155 resultados para cpue


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Two experimental fishing trials were carried out off the coast of Pernambuco, Brazil, in 1999 and 2001, using a small artisanal longliner. In experiment 1, six-hook baskets with three chemical light-sticks on alternating hooks had significantly higher catch rates than those with zero or with a light-stick on every hook, with most swordfish accounted for by hooks with light-sticks. Analysis of the data from experiment 2 showed no significant difference between electralume attractors, consisting of AA lithium batteries protected by a solid cover and light-sticks that produce a fluorescent light when two chemical products are mixed. Significant differences were detected in mean CPUE by size class, with most swordfish belonging to class 'b' (125-170 cm lower jaw to fork length (LJFL)). No differences, however, were found for swordfish catches in classes 'a' (< 125 cm LJFL) and V, and no evidence was found of interaction between the two factors (attractor and size class). Although there was no significant difference between the total length-frequency distributions of swordfish caught with light-sticks and electralume attractors, signibcant differences were found for fish smaller than 125 cm LJFL, with electralume catches consisting of smaller swordfish than those of gear using light-sticks. (c) 2004 Elsevier B.V. All rights reserved.

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The fisheries for mackerel scad, Decapterus macarellus, are particularly important in Cape Verde, constituting almost 40% of total catches at the peak of the fishery in 1997 and 1998 ( 3700 tonnes). Catches have been stable at a much lower level of about 2 100 tonnes in recent years. Given the importance of mackerel scad in terms of catch weight and local food security, there is an urgent need for updated assessment. Stock assessment was carried out using a Bayesian approach to biomass dynamic modelling. In order to tackle the problem of a non-informative CPUE series, the intrinsic rate of increase, r, was estimated separately, and the ratio B-0/X, initial biomass relative to carrying capacity, was assumed based on available information. The results indicated that the current level of fishing is sustainable. The probability of collapse is low, particularly in the short-term, and it is likely that biomass may increase further above B-msy, indicating a healthy stock level. It would appear that it is relatively safe to increase catches even up to 4000 tonnes. However, the marginal posterior of r was almost identical to the prior, indicating that there is relatively low information content in CPUE. This was also the case in relation to B-0/X There have been substantial increases in fishing efficiency, which have not been adequately captured by the measure used for effort (days or trips), implying that the results may be overly optimistic and should be considered preliminary. (c) 2006 Elsevier B.V. All rights reserved.

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Two experimental fishing trials were carried out off the coast of Pernambuco, Brazil, in 1999 and 2001, using a small artisanal longliner. In experiment 1, six-hook baskets with three chemical light-sticks on alternating hooks had significantly higher catch rates than those with zero or with a light-stick on every hook, with most swordfish accounted for by hooks with light-sticks. Analysis of the data from experiment 2 showed no significant difference between electralume attractors, consisting of AA lithium batteries protected by a solid cover and light-sticks that produce a fluorescent light when two chemical products are mixed. Significant differences were detected in mean CPUE by size class, with most swordfish belonging to class ‘b’ (125–170 cm lower jaw to fork length (LJFL)). No differences, however, were found for swordfish catches in classes ‘a’ (<125 cm LJFL) and ‘b’, and no evidence was found of interaction between the two factors (attractor and size class). Although there was no significant difference between the total length-frequency distributions of swordfish caught with light-sticks and electralume attractors, significant differences were found for fish smaller than 125 cm LJFL, with electralume catches consisting of smaller swordfish than those of gear using light-sticks.

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Teniendo en cuenta el drástico aumento en Colombia y el mundo de la población adulta mayor la pirámide poblacional se ha invertido. Lo que ha generado que cada vez haya más adultos mayores y la esperanza de vida sea mayor. Motivo por el cual surge la importancia de conocer diversos aspectos del envejecimiento, entre ellos los estereotipos. Adicionalmente hay muy poca investigación relacionada con los estereotipos sobre el envejecimiento según el género y el periodo de desarrollo. Levy (2009) encontró que son los jóvenes quienes tienen más estereotipos negativos sobre el envejecimiento pues estos sienten que la vejez está muy lejos de su realidad actual y no es en una amenaza personal. Por otro lado Bodner, Bergman y Cohen (2012), encontraron que son los hombres quienes tienen más estereotipos negativos sobre el envejecimiento. La presente investigación tuvo como objetivo describir el efecto del periodo del desarrollo y el género en los estereotipos sobre el envejecimiento en 860 adultos colombianos. Se midió la variable de estereotipos sobre el envejecimiento a través del cuestionario de Ramírez y Palacios (2015) y el periodo del desarrollo y el género a través de un cuestionario de datos sociodemograficos. Contrario a lo esperado, los resultados mostraron que no existe relación entre los estereotipos negativos con el género, el periodo del desarrollo, ni en la interacción de estos. En cambio, se encontraron diferencias entre los estereotipos positivos el género y el periodo de desarrollo. Se considera importante continuar realizando investigaciones relacionadas con esta temática pues cada vez son más los adultos mayores y la manera en que nos relacionemos con ellos, va a determinar un mejor proceso de envejecimiento para ellos.

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Se desarrolló un Sistema de Información Geográfica (SIG) automatizado para el análisis espacial de las capturas, del esfuerzo pesquero, de la abundancia estimada de especies mediante el índice de Captura por Unidad de Esfuerzo (CPUE) y de su relación con algunos factores ambientales (profundidad, tipo de fondo y temperatura superficial del mar) de la esquería artesanal asentada en la península de Araya, Estado Sucre, República de Venezuela. Este programa automatizado, denominado SIGPAR, fue desarrollado utilizando el lenguaje Microsoft® Visual Basic 6 y la respectiva librería del software SIG Idrisi®, a cuyo menú principal fue agregado un nuevo módulo que facilita la interacción con los usuarios.Palabras claves: Sistema de Información Geográfica (SIG); pesquería artesanal; Península de Araya, Venezuela.AbstractA Geographic Information System (GIS) application software was developed for the spatial analysis of fishing catches, the estimated abundance of species by the Catch per Unit Effort (CPUE) index, and its relationship with various environmental factors (depth, type of bottom, and surface temperature of the sea) of the artisanal fishery based in the Peninsula of Araya, State of Sucre, in Venezuela. This application, named SIGPAR, was developed using Microsoft® Visual Basic 6 and IDRISI®. A menu button was added to the GIS software IDRISI® for convenience of users.Key Words: Geographic Information System (GIS), Artisanal Fisheries, Araya, Venezuela.