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2.
Braz. J. Biol. ; 83: 1-7, 2023. mapas, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-765402

RESUMO

In fisheries, the phenomenon known as fishing down food webs is supposed to be a consequence of overfishing, which would be reflected in a reduction in the trophic level of landings. In such scenarios, the resilience of carnivorous, top predator species is particularly affected, making these resources the first to be depleted. The Serra Spanish mackerel, Scomberomorus brasiliensis, exemplifies a predator resource historically targeted by artisanal fisheries on the Brazilian coast. The present work analyzes landings in three periods within a 50-year timescale on the Parana coast, Southern Brazil, aiming to evaluate whether historical production has supposedly declined. Simultaneously, the diet was analyzed to confirm carnivorous habits and evaluate the trophic level in this region. Surprisingly, the results show that from the 1970's to 2019 Serra Spanish mackerel production grew relatively to other resources, as well as in individual values. The trophic level was calculated as 4.238, similar to other Scomberomorus species, consisting of a case where landings increase over time, despite the high trophic level and large body size of the resource. The results agree with a recent global assessment that has demystified a necessary correlation between high trophic level and overexploitation, but possible factors acting on the present findings are discussed.(AU)


Na pesca, o fenômeno fishing down food webs, ou 'pescando teias tróficas abaixo', expressa a redução do nível trófico na composição das capturas, e tem origem tradicionalmente atribuída à sobrepesca. Sob intenso extrativismo, a resiliência das espécies carnívoras, predadoras de topo, é particularmente afetada, sendo seus estoques os primeiros a entrarem em depleção. A cavala, ou serra, ou sororoca, Scomberomorus brasiliensis, é exemplo de recurso predador historicamente alvo da pesca artesanal, de pequena escala, na costa brasileira. O presente trabalho analisa os valores de desembarque do recurso em três períodos ao longo de 50 anos na costa paranaense, sul do Brasil, com objetivo de avaliar se sua produção tem efetivamente diminuído. Ainda, estuda-se a dieta da espécie na região, para confirmar seus hábitos carnívoros e avaliar o nível trófico na região. Os resultados mostram que, surpreendentemente, dos anos 1970 para 2019 a produção de S. brasiliensis tem aumentado em valores absolutos, bem como relativamente à de outros recursos, em que pese o nível trófico 4,238, similar a outras espécies do gênero. Constata-se que a pesca da cavala na região de estudo constitui um caso de aumento nos desembarques a despeito de elevado nível trófico e grande tamanho corpóreo. Os resultados concordam com recente levantamento em nível mundial, que nega existir correlação necessária entre sobrepesca e nível trófico alto, mas fatores que podem explicar os resultados do presente trabalho são discutidos.(AU)


Assuntos
Animais , Pesqueiros , Cadeia Alimentar , Equilíbrio Ecológico/análise , Dieta
3.
Braz. j. biol ; 83: e245199, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355853

RESUMO

Abstract The present investigation was aimed to examine the concentrations of trace metals including e.g copper (Cu), manganese (Mn), nickel (Ni), and zinc (Zn) in water samples collected from nursery pond of grass carp (Ctenopharyngodon idella) in Bannu Hatchery of Khyber Pakhtunkhwa during the period from April 2018 to January 2019. The temperature and pH of each water sample were measured for the whole study duration. The concentration of Copper (Cu), Manganese (Mn), Nickel (Ni), and Zinc (Zn) in collected water samples were measured in mg/liter by using Atomic Absorption Spectrophotometer. The blank and standard solutions for device calibration Standard solutions i.e., 2.0 mg, 4.0 mg, and 6.0 were used to measure the concentration of these metals in water samples to verify the measurements. The data was statistically analyzed on descriptive statistics (estimation of proportions and standard deviation) used to summarize mean concentration. The results obtained of both temperature and pH of water samples were found in ranged 10 to 36 0C and 7.0 to 8.44; whereas the size of fry stages was ranged from 4.0 to 56.0 mm in total length. The results of investigated metals found in pond water samples are in order of Zn>Mn>Ni>Cu, respectively. As optimum temperature and pH for grass carp were mostly between 15 0C and 30 0C and pH 6.5 to 8.0. It was concluded from obtained results that temperature, pH, and trace metals were found appropriate for the growth of Ctenopharyngodon idella from fry to fingerling stages, but the highest amount of zinc can cause its mortality. It is a preliminary study on grass carp culturing in Bannu fish hatchery so, it would provide useful information for model fish seed production unit in a hatchery.


Resumo A presente investigação teve como objetivo examinar as concentrações de metais traço, incluindo cobre (Cu), manganês (Mn), níquel (Ni) e zinco (Zn) em amostras de água coletadas de viveiro de carpa-capim (Ctenopharyngodon idella) em Incubatório de Bannu de Khyber Pakhtunkhwa durante o período de abril de 2018 a janeiro de 2019. A temperatura e o pH de cada amostra de água foram medidos durante todo o período do estudo. A concentração de cobre (Cu), manganês (Mn), níquel (Ni) e zinco (Zn) nas amostras de água coletadas foi medida em mg / litro usando espectrofotômetro de absorção atômica. As soluções em branco e padrão para as soluções padrão de calibração do dispositivo, ou seja, 2,0 mg, 4,0 mg e 6,0, foram usadas para medir a concentração desses metais em amostras de água para verificar as medições. Os dados foram analisados ​​estatisticamente em estatística descritiva (estimativa de proporções e desvio padrão) usada para resumir a concentração média. Os resultados obtidos tanto de temperatura quanto de pH das amostras de água variaram de 10 a 36 0C e 7,0 a 8,44, enquanto o tamanho dos estágios de alevinos variou de 4,0 a 56,0 mm no comprimento total. Os resultados dos metais investigados encontrados em amostras de água de lagoas são da ordem de Zn > Mn > Ni > Cu, respectivamente. A temperatura e o pH ótimos para a carpa-capim foram principalmente entre 15 0C e 30 0C e pH 6,5 a 8,0. Concluiu-se, a partir dos resultados obtidos, que temperatura, pH e traços de metais foram considerados adequados para o crescimento de Ctenopharyngodon idella desde os estágios de alevinos até alevinos, mas a maior quantidade de zinco pode causar sua mortalidade. É um estudo preliminar sobre a cultura da carpa-capim em incubatório de peixes Bannu, portanto forneceria informações úteis para modelo de unidade de produção de sementes de peixes em um incubatório.


Assuntos
Animais , Carpas , Paquistão , Água , Lagoas , Pesqueiros
4.
Braz. j. biol ; 83: e244494, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285607

RESUMO

Abstract Since water is one of the essentials for life, the presence and quality of water in the habitat is extremely important. Therefore, water quality change and management of Lake Aygır was investigated in this study. For this, water samples collected from the lake and the irrigation pool between May 2015 and May 2016 were analyzed monthly. Spectrophotometric, titrimetric and microbiological methods were used to determine the water quality. According to some water quality regulations, HCO3, NH4, Cu, Mo, Br, fecal coliform and total suspended solid (TSS) values were found above the limit values. The other 29 parameters comply with Turkish national and international legislations. Lake Aygır was negatively affected by the surrounding settlements and agricultural activities. It is thought that the water resource should be monitored periodically and remedial studies should be done to prevent parameters exceeding the limits. However, Lake Aygır was generally suitable for drinking, use, fishing and irrigation.


Resumo Como a água é um dos elementos essenciais para a vida, a presença e a qualidade da água no habitat são extremamente importantes. Portanto, a mudança da qualidade da água e a gestão do lago Aygır foram investigadas neste estudo. Para isso, amostras de água coletadas no lago e na piscina de irrigação entre maio de 2015 e maio de 2016 foram analisadas mensalmente. Métodos espectrofotométricos, titulométricos e microbiológicos foram usados para determinar a qualidade da água. De acordo com alguns regulamentos de qualidade da água, os valores de HCO3, NH4, Cu, Mo, Br, coliformes fecais e total sólido suspenso (TSS) foram encontrados acima dos valores limite. Os outros 29 parâmetros estão em conformidade com as legislações nacionais e internacionais turcas. O lago Aygır foi afetado negativamente pelos assentamentos e atividades agrícolas ao redor. Pensa-se que o recurso hídrico deve ser monitorado periodicamente e estudos corretivos devem ser feitos para evitar que os parâmetros ultrapassem os limites. No entanto, o lago Aygır era geralmente adequado para beber, usar, pescar e irrigar.


Assuntos
Poluentes Químicos da Água/análise , Lagos , Turquia , Qualidade da Água , Monitoramento Ambiental , Pesqueiros
5.
Braz. j. biol ; 83: e246180, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278550

RESUMO

Abstract In fisheries, the phenomenon known as fishing down food webs is supposed to be a consequence of overfishing, which would be reflected in a reduction in the trophic level of landings. In such scenarios, the resilience of carnivorous, top predator species is particularly affected, making these resources the first to be depleted. The Serra Spanish mackerel, Scomberomorus brasiliensis, exemplifies a predator resource historically targeted by artisanal fisheries on the Brazilian coast. The present work analyzes landings in three periods within a 50-year timescale on the Parana coast, Southern Brazil, aiming to evaluate whether historical production has supposedly declined. Simultaneously, the diet was analyzed to confirm carnivorous habits and evaluate the trophic level in this region. Surprisingly, the results show that from the 1970's to 2019 Serra Spanish mackerel production grew relatively to other resources, as well as in individual values. The trophic level was calculated as 4.238, similar to other Scomberomorus species, consisting of a case where landings increase over time, despite the high trophic level and large body size of the resource. The results agree with a recent global assessment that has demystified a necessary correlation between high trophic level and overexploitation, but possible factors acting on the present findings are discussed.


Resumo Na pesca, o fenômeno fishing down food webs, ou 'pescando teias tróficas abaixo', expressa a redução do nível trófico na composição das capturas, e tem origem tradicionalmente atribuída à sobrepesca. Sob intenso extrativismo, a resiliência das espécies carnívoras, predadoras de topo, é particularmente afetada, sendo seus estoques os primeiros a entrarem em depleção. A cavala, ou serra, ou sororoca, Scomberomorus brasiliensis, é exemplo de recurso predador historicamente alvo da pesca artesanal, de pequena escala, na costa brasileira. O presente trabalho analisa os valores de desembarque do recurso em três períodos ao longo de 50 anos na costa paranaense, sul do Brasil, com objetivo de avaliar se sua produção tem efetivamente diminuído. Ainda, estuda-se a dieta da espécie na região, para confirmar seus hábitos carnívoros e avaliar o nível trófico na região. Os resultados mostram que, surpreendentemente, dos anos 1970 para 2019 a produção de S. brasiliensis tem aumentado em valores absolutos, bem como relativamente à de outros recursos, em que pese o nível trófico 4,238, similar a outras espécies do gênero. Constata-se que a pesca da cavala na região de estudo constitui um caso de aumento nos desembarques a despeito de elevado nível trófico e grande tamanho corpóreo. Os resultados concordam com recente levantamento em nível mundial, que nega existir correlação necessária entre sobrepesca e nível trófico alto, mas fatores que podem explicar os resultados do presente trabalho são discutidos.


Assuntos
Animais , Perciformes , Pesqueiros , Brasil , Conservação dos Recursos Naturais , Cadeia Alimentar
6.
PLoS One ; 17(8): e0271172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35930546

RESUMO

It is an increasingly accepted idea that biological diversity stabilizes ecosystem processes and the services they provide to society. By reducing biomass fluctuation, biodiversity could mitigate the impact of changing environmental conditions on rural incomes as long as people exploits a diverse set of natural assets. This effect is analogous to the risk-spreading function of financial portfolios. This paper presents evidence of the portfolio effect for an open-access artisanal fishery in an estuarine ecosystem, located in a Colombian Biosphere Reserve. Using catch statistics from 2002 to 2018, we evaluate the contribution of catch diversity to the stabilization of fishing income. We find that changes in catch composition are related to seasonal and interannual variations in salinity conditions. The portfolio effect arises from asynchronous fluctuations of fish species due to fluctuating environmental conditions. Catch diversification, instead of specialization, help achieve resilient fisheries.


Assuntos
Ecossistema , Pesqueiros , Animais , Biodiversidade , Conservação dos Recursos Naturais , Peixes , Humanos , Caça , Renda
7.
PLoS One ; 17(8): e0271823, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35925974

RESUMO

The recent return of Atlantic bluefin tuna to northern Europe following the recovery of the east Atlantic stock has sparked substantial public and scientific interest. This is particularly true for recreational anglers in Denmark, who often consider Atlantic bluefin tuna to be the catch of a lifetime. This attitude has previously sustained a substantial recreational fishery for bluefin tuna with annual tournaments in Denmark, which peaked in the 1950s before the subsequent collapse of the stock during the 1960s. Several scientific tagging programs have recruited recreational anglers in recent years to help catch and release tagged bluefin tuna. The anglers' investment of time and money in the scientific tagging projects indicate that the recreational fishery could recover in the future. However, the economic aspects of a potential future recreational bluefin tuna fishery remain unknown. We surveyed anglers participating in a scientific catch and release bluefin tuna fishery in Denmark across three years (2018-2020) and calculated the total annual expenditures associated with the activities. Additionally, we estimated the magnitude of the negative impact (i.e., incidental mortalities) on the bluefin tuna stock. Our results show that total annual expenditures by the recreational anglers approached 1,439,540€, totaling 4,318,620€ between 2018 and 2020. We found that recreational bluefin tuna anglers had mean annual expenditures directly related to the bluefin tuna fishing between 7,047€ and 2,176€ with an associated mortality impact on the stock of less than 1 tonne annually. By comparing the mortality impact to the expenditures, we estimate that each dead Atlantic bluefin tuna during the three study years generated 398,163€ in mean annual expenditures, equivalent to approximately 1636€ kg-1. Our study demonstrates significant economic expenditures among recreational anglers who target Atlantic bluefin tuna. This provides a clear example of how a recovery of marine natural capital and related ecosystem services can support development in the blue economy.


Assuntos
Pesqueiros , Atum , Animais , Oceano Atlântico , Ecossistema , Europa (Continente) , Gastos em Saúde
8.
Sci Rep ; 12(1): 13512, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35933511

RESUMO

Phenological diversity in food resources prolongs foraging opportunities for consumers and buffers them against environmental disturbances. Such diversity is particularly important in forage fish such as Pacific herring (Clupea pallasii), which are foundational to coastal food webs and fisheries. While the importance of phenological diversity is well-known from contemporary studies, the extent to which different populations contribute to fisheries over long time scales is mostly unknown. In this study, we investigated the relative contributions of genetically and phenologically distinct herring populations to Indigenous Peoples' food systems over multiple centuries, using ancient DNA extracted from archaeological herring bones. These bones were excavated from two Coast Salish archaeological sites (Burton Acres Shell Midden and Bay Street Shell Midden) in the Puget Sound region, USA. Using genetic stock identification from seven nuclear DNA markers, we showed that catches at the two sites in central Puget Sound were dominated by January-February and March-April spawners, which are the contemporary spawning groups in the vicinity of the sites. However, May spawners were detected in the older Burton Acres assemblage (dated to 910-685 cal BP), and a mixed stock analysis indicated that catches at this site consisted of multiple populations. These results suggest that Coast Salish ancestors used a portfolio of herring populations and benefited from the ecological resource wave created by different spawning groups of herring. This study of ancient DNA allowed us to glimpse into Indigenous traditional food and management systems, and it enabled us to investigate long-term patterns of biodiversity in an ecologically important forage fish species.


Assuntos
DNA Antigo , Peixes , Animais , Pesqueiros , Peixes/genética , Cadeia Alimentar , Alimentos Marinhos
9.
Artigo em Chinês | MEDLINE | ID: mdl-35915946

RESUMO

The main component of the gas in the fish storage tank is hydrogen sulfide. Hydrogen sulfide poisoning is a common occupational chemical poisoning among fishermen in summer, and acute hydrogen sulfide poisoning can manifest as toxic encephalopathy. This paper analyzes a patient with delayed encephalopathy suspected of acute hydrogen sulfide poisoning. The patient was unconscious for 18 days after waking up for 5 days after acute hydrogen sulfide poisoning. After waking up again, there were symptoms such as decreased limb muscle strength, ataxia, swallowing, dysarthria, and the clinical characteristics were significantly different from those of delayed encephalopathy caused by acute carbon monoxide poisoning, such as decreased cognitive function and damage to extrapyramidal system.


Assuntos
Encefalopatias , Intoxicação por Monóxido de Carbono , Sulfeto de Hidrogênio , Síndromes Neurotóxicas , Exposição Ocupacional , Encefalopatias/induzido quimicamente , Intoxicação por Monóxido de Carbono/complicações , Cognição , Pesqueiros , Humanos , Síndromes Neurotóxicas/complicações
10.
Sci Data ; 9(1): 488, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948590

RESUMO

Inland recreational fisheries, found in lakes, rivers, and other landlocked waters, are important to livelihoods, nutrition, leisure, and other societal ecosystem services worldwide. Although recreationally-caught fish are frequently harvested and consumed by fishers, their contribution to food and nutrition has not been adequately quantified due to lack of data, poor monitoring, and under-reporting, especially in developing countries. Beyond limited global harvest estimates, few have explored species-specific harvest patterns, although this variability has implications for fisheries management and food security. Given the continued growth of the recreational fishery sector, understanding inland recreational fish harvest and consumption rates represents a critical knowledge gap. Based on a comprehensive literature search and expert knowledge review, we quantified multiple aspects of global inland recreational fisheries for 81 countries spanning ~192 species. For each country, we assembled recreational fishing participation rate and estimated species-specific harvest and consumption rate. This dataset provides a foundation for future assessments, including understanding nutritional and economic contributions of inland recreational fisheries.


Assuntos
Pesqueiros , Fenômenos Fisiológicos , Animais , Conservação dos Recursos Naturais , Ecossistema , Peixes , Lagos , Rios
11.
Nat Commun ; 13(1): 4381, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945205

RESUMO

Elasmobranchs are heavily impacted by fishing. Catch statistics are grossly underestimated due to missing data from various fishery sectors such as small-scale fisheries. Marine Protected Areas are proposed as a tool to protect elasmobranchs and counter their ongoing depletion. We assess elasmobranchs caught in 1,256 fishing operations with fixed nets carried out in partially protected areas within Marine Protected Areas and unprotected areas beyond Marine Protected Areas borders at 11 locations in 6 Mediterranean countries. Twenty-four elasmobranch species were recorded, more than one-third belonging to the IUCN threatened categories (Vulnerable, Endangered, or Critically Endangered). Catches per unit of effort of threatened and data deficient species were higher (with more immature individuals being caught) in partially protected areas than in unprotected areas. Our study suggests that despite partially protected areas having the potential to deliver ecological benefits for threatened elasmobranchs, poor small-scale fisheries management inside Marine Protected Areas could hinder them from achieving this important conservation objective.


Assuntos
Elasmobrânquios , Pesqueiros , Animais , Conservação dos Recursos Naturais , Humanos
12.
PLoS One ; 17(7): e0258630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35776917

RESUMO

Landings by the multi-gear coastal fleet operating off the Portuguese continental coast include about 300 species, from which only a few are the object of management plans. In this study, daily landings (kg trip-1) are used, along with an effort indicator, vessel length overall (LoA), to obtain landings per unit of effort (LPUE) as a proxy for the species relative abundance, for a total of 48 species. LPUE indices were used as a response variable in linear models where year (2012-2016), season, region (north and south) and NAO index were explanatory variables. Seasonal and regional effects were found to significantly affect species abundance for a total of 41 and 40 species respectively, while year trends were found to be significant for 19 species, and the NAO index for 3 species. LPUE density maps are presented for several selected species and a subsample of trips, where VMS records were available. It is proposed that geographic and seasonal changes in LPUE can be used to understand trends in abundance and obtain information that can be used in support regional management plans.


Assuntos
Pesqueiros , Estações do Ano
13.
PLoS One ; 17(7): e0269490, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35839164

RESUMO

Marine protected areas (MPAs) are widely utilized for conservation of the world's marine resources. Yet, compliance with MPA regulations remains difficult to measure because of limits to human resources and a lack of affordable technologies to automate monitoring over time. The Marine Monitor, an autonomous vessel monitoring, recording, and reporting system leveraging commercial off-the-shelf X-band marine radar to detect and track vessels, was used to monitor five nearshore California MPAs simultaneously and continuously to identify and compare site-specific use patterns over one year. Vessel tracks were classified into two movement patterns to capture likely fishing activity, "focal" or "linear", that corresponded with local targeted species. Some illegal fishing potentially occurred at all sites (7-17% of tracks depending on site) most frequently on weekends and at mid-day, but the majority of activity occurred just outside the MPAs and in the near vicinity suggesting both a high level of compliance with regulations and awareness of MPA boundaries. Time spent engaged in potential fishing activity compared to track counts suggests that unique vessels may spend more time fishing inside area boundaries at some sites than others. The spatial distribution of activity shows distinct concentrations near MPA boundaries at all sites which strongly suggests vessels purposefully target the narrow area at the MPA boundary or "fish the line", a potential acknowledgement of successful spillover. This activity increased significantly during some local fishing seasons. Concentration of activity at MPA boundaries highlights the importance of continuous monitoring at a high spatial and temporal resolution. Reporting of vessel behavior at a fine-scale using radar can help resource managers target enforcement efforts and understand human use patterns near coastal MPAs.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Peixes , Humanos , Radar , Estações do Ano
15.
PLoS One ; 17(7): e0270703, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35834483

RESUMO

Abundance and distribution of commercial marine resources are influenced by environmental variables, which together with fishery patterns may also influence their catchability. However, Catch Per Unit Effort (CPUE) can be standardized in order to remove most of the variability not directly attributable to fish abundance. In the present study, Generalized Additive Models (GAMs) were used to investigate the effect of some environmental and fishery covariates on the spatial distribution and abundance of the Norway lobster Nephrops norvegicus within the Pomo/Jabuka Pits (Central Adriatic Sea) and to include those that resulted significant in a standardization process. N. norvegicus is a commercially important demersal crustacean, altering its catchability over the 24-h cycle and seasons according to its burrowing behavior. A historically exploited fishing ground for this species, since 2015 subject to specific fisheries management measures, is represented by the meso-Adriatic depressions, which are also characterized by particular oceanographic conditions. Both the species behaviour and the features of this study area influence the dynamics of the population offering a challenging case study for a standardization modelling approach. Environmental and catch data were obtained during scientific trawl surveys properly designed to catch N. norvegicus, thus improving the quality of the model input data. Standardization of CPUE from 2 surveys from 2012 to 2019 was conducted building two GAMs for both biomass and density indices. Bathymetry, fishing pressure, dissolved oxygen and salinity proved to be significant drivers influencing catch distribution. After cross validations, the tuned models were then used to predict new indices for the study area and the two survey series by means of informed spatial grids, composed by constant surface cells, to each of which are associated average values of environmental parameters and specific levels of fishing pressure, depending on the management measures in place. The predictions can be used to better describe the structure and the spatio-temporal distribution of the population providing valuable information to evaluate the status of such an important marine resource.


Assuntos
Pesqueiros , Nephropidae , Animais , Ecossistema , Noruega , Alimentos Marinhos
16.
Sci Data ; 9(1): 423, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853904

RESUMO

Knowing the distribution of fish larvae can inform fisheries science and resource management in several ways, by: 1) providing information on spawning areas; 2) identifying key areas to manage and conserve; and 3) helping to understand how fish populations are affected by anthropogenic pressures, such as overfishing and climate change. With the expansion of industrial fishing activity after 1945, there was increased sampling of fish larvae to help better understand variation in fish stocks. However, large-scale larval records are rare and often unavailable. Here we digitize data from Nishikawa et al. (1985), which were collected from 1956-1981 and are near-global (50°N-50°S), seasonal distribution maps of fish larvae of 18 mainly commercial pelagic taxa of the families Scombridae, Xiphiidae, Istiophoridae, Scombrolabracidae, and Scomberesocidae. Data were collected from the Pacific, Atlantic, and Indian Oceans. We present four seasonal 1° × 1° resolution maps per taxa representing larval abundance per grid cell and highlight some of the main patterns. Data are made available as delimited text, raster, and vector files.


Assuntos
Pesqueiros , Atum , Animais , Mudança Climática , Conservação dos Recursos Naturais , Peixes , Larva
17.
Sci Data ; 9(1): 428, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858969

RESUMO

The combustion of fossil fuels is considered a major cause of climate change, which is why the reduction of emissions has become a key goal of the Paris climate agreement. Coherent monitoring of the energy profile of fishing vessels through an energy audit can effectively identify sources of inefficiency, allowing for the deployment of well-informed and cost-efficient remedial interventions. We applied energy audits to a test fleet of ten vessels, representing three typical Mediterranean trawl fisheries: midwater pair trawl, bottom otter trawl, and Rapido beam trawl. Overall, these fisheries use approximately 2.9 litres of fuel per kilogram of landed fish, but the fuel consumption rate varies widely according to gear type and vessel size. This amount of fuel burned from capture to landing generates approximately 7.6 kg∙CO2/kg fish on average. Minimising impacts and energy consumption throughout the product chain may be another essential element needed to reduce the environmental costs of fishing. Our results provided a set of recognised benchmarks that can be used for monitoring progress in this field.


Assuntos
Pegada de Carbono , Pesqueiros , Animais , Mudança Climática
18.
J Acoust Soc Am ; 151(6): 4073, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35778196

RESUMO

Backscattered acoustic energy from a target varies with frequency and carries information about its material properties, size, shape, and orientation. Gas-bearing organisms are strong reflectors of acoustic energy at the commonly used frequencies (∼18-450 kHz) in fishery surveys, but lack of knowledge of their acoustic properties creates large uncertainties in mesopelagic biomass estimates. Improved knowledge about the volume and elongation (i.e., longest to shortest dimension) of swimbladders of mesopelagic fishes has been identified as an important factor to reduce the overall uncertainties in acoustic survey estimates of mesopelagic biomass. In this paper, a finite element approach was used to model gas-filled objects, revealing the structure of the backscattering, also at frequencies well above the main resonance frequency. Similar scattering features were observed in measured broadband backscattering of several individual mesopelagic organisms. A method is suggested for estimating the elongation of a gas-bubble using these features. The method is applied to the in situ measured wideband (33-380 kHz) target strength (TS) of single mesopelagic gas-bearing organisms from two stations in the North Atlantic (NA) and Norwegian Sea (NS). For the selected targets, the method suggested that the average elongation of gas-bladder at the NA and NS stations are 1.49 ± 0.52 and 2.86 ± 0.50, respectively.


Assuntos
Peixes , Bexiga Urinária , Acústica , Sacos Aéreos , Animais , Pesqueiros
19.
Sci Data ; 9(1): 378, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794151

RESUMO

We describe the Australian Shark-Incident Database, formerly known as the Australian Shark-Attack File, which contains comprehensive reports of 1,196 shark bites that have occurred in Australia over 231 years (1791-2022). Data were collated by the Taronga Conservation Society Australia using purpose-designed questionnaires provided to shark-bite victims or witnesses, media reports, and information provided by the department responsible for fisheries in each Australian state (including the Northern Territory). The dataset includes provoked and unprovoked bites from fresh, brackish, and marine waters in Australia. Data span 22 suspected shark species. This dataset will be publicly available, and can be used by analysts to decipher environmental, biological, and social patterns of shark bites in Australia. The information will aid scientists, conservationists, authorities, and members of the public to make informed decisions when implementing or selecting mitigation measures.


Assuntos
Mordeduras e Picadas , Tubarões , Animais , Mordeduras e Picadas/epidemiologia , Bases de Dados Factuais , Pesqueiros , Humanos , Northern Territory
20.
Sci Data ; 9(1): 385, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798793

RESUMO

Monitoring the moulting phenology of American lobsters (Homarus americanus) is important for maintaining sustainable lobster stocks. Changes in lobster landings can affect reproduction and disease susceptibility. Data on lobster moult indicators and on life-history traits (sex, size) were collated from a twelve-year monitoring program (2004-2015) in six lobster fishing areas in Atlantic Canada. A total of 141,659 lobsters were sampled over 1,195 sampling events using a standardized protocol and commercial lobster fishing traps. The dataset contains pleopod stages, estimated hemolymph protein levels (°Brix values) and shell hardness as well as lobster sex and size. Evaluation of sex ratio dynamics is also possible but existing biases in sampling males and females needs to be noted. This dataset is valuable in terms of inferring spatio-temporal trends in the life history of lobsters, as well as in the analysis of their moult cycle, and hence more generally for fisheries science and marine ecology.


Assuntos
Pesqueiros , Nephropidae , Animais , Canadá , Feminino , Masculino , Muda , Reprodução
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