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1.
PLoS One ; 17(6): e0265829, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35657827

RESUMEN

The magnitude of subsidies provided to the fishing sector by governments worldwide is immense-an estimated $35.4 billion USD per year. The majority of these subsidies may be impeding efforts to sustainably manage fisheries by incentivizing overfishing and overcapacity. Recognizing the threat these subsidies pose, the World Trade Organization has set a goal of reaching an agreement that would end fisheries subsidies that contribute to overcapacity, overfishing, and illegal fishing. However, negotiations have been hampered by uncertainty around the likely effects of reforming these subsidies. Here we present a novel method for translating a bioeconomic model into an interactive online decision support tool that draws upon real-world data on fisheries subsidies and industrial fishing activity so users can directly compare the relative ambition levels of different subsidy reform options.


Asunto(s)
Conservación de los Recursos Naturales , Explotaciones Pesqueras
3.
Data Brief ; 27: 104706, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31886327

RESUMEN

This article contains data on subsidies provided to the fisheries sector by maritime countries. The dataset is the culmination of extensive data collection efforts using peer-reviewed and grey literature, national budgets, online databases, websites and other relevant sources (e.g. OECD, World Bank and WTO), in order to estimate the scope and magnitude of global fisheries subsidies. For subsidies where we found evidence of expenditure by a country, we record the total amount alongside the source references and refer to these as 'reported' data. Where evidence is found that a country provides a subsidy but no amount reported, we estimate using various approaches and refer to these as 'modeled' data. Where evidence exists that no subsidy is provided by a country we refer to these null values as 'not found evidence of subsidy'. All amounts were converted to constant 2018 USD using 2017 exchange rates and annual Consumer Price Index averages. The final dataset of 'reported', 'modeled' and 'not found' subsidies for 2018 consists of 13 subsidy types across 152 maritime countries. The dataset, first developed in the early 2000s, now forms part of the global fisheries management infrastructure and is a central tool used by WTO negotiators. The data we provide may be used to support local, regional and global fisheries management decision-making and may have further uses when analysed in combination with other fisheries related data. Interpretation of these data can be found in the associated research article titled "Updated estimates and analysis of global fisheries subsidies" [1].

4.
PLoS One ; 11(10): e0165167, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27780213

RESUMEN

The regionally endemic Galapagos Grouper, locally known as bacalao, is one of the most highly prized finfish species within the Galapagos Marine Reserve (GMR). Concerns of overfishing, coupled with a lack of fishing regulations aimed at this species raises concerns about the current population health. We assessed changes in population health over a 30-year period using three simple indicators: (1) percentage of fish below reproductive size (Lm); (2) percentage of fish within the optimum length interval (Lopt); and (3) percentage of mega-spawners in the catch. Over the assessed period, none of the indicators reached values associated with healthy populations, with all indicators declining over time. Furthermore, the most recent landings data show that the vast majority of the bacalao caught (95.7%,) were below Lm, the number of fish within the Lopt interval was extremely low (4.7%), and there were virtually no mega-spawners (0.2%). Bacalao fully recruit to the fishery 15 cm below the size at which 50% of the population matures. The Spawning Potential Ratio is currently 5% of potential unfished fecundity, strongly suggesting severe overfishing. Our results suggest the need for bacalao-specific management regulations that should include minimum (65 cm TL) and maximum (78 cm TL) landing sizes, slot limits (64-78 cm TL), as well as a closed season during spawning from October to January. It is recognized that these regulations are harsh and will certainly have negative impacts on the livelihoods of fishers in the short term, however, continued inaction will likely result in a collapse of this economically and culturally valuable species. Alternative sources of income should be developed in parallel with the establishment of fishing regulations to limit the socio-economic disruption to the fishing community during the transition to a more sustainable management regime.


Asunto(s)
Explotaciones Pesqueras/economía , Perciformes/fisiología , Animales , Conservación de los Recursos Naturales , Ecosistema , Ecuador , Regulación de la Población , Reproducción , Estaciones del Año , Análisis Espacio-Temporal
5.
PeerJ ; 3: e1270, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26401463

RESUMEN

The Galapagos Sailfin grouper, Mycteroperca olfax, locally known as bacalao and listed as vulnerable by the IUCN, is culturally, economically, and ecologically important to the Galapagos archipelago and its people. It is regionally endemic to the Eastern Tropical Pacific, and, while an important fishery resource that has shown substantial declines in recent years, to date no effective management regulations are in place to ensure the sustainability of the Galapagos fishery for this species. Previous estimates of longevity and size at maturity for bacalao are inconsistent with estimates for congeners, which brings into question the accuracy of prior estimates. We set out to assess the age, growth, and reproductive biology of bacalao in order to provide more accurate life history information to inform more effective fisheries management for this species. The oldest fish in our sample was 21 years old, which is 2-3 times greater than previously reported estimates of longevity. Parameter estimates for the von Bertalanffy growth function (k = 0.11, L ∞ = 110 cm TL, and to = - 1.7 years) show bacalao to grow much slower and attain substantially larger asymptotic maximum length than previous studies. Mean size at maturity (as female) was estimated at 65.3 cm TL, corresponding to a mean age of 6.5 years. We found that sex ratios were extremely female biased (0.009 M:1F), with a large majority of the individuals in our experimental catch being immature (79%). Our results show that bacalao grow slower, live longer, and mature at a much larger size and greater age than previously thought, with very few mature males in the population. These findings have important implications for the fishery of this valuable species and provide the impetus for a long-overdue species management plan to ensure its long-term sustainability.

6.
PeerJ ; 3: e995, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26082874

RESUMEN

Fisheries bycatch is a significant marine conservation issue as valuable fish are wasted and protected species harmed with potential negative ecological and socio-economic consequences. Even though there are indications that the small-scale handline fishery of the Galapagos Marine Reserve has a low selectivity, information on its bycatch has never been published. We used onboard monitoring and interview data to assess the bycatch of the Galapagos handline fishery by estimating the bycatch ratio, determining species compositions of landings and bycatch, identifying fishers' reasons for discarding certain individuals, and revealing historical trends in the bycatch ratio. The estimated bycatch ratio as a function of biomass of 0.40 and a diverse species composition of target catch and bycatch confirmed the low selectivity of this fishery. Most individuals were not landed for economic motivations, either because species (77.4%) or sizes (17.7%) are unmarketable or for regulatory reasons (5.9%). We found that bycatch contributes to growth overfishing of some target species because they are discarded or used as bait before reaching their first maturity. Moreover, over half of interviewees perceived a historical decrease in bycatch ratios that was explained by a diversification of the target catch due to the reduction in abundance of the traditionally most important target species. As some target species show signs of overfishing and to date there are no specific regulations for the finfish fishery species in place, we recommend the implementation of a series of management measures to protect critical life stages of overexploited species and to improve the selectivity of the Galapagos handline fishery.

7.
Rev. biol. trop ; 60(2): 539-551, June 2012. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-657800

RESUMEN

The brown sea cucumber fishery is active in the Galapagos Islands since the year 1991 after its collapse in mainland Ecuador. This paper analyzes the Galapagos Sea cucumber fishery over the past decade and the reasons for its management pitfalls and chronic over fishing, and proposes an improved strategy for estimating stock size and harvest potential. Based on the historical distribution of the fishing fleet and past fishery surveys, 15 macrozones were defined; their areas were estimated from the coastline to the 30m isobaths and the numbers of sample replicates per macrozone were calculated for a density estimate precision of ±25%. Overall stock size was calculated by summing over all macrozones and was multiplied by 0.122 to obtain the annual quota. This multiplier was derived by inserting an exploitation rate of E=0.3 and a published natural mortality value of M=0.17 into Cadimas formula, thereby obtaining a more conservative precautionary quota estimate. Pre-fishery stock densities in 2009 were below the legal threshold value and the fishery remained closed. Mean densities were significantly lower in the deeper (>15m) than in the shallower (<15m) stratum, contrary to fishermen expectations. Through an empirical regression of (log) pre-fishery density versus subsequent annual catch for the period 1998-2008 we found that catches of most years greatly exceeded the here proposed quota explaining the collapsed nature of the stock. Rev. Biol. Trop. 60 (2): 539-551. Epub 2012 June 01.


Este artículo analiza la pesquería del pepino de mar en Galápagos, durante la década pasada y se estudian las razones de su difícil manejo y la sobre-explotación crónica. El objetivo principal de este trabajo fue proponer una estrategia mejorada para estimar el tamano poblacional y el potencial de captura. Se definieron 15 macrozonas, y para ello se tomo en cuenta la distribución histórica de la flota pesquera y los resultados de prospecciones pesqueras pasadas. Las respectivas aéreas fueron estimadas desde la línea de costa hasta la isobata de los 30m. El numero de replicas de muestreo por macrozona fueron calculadas para estimar la densidad poblacional con una precisión del ±25%. El tamano poblacional total fue calculado sumando la densidad poblacional de todas las macrozonas, luego el resultado fue multiplicado por 0.122 para obtener la cuota anual de captura. Este factor de multiplicación fue derivado mediante la fórmula de Cadima, en la cual se considero una tasa de explotación (E) de 0.3 y una tasa de mortalidad natural (M) de 0.17. Estos resultados permitieron obtener una estimación precautoria y más conservadora de la cuota total de captura. La densidad poblacional pre-pesquería en 2009 estuvo por debajo del punto de referencia límite establecido, en consecuencia fue declarada en veda. Las densidades poblacionales promedio fueron significativamente menores a profundidades mayores a los 15m, contrario a lo esperado por los pescadores. A través de una regresión empírica entre el logaritmo de la densidad poblacional pre-pesquería y la subsecuente cuota de captura anual para el periodo 1998-2008, se descubrió que las capturas totales en la mayoría de los años han excedido la cuota de captura propuesta en este articulo, lo que explica el estado actual de este recurso, el cual se encuentra colapsado.


Asunto(s)
Animales , Humanos , Conservación de los Recursos Naturales , Monitoreo del Ambiente/métodos , Explotaciones Pesqueras , Pepinos de Mar , Ecuador , Densidad de Población , Dinámica Poblacional
8.
Rev Biol Trop ; 60(2): 539-51, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23894927

RESUMEN

The brown sea cucumber fishery is active in the Galapagos Islands since the year 1991 after its collapse in mainland Ecuador. This paper analyzes the Galapagos Sea cucumber fishery over the past decade and the reasons for its management pitfalls and chronic over fishing, and proposes an improved strategy for estimating stock size and harvest potential. Based on the historical distribution of the fishing fleet and past fishery surveys, 15 macrozones were defined; their areas were estimated from the coastline to the 30m isobaths and the numbers of sample replicates per macrozone were calculated for a density estimate precision of +/-25%. Overall stock size was calculated by summing over all macrozones and was multiplied by 0.122 to obtain the annual quota. This multiplier was derived by inserting an exploitation rate of E=0.3 and a published natural mortality value of M=0.17 into Cadimas formula, thereby obtaining a more conservative precautionary quota estimate. Pre-fishery stock densities in 2009 were below the legal threshold value and the fishery remained closed. Mean densities were significantly lower in the deeper (>15m) than in the shallower (<15m) stratum, contrary to fishermen expectations. Through an empirical regression of (log) pre-fishery density versus subsequent annual catch for the period 1998-2008 we found that catches of most years greatly exceeded the here proposed quota explaining the collapsed nature of the stock.


Asunto(s)
Conservación de los Recursos Naturales , Monitoreo del Ambiente/métodos , Explotaciones Pesqueras , Pepinos de Mar , Animales , Ecuador , Humanos , Densidad de Población , Dinámica Poblacional
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