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1.
PLoS One ; 16(8): e0254727, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34379635

RESUMO

Increasing attention is paid to the interdependence between the ecological and human dimensions to improve the management of natural resources. Understanding how artisanal fishers see and use the common-pool resources in a co-management system may hold the clue to establishing effective coastal fisheries policies or strengthening existing ones. A more comprehensive planning of the system will also have a bearing on how to reduce conflicts and strengthen social networks. We surveyed artisanal fishers and decision-makers to determine their perceptions about the Management and Exploitation Areas of Benthic Resources (known as MEABR) in Chile's Biobio region. We performed a field study from November 2018 to August 2019, applying a set of questionnaires to determine the ecological and human attributes that contribute to MEABR outcomes, and then constructed composite scores for those attributes according to a multidimensional scaling technique ("Rapfish"). We find that fishers have different perspectives: surprisingly, women highlighted that the institutional dimension was the most influential on MEABR performance, whereas men highlighted the ecological and economic outcomes. The decision-makers' role in the MEABR system was considered adequate, but communication and socialization of regulations were irregular. Results also showed that fishers expressed dissatisfaction with illegal fishing practices (poaching), productivity, profits, and conflicts inside and outside the MEABRs. Our study allowed us to better understand how the MEABR has developed in the region. We recommend strengthening local management strategies with particular attention paid to networking among stakeholders, including gender inclusive relationships.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Pesqueiros , Percepção , Participação dos Interessados , Adulto , Idoso , Chile , Comunicação , Tomada de Decisões , Feminino , Geografia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho da Amostra , Adulto Jovem
2.
Glob Chang Biol ; 27(2): 220-236, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33067925

RESUMO

Marine biota are redistributing at a rapid pace in response to climate change and shifting seascapes. While changes in fish populations and community structure threaten the sustainability of fisheries, our capacity to adapt by tracking and projecting marine species remains a challenge due to data discontinuities in biological observations, lack of data availability, and mismatch between data and real species distributions. To assess the extent of this challenge, we review the global status and accessibility of ongoing scientific bottom trawl surveys. In total, we gathered metadata for 283,925 samples from 95 surveys conducted regularly from 2001 to 2019. We identified that 59% of the metadata collected are not publicly available, highlighting that the availability of data is the most important challenge to assess species redistributions under global climate change. Given that the primary purpose of surveys is to provide independent data to inform stock assessment of commercially important populations, we further highlight that single surveys do not cover the full range of the main commercial demersal fish species. An average of 18 surveys is needed to cover at least 50% of species ranges, demonstrating the importance of combining multiple surveys to evaluate species range shifts. We assess the potential for combining surveys to track transboundary species redistributions and show that differences in sampling schemes and inconsistency in sampling can be overcome with spatio-temporal modeling to follow species density redistributions. In light of our global assessment, we establish a framework for improving the management and conservation of transboundary and migrating marine demersal species. We provide directions to improve data availability and encourage countries to share survey data, to assess species vulnerabilities, and to support management adaptation in a time of climate-driven ocean changes.


Assuntos
Ecossistema , Pesqueiros , Animais , Mudança Climática , Peixes , Inquéritos e Questionários
3.
Rev Biol Trop ; 62(2): 473-82, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25102632

RESUMO

Anadara tuberculosa is one of the most important bivalves along the Western Pacific coast because of its commercial value. Nevertheless, the variability in growth, long-life span, natural mortality and reproductive parameters of this mangrove cockle has not yet been described. The aim of this study was to analyze these life-history traits in three areas of the Southern coast of Ecuador. Empirical and length-based methods were used to estimate these biological parameters. Body size data were collected from the commercial fishery between 2004 and 2011 in landing ports near to the Archipelago of Jambeli [Puerto Bolivar (PB), Puerto Jeli (PJ) and Puerto Hualtaco (PH)]. The von Bertalanffy growth parameters for combined sex were estimated between 70.87 to 93.45mm for L(infinity) and 0.22 to 0.80/year for k. The growth indices (PHI') ranged from 3.17 to 3.85, while the overall growth performance (OGP) ranged from 5.03 to 5.82. The mean of long-life span (t(max)), size and age at maturity (L50% and t50%) were estimated in 7.71 +/- 2.53 years, 39.13 +/- 2.24mm and 1.46 +/- 0.56 years for PB; 9.51 +/- 2.85 years, 37.78 +/- 1.95mm and 1.37 +/- 0.41 years for PJ and 5.81 +/- 2.11 years, 39.73 +/- 3.31mm and 0.94 +/- 0.41 years for PH. Natural mortality (M) ranged from 0.46 to 1.28/year. We concluded that significant intra-specific variation was observed in a temporal scale in PHI' and OGP indices as well as L50% and M. Therefore, temporal changes in these life-history traits should be taken into account when assessing the status of the mangrove cockle fishery.


Assuntos
Bivalves/fisiologia , Animais , Bivalves/classificação , Bivalves/crescimento & desenvolvimento , Equador , Feminino , Estágios do Ciclo de Vida , Masculino , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Especificidade da Espécie
4.
Rev. biol. trop ; 62(2): 473-482, Jun.-Aug. 2014. graf, tab
Artigo em Inglês | LILACS | ID: lil-715445

RESUMO

Anadara tuberculosa is one of the most important bivalves along the Western Pacific coast because of its commercial value. Nevertheless, the variability in growth, longlife span, natural mortality and reproductive parameters of this mangrove cockle has not yet been described. The aim of this study was to analyze these lifehistory traits in three areas of the Southern coast of Ecuador. Empirical and length-based methods were used to estimate these biological parameters. Body size data were collected from the commercial fishery between 2004 and 2011 in landing ports near to the Archipelago of Jambeli [Puerto Bolivar (PB), Puerto Jeli (PJ) and Puerto Hualtaco (PH)]. The von Bertalanffy growth parameters for combined sex were estimated between 70.87 to 93.45mm for L∞ and 0.22 to 0.80/year for k. The growth indices (Φ’) ranged from 3.17 to 3.85, while the overall growth performance (OGP) ranged from 5.03 to 5.82. The mean of long-life span (t max), size and age at maturity (L50% and t50%) were estimated in 7.71±2.53years, 39.13±2.24mm and 1.46±0.56years for PB; 9.51±2.85years, 37.78±1.95mm and 1.37±0.41years for PJ and 5.81±2.11years, 39.73±3.31mm and 0.94±0.41years for PH. Natural mortality (M) ranged from 0.46 to 1.28/year. We concluded that significant intra-specific variation was observed in a temporal scale in Φ’ and OGP indices as well as L50% and M. Therefore, temporal changes in these life-history traits should be taken into account when assessing the status of the mangrove cockle fishery.


La pesquería de la concha prieta (Anadara tuberculosa) es una de las más importantes a lo largo de la costa del Pacifico. Las variaciones intra-especificas en el crecimiento, longevidad, mortalidad natural y parámetros reproductivos de la concha prieta, aún no han sido descritas. Por lo tanto, el objetivo de este estudio fue analizar esos parámetros biológicos en tres áreas al Sur de Ecuador. Métodos empíricos y basados en tallas fueron empleados para estimar los parámetros de historia de vida. Los datos de tallas analizados correspondieron al periodo 2004-2011 y son provenientes del muestreo de los desembarques de los puertos adyacentes al Archipiélago de Jambeli [Puerto Bolivar (PB), Puerto Jeli (PJ) y Puerto Hualtaco (PH)], al Sur de Ecuador. Los parámetros de crecimiento oscilaron entre 70.87 y 93.45mm de L∞ y 0.22 a 0.80/año de k. Mientras que los índices de crecimiento entre 3.17 a 3.85 de Φ’ y 5.03 a 5.82 de OGP. Los valores promedio de longevidad (t max), talla y edad de madurez (L50% y t50%) fueron de 7.71±2.53años, 39.13±2.24mm y 1.46±0.56años en PB; 9.51±2.85años, 37.78±1.95mm y 1.37±0.41años en PJ y de 5.81±2.11años, 39.73±3.31mm y 0.94±0.41años en PH. Las estimaciones de mortalidad natural (M) oscilaron entre 0.46 y 1.28/año. Importantes cambios intra -especificos se observaron a escala temporal tanto en los índices Φ’ y OGP, así como en L50% y M. Por lo tanto, se sugiere considerar las variaciones temporales en los parámetros biológicos de A. tuberculosa, al momento de caracterizar el estatus de su pesquería y más aun si es sometida a altos niveles de extracción.


Assuntos
Animais , Feminino , Masculino , Bivalves/fisiologia , Bivalves/classificação , Bivalves/crescimento & desenvolvimento , Equador , Estágios do Ciclo de Vida , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Especificidade da Espécie
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