (Gálvez & Rebolledo 2001, Wiff et al. 2005), y ha sido la causa principal de que el método NLE haya estimado valores positivos para el parámetro t0 y sobrestimación del coeficiente de crecimiento k, y subestimación…...
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TL;DR: The spatial distribution patterns of biomass, size structure and morphometric relationships of E. occidentalis and E. pandionis in deep waters of the Colombian Caribbean Sea are described to determine basic life history traits, such as growth, reproduction, recruitment, and mortality.
Abstract: Cardinal fish are commercially valuable species. In the Colombian Caribbean Sea E. occidentalis and E. pandionis occurred in 37and 35% of tows during a research trawl survey (>200 m), respectively and the biology of these vulnerable species is unknown. The aim of this work is to describe the spatial distribution patterns of biomass, size structure and morphometric relationships of E. occidentalis and E. pandionis in deep waters of the Colombian Caribbean Sea. The samples were collected by trawling in depths between 200 and 550 m. No statistical differences were found in size by sexes in both species. In female and male E. occidentalis the growth was isometric, while in female and male E. pandionis it was positive allometric. E. occidentalis occurred mainly in the northern zone of Colombian Caribbean Sea, with highest aggregations off Santa Marta and Riohacha. E. pandionis was distributed in the northern area between Santa Marta and Riohacha and in the southern area between Cartagena and Morrosquillo Gulf. However, before the exploitation of these species is considered, further research is required to determine basic life history traits, such as growth, reproduction, recruitment, and mortality.
4 citations
Cites background from "Estado de explotación del recurso b..."
..., 2011), but currently this fishery is closed (Ojeda et al., 2010; Wiff et al., 2005)....
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...In the deep-water crustacean fishery off Chile, E. craussicaudus was caught as by-catch in a demersal fishery for fishes and crustaceans with a frequency of occurrence of 80% (Queirolo et al., 2011), but currently this fishery is closed (Ojeda et al., 2010; Wiff et al., 2005)....
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TL;DR: Age and growth parameters were estimated for the deep-sea cardinalfish from sagittal otoliths collected between 2012 and 2015 onboard commercial fishing vessels from the South-east Pacific off Chile between 33°04′S and 41°46′S.
Abstract: Age and growth parameters were estimated for the deep-sea cardinalfish (Epigonus crassicaudus) from sagittal otoliths collected between 2012 and 2015 onboard commercial fishing vessels from the South-east Pacific off Chile between 33°04′S and 41°46′S. Von Bertalanffy growth parameters (VBGP) were estimated from assumed annual otolith growth zone counts. The verification of the first annulus of sagittal otoliths was determined by examining in detail daily micro-increments. These data helped inform the interpretation of the annual growth zones from transverse otolith sections. The von Bertalanffy growth model estimated to length-at-age data were asymptotic length (L∞) of 34.1 cm fork length (FL), a growth coefficient (k) of 0.1 cm/year and a t-zero (t0) of −0.85. The maximum ages observed were 67 and 65 years for female and male fish, respectively.
3 citations
01 Jan 2009
TL;DR: In this paper, a nonlinear model with random effects (NLRE) was used to verify the age readings in whole otoliths of cardinalfish Epigonus crassicaudus, and the growth parameters in length of the von Bertalanffy growth function were estimated by admitting ageing error.
Abstract: With the aim of verifying the age readings in whole otoliths of cardinalfish Epigonus crassicaudus, two readers conducted independently three readings, with an elapsed time of 15 days among readings, of the annular structure of otoliths from 96 fish with length ranging between 20 and 37 cm. In addition, the age readings in whole otoliths were compared with readings on thin transverse sections, recording also the frequency of the most marked secondary rings. Finally, the growth parameters in length of the von Bertalanffy growth function (VBGF) were estimated by admitting ageing error. A nonlinear model with random effects (NLRE) was used, in which the error structure of the sampled age distribution is specified. The estimation of the growth parameters was compared with the performance of a standard nonlinear model (SNL) of estimation. The results showed that the annular structure in whole otoliths can be determined with high precision. Also there are not significant differences in the age determination between whole otoliths and thin transverse sections. In the last technique a higher frequency of secondary rings was counted than in whole otoliths. The estimates of growth parameters with NLRE were more consistent than those estimates obtained with the SNL model. It is concluded that the age readings in whole otoliths is determined with high precision, which is an easy technique to be implemented for monitoring the age structure of cardinalfish. It was confirmed that the growth in length of the VBGF for cardinalfish is represented by an asymptotic length close to 45 cm of total length and a growth coefficient ranging between 0.16-0.18 yr -1 .
3 citations
TL;DR: In this paper, an extensive growth chronology was reconstructed from the annual growth of sagittal otoliths as a proxy for somatic growth for the cardinalfish (Epigonus crassicaudus).
3 citations
References
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25 Mar 1999
TL;DR: The results show clear trends in population growth, Mortality, and the Fishing Process, and age Structured Models: Renewal Theory and Assessment Methods show clear patterns in growth, mortality, and migration.
Abstract: 1. Population Growth, Mortality, and the Fishing Process 2. Stock Productivity and Surplus Production 3. Stock and Recruitment 4. Growth and Fecundity 5. Delay-Difference Models 6. Age-Structured Models: Per Recruit and Year-class Models 7. Age Structured Models: Renewal Theory 8. Catch-Age and Age-Structured Assessment Models 9. Size Structured Models and Assessment Methods 10. Migration and Movement 11. Optimal Harvesting
1,972 citations
"Estado de explotación del recurso b..." refers background in this paper
...Se utilizó una versión discreta de los modelos genéricos de rendimiento por recluta (Quinn & Deriso, 1999)....
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...Se estandariza la CPUE de besugo empleando un Modelo Lineal General (MLG), debido a que este tipo de modelos permite incorporar tanto variables continuas como categóricas asociadas con la evolución de la flota y que pueden resultar en cambios de la capturabilidad (Quinn & Deriso, 1999)....
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Book•
01 Jan 1993
TL;DR: In this paper, 31 papers presented in three theme sessions by fisheries scientists from around the world at a Department of Fisheries and Oceans' workshop in 1991 addressed the use, strengths and weaknesses of commonly-used biological reference points; methods for identifying and quantifying uncertainties associated with using various reference points.
Abstract: This volume contains 31 papers presented in three theme sessions by fisheries scientists from around the world at a Department of Fisheries and Oceans' workshop in 1991 Papers presented address the use, strengths and weaknesses of commonly-used biological reference points; methods for identifying and quantifying uncertainties associated with using various reference points; and alternative management strategies or suggested strategies for dealing with novel situations Answers to specific questions relating to fisheries management, compiled by four working groups at the workshop, are included, as well as a list of participants
292 citations
TL;DR: In this paper, the authors present a case study where risk analysis can enhance the value of scientific advice to fishery managers by expressing the uncertainty inherent in stock assessments in terms of biological risk.
Abstract: Risk analysis can enhance the value of scientific advice to fishery managers by expressing the uncertainty inherent in stock assessments in terms of biological risk. I present a case study involvin...
224 citations
TL;DR: The methods used to develop catch rate based indices of relative abundance for the school shark Galeorhinus galeus resource off southern Australia are outlined in this paper, which are based on fitting generalized linear models to catch and effort data for several regions in this fishery.
172 citations
"Estado de explotación del recurso b..." refers background in this paper
...Además, los MLG son flexibles a diferentes formas de analizar la información, en especial en la exploración de diferentes alternativas para la distribución del error (Punt et al., 2000)....
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TL;DR: A length-structured population model, which incorporates von Bertalanffy growth, is used to describe changes in population abundance over time and the parameter estimates of Pacific cod obtained from this algorithm were comparable with the values that were originally used to simulate the data.
Abstract: A length-structured population model, which incorporates von Bertalanffy growth, is used to describe changes in population abundance over time. The model is incorporated into a catch-at-length algo...
100 citations