Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean

Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean

The spatial pattern of the fauna associated with floating objects in the eastern tropical Pacific (ETP) was analyzed. Different presence indexes for the groups of species caught incidentally in log sets were estimated, using information from the Inter-American Tropical Tuna Commission database (1993...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autor principal: Solana-Sansores, R
Formato: Online
Lenguaje:eng
Publicado: Iniversidad Autónoma de Baja California 2001
Acceso en línea:https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/472
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id oai:cienciasmarinas.com.mx:article-472
record_format ojs
institution Ciencias Marinas
collection OJS
language eng
format Online
author Solana-Sansores, R
spellingShingle Solana-Sansores, R
Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean
author_facet Solana-Sansores, R
author_sort Solana-Sansores, R
title Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean
title_short Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean
title_full Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean
title_fullStr Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean
title_full_unstemmed Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean
title_sort spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern pacific ocean
description The spatial pattern of the fauna associated with floating objects in the eastern tropical Pacific (ETP) was analyzed. Different presence indexes for the groups of species caught incidentally in log sets were estimated, using information from the Inter-American Tropical Tuna Commission database (1993–1997). These indexes allowed a preliminary grouping of species in relation to the percentage of presence in the log sets on floating objects and to school type (solitary or schooling fish). They were then classified using quadratic discriminant functions, with diverse classification criteria: zone, annual period, groups of species and type of floating object. The models were based on several variance and covariance matrices. Three models were selected to classify the associated fauna, using the likelihood ratio test and the reduction observed in the error rates. The results show two zones in the ETP with different composition of groups of species and floating objects of different origin. The Equatorial Countercurrent, located around 4ºN, is the border between these zones. The northern zone presents an associated fauna dominated by adults and recruits of the silky shark (Carcharhinus falciformis) and of the blacktip shark (C. limbatus); by recruits of yellowfin tuna (Thunnus albacares); and, to a lesser extent, by yellowtail (Seriola lalandi). In the southern zone, the recruits of bigeye tuna (T. obesus) predominate. Both zones share fauna that is only found far from the coast, such as the whitetip shark (C. longimanus).
publisher Iniversidad Autónoma de Baja California
publishDate 2001
url https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/472
_version_ 1715723972514938880
spelling oai:cienciasmarinas.com.mx:article-4722019-05-08T19:17:46Z Spatial patterns of the epipelagic species caught incidentally in the tuna fishery on floating objects, in the eastern Pacific Ocean Patrones espaciales de las especies epipelágicas capturadas incidentalmente en la pesca del atún sobre objetos flotantes, en el Océano Pacífico oriental Solana-Sansores, R floating objects species associated with floating objects eastern tropical Pacific tune fishery quadratic discriminant function objetos flotantes fauna asociada con objetos flotantes Océano Pacífico oriental pesca de atún función discriminante cuadrática The spatial pattern of the fauna associated with floating objects in the eastern tropical Pacific (ETP) was analyzed. Different presence indexes for the groups of species caught incidentally in log sets were estimated, using information from the Inter-American Tropical Tuna Commission database (1993–1997). These indexes allowed a preliminary grouping of species in relation to the percentage of presence in the log sets on floating objects and to school type (solitary or schooling fish). They were then classified using quadratic discriminant functions, with diverse classification criteria: zone, annual period, groups of species and type of floating object. The models were based on several variance and covariance matrices. Three models were selected to classify the associated fauna, using the likelihood ratio test and the reduction observed in the error rates. The results show two zones in the ETP with different composition of groups of species and floating objects of different origin. The Equatorial Countercurrent, located around 4ºN, is the border between these zones. The northern zone presents an associated fauna dominated by adults and recruits of the silky shark (Carcharhinus falciformis) and of the blacktip shark (C. limbatus); by recruits of yellowfin tuna (Thunnus albacares); and, to a lesser extent, by yellowtail (Seriola lalandi). In the southern zone, the recruits of bigeye tuna (T. obesus) predominate. Both zones share fauna that is only found far from the coast, such as the whitetip shark (C. longimanus). Se analizaron los patrones espaciales de la fauna asociada con objetos flotantes en el Océano Pacífico oriental (OPO). Para ello, se calcularon diferentes índices de presencia para los grupos de especies capturados incidentalmente en lances de pesca de atún sobre objetos flotantes, utilizando la base de datos de los observadores de la Comisión Interamericana del Atún Tropical (1993 a 1997). Los índices permitieron una primera agrupación de especies con respecto al porcentaje de presencia en los lances de pesca sobre objetos flotantes y al tipo de cardúmenes formados (especies solitarias o en cardúmenes). Posteriormente, de acuerdo con los grupos de especies, zona, periodo anual y tipo de objetos flotantes, se realizó una clasificación por medio del uso de diversos modelos de funciones discriminantes cuadráticas, basados en diferentes estructuras de varianzas y covarianzas. De ellos, se escogieron tres modelos para la clasificación de la fauna de acompañamiento, de acuerdo con las pruebas de razón de verosimilitud y con la reducción de la tasa de error observada. Los resultados muestran la existencia de dos zonas en el OPO, con diferente composición de grupos de especies y origen de los objetos flotantes. Las zonas tienen como frontera común la Contracorriente Ecuatorial localizada, aproximadamente, sobre los 4ºN. La zona norte presenta una fauna asociada con objetos flotantes dominada por adultos y reclutas del grupo de dos especies de tiburón, el sedoso (Carcharhinus falciformis) y el punta negra (C. limbatus); por reclutas de atún aleta amarilla (Thunnus albacares); y, en menor proporción, por el jurel (Seriola lalandi). En la zona sur, por su parte, dominan los reclutas de patudo (T. obesus). Las dos zonas comparten fauna que sólo se encuentra lejos de la costa, como es el caso del tiburón punta blanca (C. longimanus). Iniversidad Autónoma de Baja California 2001-03-06 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Peer-reviewed Article Artículo Arbitrado application/pdf https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/472 10.7773/cm.v27i3.472 Ciencias Marinas; Vol. 27 No. 3 (2001); 445-479 Ciencias Marinas; Vol. 27 Núm. 3 (2001); 445-479 2395-9053 0185-3880 eng https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/472/410

Ejemplares similares