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Jaime Mejuto - One of the best experts on this subject based on the ideXlab platform.
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comparative phylogeography of atlantic bluefin tuna and swordfish the combined effects of vicariance secondary contact introgression and population expansion on the regional phylogenies of two highly migratory pelagic fishes
Molecular Phylogenetics and Evolution, 2005Co-Authors: Jaime Alvarado R Bremer, Jordi Vinas, Jaime MejutoAbstract:Abstract Comparative phylogeography has revealed remarkable patterns of concordance in the maternal phylogenies of many species. The phylogeography and historical demography of the mitochondrial control region I for 607 Atlantic bluefin tuna ( Thunnus thynnus ) and 275 swordfish ( Xiphias gladius ) were analyzed to clarify the complex phylogenetic signals in the North Atlantic–Mediterranean region where they are sympatric. Atlantic bluefin tuna mtDNA is polyphyletic, and includes rare sequences sister to Pacific bluefin tuna ( Thunnus orientalis ) and introgressed albacore ( Thunnus alalunga ) sequences. There is no geographic partitioning between Atlantic and Mediterranean samples of Atlantic bluefin tuna ( Φ ST = 0.002). In contrast, Atlantic and Mediterranean swordfish are differentiated ( Φ ST = 0.091) due to the combined effects of vicariance, secondary contact, and dissimilar regional demographic histories. Mediterranean swordfish has substantially less variation, and a more recent history ( τ = 2.42) than that of Atlantic swordfish ( τ = 7.02). In spite of the discordant phylogenetic and phylogeographic signals, the demographic history of Atlantic swordfish and Atlantic bluefin tuna ( τ = 7.51) suggests concordance in the timeline of population expansion. Possible scenarios of cladogenesis, expansion, and contraction, influenced by glacial cycles during the Pleistocene, are formulated.
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mitochondrial dna control region sequences indicate extensive mixing of swordfish Xiphias gladius populations in the atlantic ocean
Canadian Journal of Fisheries and Aquatic Sciences, 1995Co-Authors: Jaime Alvarado R Bremer, Allan J Baker, Jaime MejutoAbstract:Pacific, Atlantic, and Mediterranean populations of the swordfish (Xiphias gladius) are currently considered as separate fisheries management units, and populations in different regions of the Atlantic are thought to constitute different stocks on the basis of recapture data. To test these hypotheses we sequenced hypervariable segments of the control region of mitochondrial DNA in 35 swordfish from three regions of the Atlantic, as well as in 8 and 7 individuals from the Pacific and Mediterranean regions, respectively. Sixty of the 81 variable sites were confined to a 280 base pair stretch in the left domain of the control region, indicating that this segment is a rich source of genetic markers. Thirty-three haplotypes were found that could be assigned to two clades differing by 3.8% on average, and that diverged approximately 550 000 years ago. Clade I haplotypes were ubiquitous, but haplotypes from clade II predominated in the Mediterranean, and thus likely originated there during Pleistocene marine reg...
García-barcelona S. - One of the best experts on this subject based on the ideXlab platform.
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STANDARDIZED CATCH RATES FOR MEDITERRANEAN SWORDFISH (Xiphias gladius LINNAEUS, 1758) FROM THE SPANISH LONGLINE FISHERY. 1988-2018
Centro Oceanográfico de Málaga, 2020Co-Authors: Saber-rodríguez S., Macías-lópez, A.d. David), García-barcelona S., Rioja-garay P., Gómez-vives, M.j. José), Godoy-garrido, M.d. Dolores), Meléndez-vallejo, M.j. José), Puerto-gonzález, M.Á. Ángel), Ortiz-de-urbina-gutiérrez, J.m. María)Abstract:Standardized relative abundance indices for swordfish (Xiphias gladius Linnaeus, 1758) caught by the Spanish surface longline in the western Mediterranean Sea were estimated for the period 1988-2018. Standardized CPUEs in number were estimated through a General Linear Mixed Modeling (GLMM) approach under a negative binomial (NB) error distribution assumption. Standardized CPUEs in biomass were estimated through a General Linear Mixed Modeling (GLMM) approach under a log-normal error distribution assumption. The main factors in the standardization analysis were fishing area and time of the year (quarter). The standardized indices showed notable annual fluctuations without any definite trend for the period under studyEn prens
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Descripción de dos ejemplares de Zu cristatus (Bonelli, 1820) capturados accidentalmente con un palangre semipelágico en el Mediterráneo occidental
'Consorci del Museu de Ciencies Naturals de Barcelona', 2016Co-Authors: García-barcelona S., García-cancela R., Cayuela M. J., De Carlos A., Bañón R., Macías D., Báez J. C.Abstract:Descripció de dos exemplars de Zu cristatus (Bonelli, 1820) capturats accidentalment amb un palangre semipelàgic al Mediterrani occidental En aquest treball es descriuen dos exemplars adults de Zu cristatus (Bonelli, 1820) (Trachipteridae), un exemplar de 87,8 cm i una femella de 103 cm en estat de posta, capturats accidentalment amb un palangre semipelàgic per capturar al peix espasa, Xiphias gladius Linnaeus, 1758 al Mediterrani occidental. En aquest treball s’aporten les primeres dades sobre l’estat sexual descrites per al Mediterrani occidental.Description of two specimens of Zu cristatus (Bonelli, 1820) accidentally captured in midwater longlines in the western Mediterranean Records of Zu cristatus are relatively rare in the Mediterranean. We report two adult Zu cristatus (Bonelli, 1820) (Trachipteridae), one specimen of 87.8 cm (sex unknown) and one of 103 cm (female), that were by-caught by semi-pelagic longline targeting swordfish, Xiphias gladius Linnaeus, 1758 in the western Mediterranean. This paper provided the first data on the sexual state described for the western Mediterranean.Los registros de Zu cristatus son relativamente raros en el Mediterráneo. En el presente trabajo se describen dos ejemplares adultos de Zu cristatus (Bonelli, 1820) (Trachipteridae), un ejemplar de 87,8 cm (sexo indeterminado) y una hembra de 103 cm en estado de puesta, capturados accidentalmente con un palangre semi-pelàgico para capturar al pez espada, Xiphias gladius Linnaeus, 1758 en el Mediterráneo occidental. En este trabajo se aportan los primeros datos sobre el estado sexual descritos para el Mediterráneo occidental
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Descripción de dos ejemplares de Zu cristatus (Bonelli, 1820) capturados accidentalmente con un palangre semipelágico en el Mediterráneo occidental
Museu de Ciències Naturals de Barcelona, 2016Co-Authors: García-barcelona S., García-cancela R., Cayuela M. J.Abstract:Description of two specimens of Zu cristatus (Bonelli, 1820) accidentally captured in midwater longlines in the western Mediterranean Records of Zu cristatus are relatively rare in the Mediterranean. We report two adult Zu cristatus (Bonelli, 1820) (Trachipteridae), one specimen of 87.8 cm (sex unknown) and one of 103 cm (female), that were by-caught by semi-pelagic longline targeting swordfish, Xiphias gladius Linnaeus, 1758 in the western Mediterranean. This paper provided the first data on the sexual state described for the western Mediterranean
Jaime Alvarado R Bremer - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Multilocus Bayesian Estimates of Intra- Oceanic Genetic Differentiation, Connectivity, and Admixture in Atlantic Swordfish (Xiphias gladius L.)
2016Co-Authors: Brad L. Smith, Jordi Vinas, Blanca García-cortés, Shean-ya Yeh, Jaime Alvarado R BremerAbstract:Previous genetic studies of Atlantic swordfish (Xiphias gladius L.) revealed significant differ-entiation among Mediterranean, North Atlantic and South Atlantic populations using both mitochondrial and nuclear DNA data. However, limitations in geographic sampling cover-age, and the use of single loci, precluded an accurate placement of boundaries and of esti-mates of admixture. In this study, we present multilocus analyses of 26 single nucleotide polymorphisms (SNPs) within 10 nuclear genes to estimate population differentiation and admixture based on the characterization of 774 individuals representing North Atlantic, South Atlantic, and Mediterranean swordfish populations. Pairwise FST values, AMOVA, PCoA, and Bayesian individual assignments support the differentiation of swordfish inhabit-ing these three basins, but not the current placement of the boundaries that separate them. Specifically, the range of the South Atlantic population extends beyond 5°N management boundary to 20°N-25°N from 45°W. Likewise the Mediterranean population extends beyond the current management boundary at the Strait of Gibraltar to approximately 10°W. Further, admixture zones, characterized by asymmetric contributions of adjacent populations withi
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Multilocus Bayesian Estimates of Intra-Oceanic Genetic Differentiation, Connectivity, and Admixture in Atlantic Swordfish (Xiphias gladius L.)
2015Co-Authors: Brad L. Smith, Jordi Vinas, Blanca García-cortés, Shean-ya Yeh, Jaime Alvarado R BremerAbstract:Previous genetic studies of Atlantic swordfish (Xiphias gladius L.) revealed significant differentiation among Mediterranean, North Atlantic and South Atlantic populations using both mitochondrial and nuclear DNA data. However, limitations in geographic sampling coverage, and the use of single loci, precluded an accurate placement of boundaries and of estimates of admixture. In this study, we present multilocus analyses of 26 single nucleotide polymorphisms (SNPs) within 10 nuclear genes to estimate population differentiation and admixture based on the characterization of 774 individuals representing North Atlantic, South Atlantic, and Mediterranean swordfish populations. Pairwise FST values, AMOVA, PCoA, and Bayesian individual assignments support the differentiation of swordfish inhabiting these three basins, but not the current placement of the boundaries that separate them. Specifically, the range of the South Atlantic population extends beyond 5°N management boundary to 20°N-25°N from 45°W. Likewise the Mediterranean population extends beyond the current management boundary at the Strait of Gibraltar to approximately 10°W. Further, admixture zones, characterized by asymmetric contributions of adjacent populations within samples, are confined to the Northeast Atlantic. While South Atlantic and Mediterranean migrants were identified within these Northeast Atlantic admixture zones no North Atlantic migrants were identified respectively in these two neighboring basins. Owing to both, the characterization of larger number of loci and a more ample spatial sampling coverage, it was possible to provide a finer resolution of the boundaries separating Atlantic swordfish populations than previous studies. Finally, the patterns of population structure and admixture are discussed in the light of the reproductive biology, the known patterns of dispersal, and oceanographic features that may act as barriers to gene flow to Atlantic swordfish.
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comparative phylogeography of atlantic bluefin tuna and swordfish the combined effects of vicariance secondary contact introgression and population expansion on the regional phylogenies of two highly migratory pelagic fishes
Molecular Phylogenetics and Evolution, 2005Co-Authors: Jaime Alvarado R Bremer, Jordi Vinas, Jaime MejutoAbstract:Abstract Comparative phylogeography has revealed remarkable patterns of concordance in the maternal phylogenies of many species. The phylogeography and historical demography of the mitochondrial control region I for 607 Atlantic bluefin tuna ( Thunnus thynnus ) and 275 swordfish ( Xiphias gladius ) were analyzed to clarify the complex phylogenetic signals in the North Atlantic–Mediterranean region where they are sympatric. Atlantic bluefin tuna mtDNA is polyphyletic, and includes rare sequences sister to Pacific bluefin tuna ( Thunnus orientalis ) and introgressed albacore ( Thunnus alalunga ) sequences. There is no geographic partitioning between Atlantic and Mediterranean samples of Atlantic bluefin tuna ( Φ ST = 0.002). In contrast, Atlantic and Mediterranean swordfish are differentiated ( Φ ST = 0.091) due to the combined effects of vicariance, secondary contact, and dissimilar regional demographic histories. Mediterranean swordfish has substantially less variation, and a more recent history ( τ = 2.42) than that of Atlantic swordfish ( τ = 7.02). In spite of the discordant phylogenetic and phylogeographic signals, the demographic history of Atlantic swordfish and Atlantic bluefin tuna ( τ = 7.51) suggests concordance in the timeline of population expansion. Possible scenarios of cladogenesis, expansion, and contraction, influenced by glacial cycles during the Pleistocene, are formulated.
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mitochondrial dna control region sequences indicate extensive mixing of swordfish Xiphias gladius populations in the atlantic ocean
Canadian Journal of Fisheries and Aquatic Sciences, 1995Co-Authors: Jaime Alvarado R Bremer, Allan J Baker, Jaime MejutoAbstract:Pacific, Atlantic, and Mediterranean populations of the swordfish (Xiphias gladius) are currently considered as separate fisheries management units, and populations in different regions of the Atlantic are thought to constitute different stocks on the basis of recapture data. To test these hypotheses we sequenced hypervariable segments of the control region of mitochondrial DNA in 35 swordfish from three regions of the Atlantic, as well as in 8 and 7 individuals from the Pacific and Mediterranean regions, respectively. Sixty of the 81 variable sites were confined to a 280 base pair stretch in the left domain of the control region, indicating that this segment is a rich source of genetic markers. Thirty-three haplotypes were found that could be assigned to two clades differing by 3.8% on average, and that diverged approximately 550 000 years ago. Clade I haplotypes were ubiquitous, but haplotypes from clade II predominated in the Mediterranean, and thus likely originated there during Pleistocene marine reg...
Mejuto-garcía J. - One of the best experts on this subject based on the ideXlab platform.
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Tracking of the broadbill swordfish, Xiphias gladius, in the central and eastern Nort Atlantic
'Elsevier BV', 2014Co-Authors: Abascal, F.j. Javier), García-cortés B., Mejuto-garcía J., Quintans Manuel, Ramos-cartelle A.Abstract:tA total of 21 swordfish, Xiphias gladius, were tagged with pop-up satellite tags in northern and southeast-ern areas of the North Atlantic Ocean. There were seasonal patterns in the horizontal movements, withfish tagged in the central North Atlantic moving southwards from the end of the year, generally southof 25◦N, and returning to the temperate foraging grounds, north of 40◦N, in spring. Although move-ments mainly took place latitudinally, fish tracks showed connectivity between the north central, northwestern, south eastern and north eastern North Atlantic. Average estimated daily displacements were24.7±19.5 km day−1, and could average up to ∼100 km day−1in some months. The longest track recordedtotaled more than 10,000 km. Swordfish showed remarkable physiological versatility, inhabiting waterswith SSTs ranging from 10.1 to 28.6◦C, and subject to environmental temperatures of c. 4◦C–28◦C, withdaily ranges frequently over 15◦C (mean 9.2 ± 5.7). Fish showed a clear diel pattern in vertical behav-ior, feeding at 300–600 m deep during daytime and staying in the mixed layer at night. There was asignificant relationship between nocturnal depth and moonphase, quarter and sea surface temperature.The results of the present study are in agreement with the current separation between North Atlantic,Mediterranean and South Atlantic stocks, but suggest that the assumption of a single homogeneous stockin the North Atlantic might be overly simplistic. Further tagging studies, with special emphasis in areasand seasons not covered so far and in combination with other techniques, are still needed to elucidatethe uncertainties of Atlantic swordfish stock structure.Postprint1,586
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Stock structure of swordfish (Xiphias gladius) in the Pacific Ocean using microsatellite DNA markers
Centro Oceanográfico de A Coruña, 2024Co-Authors: Kasapidis P., Magoulas A., García-cortés B., Mejuto-garcía J.Abstract:The genetic structure of swordfish (Xiphias gladius) in the Pacific Ocean was assessed by analyzing 594 individuals from 6 different regions, genotyped with 13 microsatellite loci. The results showed very low genetic differentiation among the different geographicalareas, which was not statistically significant. There was a slight evidence for isolation by distance across a U-shaped corridor, as it had been demonstrated by Reeb et al. (2000) using mtDNA, butmore samples and a better geographical coverage are necessary to support this finding. These data confirmed the low genetic differentiation of swordfish within Pacific, which has been already found with other genetic markers.Versión del edito
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An overview of the activity of the Spanish surface longline fleet targeting swordfish (Xiphias gladius) in the Indian Ocean during the period 2003-2006
Centro Oceanográfico de A Coruña, 2024Co-Authors: García-cortés B., Mejuto-garcía J., Ramos-cartelle A.Abstract:This paper presents data on catch, nominal effort and nominal catch rates in 5x5 degree formats of the activity of the Spanish surface longline fleet targeting swordfish (Xiphias gladius) carried out in 2003, 2004 and 2005 in waters of the Indian Ocean. The total nominal catch of swordfish was 4290, 4713 and 5079 tons round weight respectively. For descriptive purposes, graphs and plots are presented showing annual catches, annual nominal effort, and nominal CPUEs by year and sizes categories in a 5x5 degree square format. The information presented also updates previous papers.Versión de auto
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Trials using different hook and bait types in the configuration of the surface longline gear used by the spanish swordfish (Xiphias gladius) fishery in the Pacific ocean
Centro Oceanográfico de A Coruña, 2024Co-Authors: García-cortés B., Ortiz-de-urbina-gutiérrez, J.m. María), Ramos-cartelle A., Mejuto-garcía J.Abstract:Tres tipos de anzuelos y dos tipos de cebos fueron ensayados en dos buques palangreros dirigidos al pez espada (Xiphias gladius) durante 240 días de mar en áreas del Océano Pacífico SE. El empleo de anzuelos circulares en vez del convencional produciría, descensos en las tasa de captura de pez espada de hasta el –23,1%, incrementos moderados de hasta el +5,5% para el marrajo dientuso (Isurus oxyrinchus) e incrementos más considerables de hasta el +55,5% en los peces de pico. Escasos cambios en las tasas de captura se producirían para la tortuga Caretta caretta con el uso de los anzuelos circulares ensayados. Usando pota como cebo en lugar de caballa, en general se producirían descensos en las tasas de captura de la mayoría de especies de peces, excepto en los peces de pico y en la tortuga Caretta caretta, de hasta +31.7% y +8.2%, respectivamente. Los datos de CPUE media estandarizada sugieren que el empleo de combinaciones de los anzuelos-cebos alternativos ensayados en general produciría reducciones entre el –15.8% y –36.4% de la tasa de captura de la especie objetivo pero en general incrementos de la tasa de captura de hasta +86,8% en el caso de peces de pico en relación al uso de la combinación convencional de referencia. La baja interacción ocurrida sobre las tortugas marinas no permitió obtener conclusiones robustas para estas especies, pero sugiere que el uso de pota como cebo tiende a incrementar las tasas de captura de las tortugas frente al uso de caballa. No se produjo ninguna interacción con aves marinas durante todo el experimento.Versión del editor
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Relationship between size, body weights and fin weight of the blue shark (Prionace glauca) caught as bycatch in the spanish surface longline fishery in the Indian Ocean
Centro Oceanográfico de A Coruña, 2024Co-Authors: Espinosa J., García-cortés B., Mejuto-garcía J.Abstract:Un total de 164 observaciones de talla estándar, peso canal, peso canal sin piel y peso de las aletas de la tintorera (Prionace glauca) han sido obtenidas a bordo de un palangrero de superficie español que dirige su actividad a la captura de pez espada (Xiphias gladius) en el Océano Índico. Los factores de conversión entre la talla y los diferentes tipos de pesos en canal fueron obtenidos mediante regresiones lineales y no lineales. Los ratios medios entre el peso de las aletas y el peso en canal de los cuerpos (con y sin piel) fue de 15.97% y 19.2%, respectivamente.Versión del editor
Cayuela M. J. - One of the best experts on this subject based on the ideXlab platform.
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Descripción de dos ejemplares de Zu cristatus (Bonelli, 1820) capturados accidentalmente con un palangre semipelágico en el Mediterráneo occidental
'Consorci del Museu de Ciencies Naturals de Barcelona', 2016Co-Authors: García-barcelona S., García-cancela R., Cayuela M. J., De Carlos A., Bañón R., Macías D., Báez J. C.Abstract:Descripció de dos exemplars de Zu cristatus (Bonelli, 1820) capturats accidentalment amb un palangre semipelàgic al Mediterrani occidental En aquest treball es descriuen dos exemplars adults de Zu cristatus (Bonelli, 1820) (Trachipteridae), un exemplar de 87,8 cm i una femella de 103 cm en estat de posta, capturats accidentalment amb un palangre semipelàgic per capturar al peix espasa, Xiphias gladius Linnaeus, 1758 al Mediterrani occidental. En aquest treball s’aporten les primeres dades sobre l’estat sexual descrites per al Mediterrani occidental.Description of two specimens of Zu cristatus (Bonelli, 1820) accidentally captured in midwater longlines in the western Mediterranean Records of Zu cristatus are relatively rare in the Mediterranean. We report two adult Zu cristatus (Bonelli, 1820) (Trachipteridae), one specimen of 87.8 cm (sex unknown) and one of 103 cm (female), that were by-caught by semi-pelagic longline targeting swordfish, Xiphias gladius Linnaeus, 1758 in the western Mediterranean. This paper provided the first data on the sexual state described for the western Mediterranean.Los registros de Zu cristatus son relativamente raros en el Mediterráneo. En el presente trabajo se describen dos ejemplares adultos de Zu cristatus (Bonelli, 1820) (Trachipteridae), un ejemplar de 87,8 cm (sexo indeterminado) y una hembra de 103 cm en estado de puesta, capturados accidentalmente con un palangre semi-pelàgico para capturar al pez espada, Xiphias gladius Linnaeus, 1758 en el Mediterráneo occidental. En este trabajo se aportan los primeros datos sobre el estado sexual descritos para el Mediterráneo occidental
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Descripción de dos ejemplares de Zu cristatus (Bonelli, 1820) capturados accidentalmente con un palangre semipelágico en el Mediterráneo occidental
Museu de Ciències Naturals de Barcelona, 2016Co-Authors: García-barcelona S., García-cancela R., Cayuela M. J.Abstract:Description of two specimens of Zu cristatus (Bonelli, 1820) accidentally captured in midwater longlines in the western Mediterranean Records of Zu cristatus are relatively rare in the Mediterranean. We report two adult Zu cristatus (Bonelli, 1820) (Trachipteridae), one specimen of 87.8 cm (sex unknown) and one of 103 cm (female), that were by-caught by semi-pelagic longline targeting swordfish, Xiphias gladius Linnaeus, 1758 in the western Mediterranean. This paper provided the first data on the sexual state described for the western Mediterranean
