775 resultados para Sustainable fishery


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Máster en Gestión Sostenible de Recursos Pesqueros

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As a large and long-lived species with high economic value, restricted spawning areas and short spawning periods, the Atlantic bluefin tuna (BFT; Thunnus thynnus) is particularly susceptible to over-exploitation. Although BFT have been targeted by fisheries in the Mediterranean Sea for thousands of years, it has only been in these last decades that the exploitation rate has reached far beyond sustainable levels. An understanding of the population structure, spatial dynamics, exploitation rates and the environmental variables that affect BFT is crucial for the conservation of the species. The aims of this PhD project were 1) to assess the accuracy of larval identification methods, 2) determine the genetic structure of modern BFT populations, 3) assess the self-recruitment rate in the Gulf of Mexico and Mediterranean spawning areas, 4) estimate the immigration rate of BFT to feeding aggregations from the various spawning areas, and 5) develop tools capable of investigating the temporal stability of population structuring in the Mediterranean Sea. Several weaknesses in modern morphology-based taxonomy including demographic decline of expert taxonomists, flawed identification keys, reluctance of the taxonomic community to embrace advances in digital communications and a general scarcity of modern user-friendly materials are reviewed. Barcoding of scombrid larvae revealed important differences in the accuracy of the taxonomic identifications carried out by different ichthyoplanktologists following morphology-based methods. Using a Genotyping-by-Sequencing a panel of 95 SNPs was developed and used to characterize the population structuring of BFT and composition of adult feeding aggregations. Using novel molecular techniques, DNA was extracted from bluefin tuna vertebrae excavated from late iron age, ancient roman settlements Byzantine-era Constantinople and a 20th century collection. A second panel of 96 SNPs was developed to genotype historical and modern samples in order to elucidate changes in population structuring and allele frequencies of loci associated with selective traits.

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The principles of sustainable development (or ecologically sustainable development as it is known in Australia) are now accepted as the foundation for natural resource management worldwide and there are increasing community expectations that they will be implemented explicitly. Previous attempts to assess sustainable development for fisheries have mostly failed because the methods have been too restrictive, often attempting to develop a single set of indicators. In 2000, all the fishery agencies and major stakeholder groups in Australia supported the development of a National ESD Framework. This initiative resulted in a practical system being generated through the results of a series of case studies and stakeholder workshops. The Australian National ESD Framework divides ESD into eight major components within the three main categories of ecological well-being, human well-being and ability to contribute: Four main steps are used to complete an ESD report for a fishery: (1) identify relevant issues, (2) prioritise these using risk assessment, (3) complete appropriately detailed reports on each issue and (4) compile the material into a report. The tools to assist this process are now available and have been used to generate reports for many Australian fisheries. (C) 2004 Elsevier B.V. All rights reserved.

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The failures of traditional target-species management have led many to propose an ecosystem approach to fisheries to promote sustainability. The ecosystem approach is necessary, especially to account for fishery-ecosystem interactions, but by itself is not sufficient to address two important factors contributing to unsustainable fisheries: inappropriate incentives bearing on fishers and the ineffective governance that frequently exists in commercial, developed fisheries managed primarily by total-harvest limits and input controls. We contend that much greater emphasis must be placed on fisher motivation when managing fisheries. Using evidence from more than a dozen natural experiments in commercial fisheries, we argue that incentive-based approaches that better specify community and individual harvest or territorial rights and price ecosystem services and that are coupled with public research, monitoring, and effective oversight promote sustainable fisheries.

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We now live in a world where urbanization has become the norm. Approximately half the world now lives in cities(O'brien, 2008). In recent years for a province like Newfoundland and Labrador which has relied heavily on one industry, the fishery, this statistic holds a lot of meaning. For well over a century there has been a continuing movement from Newfoundland to other parts of Canada and the US. Between 1971 and 1998 alone, net out-migration amounted 20% of the provinces population. This exodus has become a significant part of Newfoundland culture (Bowering Delisle, 2008). Communities have declining populations because families can no longer afford to live in their communities. For places like Corner Brook though citizens do not feel the urge to move to bigger urban centers like St. John's or places on the mainland. The purpose of this paper is to outline values which maybe keeping Corner Brook residents from uprooting their families to move to bigger urban centers such as St. John's, in order to be able to support ther families, get experience in their fields or to just acquire a job like many other people around the province.

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Lake Albert is one of the largest lakes in Uganda that still supports a multi-species fishery which as a result of variable adult sizes of the species, causes management challenges especially in relation to gear mesh size enforcement. Prior to the 1980s, commercial species were 17 large sized fishes especially Citharinus citharinus, Distichodus niloticus and Lates spp. that were confimed to inshore habitats of the lake and were thus rapidly over fished. Frame and catch assessment surveys conducted in this study revealed a >80% dominance of small size fish species (Neobola bredoi and Brycinus nurse) and a 40 -60% decrease in the contribution of the large commercial species. Sustainability of small size fish species is uncertain due to seasonal fluctuations and low beach value. At about 150,000 tons of fish recorded from Lake Albert and Albert Nile, the beach value was estimated at 55.3 million USD. Despite the noted decline in catches of the large sized fishes their contribution was more than 50% of total beach value. Therefore, management measures should couple value addition for the small sized species and maintain effort regulation targeting recovery of the large previously important commercial species.

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This fishery assessment report describes the commercial stout whiting fishery operation along Australia’s east coast between Sandy Cape and the Queensland-New South Wales border. The fishery is identified by a T4 symbol. This study follows methods applied in (O'Neill & Leigh, 2016a) and extends the results of that study by using the latest data available up to end of March 2016. The fishery statistics reported herein are for fishing years 1991 to 2016. This study analysed stout whiting catch rates from both Queensland and New South Wales (NSW) for all vessels, areas and fishing gears. The 2016 catch rate index from Queensland and NSW waters was 0.86. This means that the 2016 catch rate index was 86% of the mean standardised catch rate. Results showed that there was a stable trend in catch rates from 2012 to 2016, as in the previous study (O'Neill & Leigh, 2016a), with the 2015 and 2014 catch rates 85% of the mean catch rate. The fish-length frequency and age-length-otolith data were translated using two models which showed: • Where patterns of fish age-abundance were estimated from the fish-length frequency and age-length data, there were slightly decreased estimated measures of fish survival at 38% for 2014, compared to fish survival estimates in 2013 at 40%. The 2014 and 2015 estimated age structure was dominated by 1+ and 2+ old fished, with a slightly higher frequency of age 2 - 3 fish for 2015. • Where only the age-length data were used, estimates showed that from 2011 to 2014 the survival index increased. The estimated survival index increased from 35% in 2013 to 64% in 2014, indicating stronger survival of fish as they recruited and aged. Together the stout whiting catch rate and survival indicators showed the recent fishery harvests were sustainable. Since 1997, T4 management (Stout Whiting Fishery) is centred on annual assessments of total allowable commercial catch (TACC). The TACC is assessed before the start of each fishing year using statistical assessment methodologies, namely evaluation of trends in fish catch rates and catch-at-age frequencies measured against management reference points. The TACC has been under-caught in many years. For setting the 2017 T4 stout whiting TACC, the calculations covered a range of settings to account for the variance in the data and provide options for quota change. The overall (averaged) results suggested: • The procedure where the quota was adjusted based on previous TACC setting in year 2016 gave a recommended TACC for 2017 of between 1100 and 1130 t. • The procedure that focussed directly on optimising the average harvest to match target reference points gave a recommended TACC for 2017 of between 860 and 890 t. Use of these estimates to set TACC will depend on management and industry aims for the fishery.

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In Queensland, stout whiting are fished by Danish seine and fish otter-trawl methods between Sandy Cape and the Queensland-New South Wales border. The fishery is currently identified by a T4 symbol and is operated by two primary quota holders. Since 1997, T4 management has been informed by annual stock assessments in order to determine a total allowable commercial catch (TACC) quota. The TACC is assessed before the start of each fishing year using statistical methodologies. This includes evaluation of trends in fish catch-rates and catch-at-age frequencies against management reference points. The T4 stout whiting TACC for 2014 was adjusted down to 1150 t as a result of elevated estimates of fishing mortality and remained unchanged in 2015 (2013 TACC = 1350 t quota). Two T4 vessels fished for stout whiting in the 2015 fishing year, harvesting 663 t from Queensland waters. Annual T4 landings of stout whiting averaged about 713 t for the fishing years 2013–2015, with a maximum harvest in the last 10 fishing years of 1140 t and a maximum historical harvest of 2400 t in the 1995. Stout whiting catch rates from both Queensland and New South Wales were analysed for all vessels, areas and fishing gears. The 2015 catch rate index was equal to 0.85, down 15% compared to the 2010–2015 fishing year average (reference point =1). The stout whiting fish length and otolith weight frequencies indicated larger and older fish in the calendar year 2014. This data was translated to show improved measures of fish survival at about 38% per year and near the reference point of about 41%. Together, the stout whiting catch rate and survival indicators show the fishery was sustainable. Earlier population modelling conducted for the year 2013 also suggested the stock was sustainable, but the estimate was only marginally above the biomass for maximum sustainable yield. Irrespective, reasons for reduced catch rates should be examined further and interpreted with precaution, particularly given the TACC has been under-caught in many years. For setting of the 2016 TACC, alternate analyses and reference points were compared to address data uncertainties and provide options for quota change. The results were dependent on the stock indicator and harvest procedure used. Uncertainty in all TACC estimates should be considered as they were sensitive to the data inputs and assumptions. For the 2016 T4 fishing year, upper levels of harvest should be limited to 1000–1100 t following procedure equation 1, with target levels of harvest at 750–850 t for procedure equation 2. Use of these estimates to set TACC will depend on management and industry intentions.

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The fisheries resources of Kyoga basin lakes are of greater socio-Economic significance for the poor rural communities of this area. The lake's fisheries provide the much needed animal protein as well as source of income for the fishers and the rural poor communities. Nationally, Kyoga basin lakes fisheries are economically important in that they contribute 27% of the total national fish production. In addition, more than 15 riparian districts depend on it for food and income. Moreover, fish from lakes Kyoga and Kwania playa major role in the regional export commodity trade earning the country foreign exchange. The perception that heavy exploitation of inland fishery resources threatens a loss of socio-economic benefits to local communities and their governments has prompted the new ways of management.

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Sea cucumber stocks have been overfished in many countries. As a consequence, several species (Holothuria polii, Holothuria tubulosa and Holothuria mammata) are now caught in Turkish waters without adequate knowledge on their biology and ecology. Here, we address their morphometry, relationships among gutted length and weight, population dynamics, temporal evolution of catches, and we provide the first insights about technical aspects of their fisheries. The largest size classes of H. polii are missing from our sampling collection, possibly due to the heavy fishery pressure on this species. Significant differences in the eviscerated length and weight were found among the Turkish sampled localities for H. polii and H. tubulosa, respectively. These differences could be explained by higher food availability in some areas and/or differential fishery pressure. The size and weight of H. tubulosa specimens were smaller than those registered for the same species in Greek waters, where this species is not fished. All the studied species showed allometric growth. In the last two years, the sea cucumber fishery in Turkey has been increasing rapidly, reaching a total production of ca. 555 000 kg in 2012 (80% H. polii and 20% H. tubulosa plus H. mammata). For a correct management of these species, we recommend: 1) the reestablishment of species-specific closed fishery season according to the specific reproductive cycle; 2) the assessment of the exploited stocks from the Northern Turkish coasts with estimates of recovery time of their populations; 3) the reduction of fishery efforts, mainly on H. polii and H. tubulosa and 4) the establishment of protected areas (where sea cucumber fisheries are forbidden) to conserve healthy populations which will favour the recruitment on nearby areas.

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A prototype for a Responsive Fisheries Management System (RFMS) was developed in the context of the European FP7 project EcoFishMan and tested on the Portuguese crustacean trawl fishery. Building on Results Based Management principles, RFMS involves the definition of specific and measurable objectives for a fishery by the relevant authorities but allows resource users the freedom to find ways to achieve the objectives and to provide adequate documentation. Taking into account the main goals of the new Common Fisheries Policy, such as sustainable utilization of the resources, end of discards and unwanted catches, a management plan for the Portuguese crustacean trawl fishery was developed in cooperation with the fishing industry, following the process and design laid out in the RFMS concept. The plan considers biological, social and economic goals and assigns a responsibility for increased data collection to the resource users. The performance of the plan with regard to selected indicators was evaluated through simulations. In this paper the process towards a RFMS is described and the lessons learnt from the interaction with stakeholders in the development of an alternative management plan are discussed. (C) 2014 Elsevier Ltd. All rights reserved.

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Information on marine and estuarine capture fishery activity in northern Todos os Santos Bay, northeastern Brazil, based on daily data collected between September 2003 and June 2005 is presented. Small-scale artisanal fishery in this area includes the use of traditional vessels both nonmotorized and motorized for locomotion, being carried out mainly by canoe or on foot, and involves many different kinds of gear, including gillnet, hook and line, seine nets, and traps. A total of 113 taxa were grouped into 77 resources, including 88 fish, 10 crustaceans, and 15 mollusks. Data on nominal catches of fish, crustaceans and mollusks are presented by month and location. A total of 345.2 tonnes of fishery resources were produced (285.4 tonnes of fish, 39.2 tonnes of fresh invertebrates, and 20.6 tonnes of processed invertebrates). Temporal variation in the fish catch was associated with the life cycle of the species or with the hydrographic conditions. The first-sale value of this catch amounted to around US$ 615,000.00, fishes representing 71.3% of it. A table of the average price of each fishery resource is presented. The results produced in this study may be considered a reference for future monitoring programs of fishery resources in the area.

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Through the assessment of three decades of the Alcohol Program in Brazil, the paper shows that adequate public policies regarding biomass production can deliver direct benefits like energy security improvement, foreign exchange savings, and local employment generation, reduced urban air pollution and avoided CO(2) emissions. Moreover, the paper shows that Brazilian produced ethanol has faced economies of scale, technical progress and productivity gains and is no longer dependent on subsidies to be competitive. The paper also examines the potential in Brazil for fostering other biofuels, namely biodiesel obtained from vegetable oils, as well as their implications on sustainable energy development. (C) 2011 Elsevier Ltd. All rights reserved.

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There is more to sustainable forest management than reduced impact logging. Partnerships between multiple actors are needed in order to create the institutional context for good forest governance and sustainable forest management and stimulate the necessary local community involvement. The idea behind this is that the parties would be able to achieve more jointly than on their own by combining assets, knowledge, skills and political power of actors at different levels of scale. This article aims to demonstrate by example the nature and variety of forest-related partnerships in Brazilian Amazonia. Based on the lessons learned from these cases and the authors` experience, the principal characteristics of successful partnerships are described, with a focus on political and socioeconomic aspects. These characteristics include fairly negotiated partnership objectives, the active involvement of the public sector as well as impartial brokers, equitable and cost-effective institutional arrangements, sufficient and equitably shared benefits for all the parties involved, addressing socioeconomic drawbacks, and taking measures to maintain sustainable exploitation levels. The authors argue that, in addition to product-oriented partnerships which focus on sustainable forest management, there is also a need for politically oriented partnerships based on civil society coalitions. The watchdog function of these politically oriented partnerships, their awareness-raising campaigns regarding detrimental policies and practices, and advocacy for good forest governance are essential for the creation of the appropriate legal and political framework for sustainable forest management. (C) 2008 Elsevier B.V. All rights reserved.

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The aim of this article is to present the main contributions of human resource management to develop sustainable organizations. The relationship between human resources and organizational sustainability, which is based on economical, social and environmental performance, involves some important aspects concerning management such as innovation, cultural diversity and the environment. The integration of items from the triple bottom line approach leads to developing a model based on a strategic and central posture of human resource management. Based on this model, propositions and recommendations for future research on this theme are presented.