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1.
Although overexploitation of commercial fish stocks in European waters has been in the public debate now for more than 20 years, the European Union has so far failed to implement sustainable fisheries management. Millions in subsidies paid to the fishing industry have led to significant excess capacity in the fishing fleet. Various feeble attempts to stop overexploitation of marine resources have failed. The cause is that fishing policy is highly dominated by short-term socioeconomic interests. There is an urgent need for a new fisheries management system in Europe that supports reductions in the fishing fleet, increases responsibility among fishers and guarantees long-term conservation of natural marine resources.Transferable rights to fish have proved a reliable and effective means of creating incentives to conserve marine resources. By strengthening individual fishing rights under flexible quota management systems, the EU Member States could, within the Common Fisheries Policy, make a significant contribution to conserving fish stocks, to reducing excess capacity and to raising the profitability of the fisheries industry. A closer look at existing reservations against a flexible management system shows most of the objections to be overstated or capable of resolution.  相似文献   

2.
An important task of natural resource management is deciding amongst alternative policy options, including how interventions will affect the dynamics of resource exploitation. Yet predicting the behaviour of natural resource users in complex, changeable systems presents a significant challenge for managers. Scenario planning, which involves thinking creatively about how a socio-ecological system might develop under a set of possible futures, was used to explore uncertainties in the future of the Indian Ocean tuna purse seine fishery. This exercise stimulated thinking on how key social, economic and environmental conditions that influence fleet behaviour may change in the future, and how these changes might affect the dynamics of fishing effort. Three storylines were explored: an increase in marine protection, growing consumer preference for sustainable seafood, and depletion of tuna stocks. Comparing across several possible future scenarios, a number of critical aspects of fleet behaviour were identified that should be important considerations for fishery managers, but which are currently poorly understood. These included a switch in fishing practices, reallocation of effort in space, investment in new vessels and exit from the fishery. Recommendations for future management interventions in the Indian Ocean were offered, along with suggestions for research needed to reduce management uncertainty.  相似文献   

3.
4.
A Dutch pilot study of fully documented fisheries provided the opportunity to observe actual changes in fishing behaviour under catch quota management (CQM). Interviews with fishers in the pilot study aided in interpreting the results and giving insight in the decision making process and reasoning of fishers. The CQM pilot study entailed a fleet of small and large demersal vessels. For these vessels, all cod catches were counted against quota, including catches of individuals below minimum landings size. To obtain reliable catch data all vessels were equipped with electronic monitoring (EM) systems. These systems recorded videos of all fishing and processing activities on board. In return, fishers received a 30% quota bonus for cod and were compensated with more flexibility on effort regulations. It was hypothesized that vessels in the CQM will (i) increase their landings by 30% according to their quota bonus, (ii) increase the use of gear with large mesh size, and (iii) change effort towards fishing locations with high catch rates of large cod and avoid areas with high catch rates of undersized cod. The results showed that CQM had no effect on fishing behaviour of the small vessels. In contrast, large vessels significantly increased their cod landings (216%) and avoided undersized cod. This difference in response of different fleets suggested that implementation of CQM, for instance in the context of the European Common Fisheries Policy, should consider fleet characteristics. It seemed that larger vessels in this study more easily adapted their behaviour to new management regimes and that the quota bonus opened up new fishing strategies, that were not envisaged during the implementation.  相似文献   

5.
The European Union has established a framework to achieve or maintain good environmental status in the marine environment by 2020. The Marine Strategy Framework Directive requires the application of the ecosystem approach to the management of human activities, covering all sectors having an impact on the marine environment. However, fisheries in the Mediterranean are far from a systematic implementation of an ecosystem-based fisheries management (EBFM). Aiming to address this issue, this study explores the potential of the relationship between daily yield by vessel (landings and income by species) and vessel position (known via vessel monitoring system) as a tool for fleet management. This approach is possible due to the current dynamics of Mediterranean fleets, with vessels returning daily to the harbour where landings are registered as weight and income by vessel. Moreover, vessels of >15 m total length have been compulsory monitored by VMS since 2005. A bottom trawl fleet that operates in the northwestern Mediterranean was chosen to develop this approach. Different groups of trawlers were identified, which could be linked to the strategies displayed by the fishermen that were mainly driven by the target species dynamics. Accurate knowledge of the fishing targets driving the fleet dynamics and of the fishing strategies at the vessel level (i.e. fishing ground habitat where the fishing pressure is exerted and corresponding landings) are shown to be a feasible tool for fleet management.  相似文献   

6.
A challenge of managing data poor fisheries lies in overcoming uncertainties associated with a lack of information on biological and socio-economic conditions. This paper focuses on site prioritisation for marine protected areas, a process that usually imposes moderate to heavy demands on data, time, local expertise, and funds. A fuzzy logic decision support tool for zoning marine areas that is suitable for use in data poor conditions is developed. This tool, the Protected Area Suitability Index (PASI), assesses the suitability of sites for protection based on fishers’ preferences for that site and the site’s conservation value. Only eight input attributes are required to run the PASI, which operates on a series of heuristic rules to estimate a site suitability score that ranges from 0 to 10, where 10 indicates that a site is highly suitable for being protected from fishing. Sensitivity analysis reveals that the PASI is relatively robust, and produces reliable results even as the system is degraded by the loss of data. Eighteen actively fished sites and 11 sites that are closed to fishing are assessed to evaluate how well the PASI is able to distinguish differences between sites. The estimated scores are significantly different (p<0.05), whereby non-fished sites are scored as being more suitable for protection than fished sites. The PASI can be used as a decision support tool to facilitate systematic marine spatial management under data poor conditions, especially in the task of identifying suitable sites for protection.  相似文献   

7.
This paper develops a decision support tool that can help fishery authorities to forecast bivalve landings for the dredge fleet accounting for several contextual conditions. These include weather conditions, phytotoxins episodes, stock-biomass indicators per species and tourism levels. Vessel characteristics and fishing effort are also taken into account for the estimation of landings. The relationship between these factors and monthly quantities landed per vessel is explored using multiple linear regression models and data mining techniques (random forests, support vector machines and neural networks). The models are specified for different regions in the Portugal mainland (Northwest, Southwest and South) using six years of data 2010–2015). Results showed that the impact of the contextual factors varies between regions and also depends on the vessels target species. The data mining techniques, namely the random forests, proved to be a robust decision support tool in this context, outperforming the predictive performance of the most popular technique used in this context, i.e. linear regression.  相似文献   

8.
The pelagic species is closely related to the marine environmental factors, and establishment of forecasting model of fishing ground with high accuracy is an important content for pelagic fishery. The chub mackerel(Scomber japonicus) in the Yellow Sea and East China Sea is an important fishing target for Chinese lighting purse seine fishery. Based on the fishery data from China's mainland large-type lighting purse seine fishery for chub mackerel during the period of 2003 to 2010 and the environmental data including sea surface temperature(SST), gradient of the sea surface temperature(GSST), sea surface height(SSH) and geostrophic velocity(GV), we attempt to establish one new forecasting model of fishing ground based on boosted regression trees. In this study, the fishing areas with fishing effort is considered as one fishing ground, and the areas with no fishing ground are randomly selected from a background field, in which the fishing areas have no records in the logbooks. The performance of the forecasting model of fishing ground is evaluated with the testing data from the actual fishing data in 2011. The results show that the forecasting model of fishing ground has a high prediction performance, and the area under receiver operating curve(AUC) attains 0.897. The predicted fishing grounds are coincided with the actual fishing locations in 2011, and the movement route is also the same as the shift of fishing vessels, which indicates that this forecasting model based on the boosted regression trees can be used to effectively forecast the fishing ground of chub mackerel in the Yellow Sea and East China Sea.  相似文献   

9.
Commercial fishing data were used to reconstruct historical spatio-temporal patterns of fishing effort and landings in the bottom longline fishery of the Azores. Key events during an important 15-year period were charted, through fisher interviews together with GIS analysis. While effort distribution varied over time, the prevailing pattern was a shift in focus from eastern to western areas and from shelf/slope to offshore banks and seamounts in response to policy measures (e.g. banning bottom longline inside 3 NM, public aids for modernization of the fleet) and reduced fishing yields. Areas 12–50 NM from shore represented the most vital fishing grounds in terms of fishing effort and production. Declining landings of the major demersal species, in recent years, indicate that present catch levels are not sustainable and further measures need to be taken in order to sustain fisheries resources. Knowledge of fleet behavior and the distribution of fishing effort, particularly in patchy environments, provide valuable insights into the impacts of past management decisions and help predict the outcome of new policies both in this region and elsewhere.  相似文献   

10.
The Galapagos Islands are a prime example of a place where fishery management policies have been established without first understanding the behavior of fishermen. Since the creation of the Galapagos Marine Reserve in 1998, there has not been a single study in the archipelago that investigates fishing behavior and the factors affecting this behavior. This paper addresses this gap in the literature by describing and analyzing the decisions of the fishing fleet for the red spiny lobster fishery. It focuses on factors that affect the short-term decisions regarding both participation and intensity of participation in the lobster fishery. This paper finds that the fishing fleet in the Galapagos Islands behaves as profit maximizing firms, because they consider all the benefits and costs that affect both their participation decision as well as their decision about how frequently to be active after they have decided to participate. The results also show that there is a large latent effort in the lobster fisheries that could threaten the sustainability of any initiatives aimed at increasing catchability, prices, or markets. It is expected that this analysis will be valuable to policy makers when designing or improving the management plans for Galapagos fisheries.  相似文献   

11.
Declining catches are typically taken to be a warning sign of overfishing. But in fact, many such declines have been driven by recruitment changes unrelated to stock size, as evidenced by the failure of stocks to recover after reduction in fishing or recovery despite the failure to reduce fishing. Given a declining pattern, supposedly precautionary decisions to reduce fishing should be treated as experimental management options with a high probability of not resulting in the desired recovery to more productive stock sizes. Simple decision tables can be used to compare such experimental options to “wait and see” options that do not involve fishing reductions. A case example with a grouper fishery in Kuwait demonstrates that experimental effort reduction may not be the best policy from a decision analysis perspective, at least when there are substantial reasons to expect recruitment changes unrelated to stock size. In this case, virtual population analysis and stock reduction analysis models indicate either unusually weak recruitment compensation (steepness h < 0.4) or progressive decline in recruitment carrying capacity, possibly caused by decreases in estuarine rearing habitat associated with declining flows of the Tigris and Euphrates Rivers.  相似文献   

12.
The aim of this paper is to compare the criteria for eco-labeling of wild-caught fish in the Norwegian eco-certified fisheries, and to study if these eco-labels affect the harvesting patterns of Norwegian fishermen. The eco-labels Marine Stewardship Council (MSC), KRAV and Friend of the Sea (FOS) as applied in 2009 were studied. In this study, the harvesting patterns are defined by using the following parameters: season, catch area, size of fishing vessel, gear type, bycatch, location of landing site and distance to the fishing ground. KRAV had more specific criteria than did MSC and FOS in specific fisheries regarding time of the fishing effort, catch area, size of fishing vessels, gear type (e.g. hook size, and the use of beam trawlers was not permitted) and distance to the fishing ground. The findings show that few of the eco-label requirements influenced these aspects in Norwegian fisheries.  相似文献   

13.
An economic survey of the commercial operators currently active in the Queensland Coral Reef Fin-Fish Fishery has been carried out, as part of a research project aimed at evaluating alternative management options for this fishery. This paper presents the background analysis used as a basis to develop the sampling design for this survey. The background analysis focuses on activity patterns of the fleet based on effort and catch information, as well as patterns of quota ownership. Based on this information, a fishing business profile describing the micro-economic structure of fishing operations is developed. This profile, in conjunction with the qualitative information gained in undertaking the economic surveys, allows preliminary understanding of the key drivers of profitability in the CRFFF, and possible impacts of external factors on fishing operations.  相似文献   

14.
The management of fishing capacity—in both inland and marine fisheries—is a major policy concern in most countries in Southeast Asia. Excess capacity leads to a number of negative impacts, such as resource use conflicts, overfishing, environmental degradation, economic wastage, and security threats. This paper presents the results of a regional study that examined various approaches to managing excess fishing capacity in small-scale fisheries in Southeast Asia. More specifically, the paper presents an analysis of perceptions of stakeholders in Cambodia, Philippines and Thailand regarding preferred solutions to addressing excess capacity. The paper concludes with a discussion of policy guidance for addressing excess fishing capacity based on the stakeholder-preferred solutions.  相似文献   

15.
The science and management of marine resources is increasingly grappling with the use of ecosystem-based fisheries management. Though ecosystem-based fisheries management seeks to unite biological and sociocultural concerns into a holistic framework, people are often seen simply as external drivers of change. The technical questions that are often posed, such as the delineation of boundaries or the strategies of governance, are however more broadly questions concerning the social production of nature. This paper explores these issues by analyzing both the spatial fishing practices of different fishermen and the results of a series of workshops held in New England to solicit opinions about ecosystem-based fisheries management. The paper emphasizes teasing apart the human dimensions of fishing embedded in predominant notions such as fishing effort through more explicit consideration of spatially based resource dependencies and mutual constitution of society-nature.  相似文献   

16.
Many coastal communities have strong links to fishing that span generations where fishing is a way of life that goes beyond the means to earning a living. Fishing's influence is not confined to those activities that take place at sea, but spills over onto land to create a particular identity and sense of place in coastal towns inherently linked to fishing. Using Hastings in south-east England, with Britain's largest beach-launched fleet, as a case study, this paper considers how marine fishing contributes to place-making. Through an examination of the physical environment and semi-structured interviews, the study found that fishers have deep attachments to the fishing beach, called the Stade, which also defines their identity as individuals and as a fishing community. Non-fishers also value the contribution that fishing makes to the character of the town and its importance for related industries such as tourism. A deeper understanding of the attachments that fishers and non-fishers form with fishing places is needed to inform both local planning and regeneration strategies and, more broadly, fisheries and marine policy.  相似文献   

17.
As marine protected areas (MPAs) continue to be established, measures to address displaced effort are likely to become increasingly relevant. Recent experiences of displaced fishing effort programs for MPAs and recreational fishing reserves in Australia, together with two examples from the United States, are described. A practical framework for addressing displaced fishing effort is developed, which explores the likely displaced-effort scenarios and options when planning spatial commercial fishing closures for an MPA.  相似文献   

18.
The California Commercial Passenger Fishing Vessel (CPFV) fleet is unique in scale of operation, extensive fishing history, and economic impacts. The basses (Paralabrax sp.), which represent a principal target for the CPFV fleet, recently gained more stringent size limits and bag limits. The goal of this study was to conduct a survey of CPFV captains to assess perceptions regarding the status of two Paralabrax species, as well as the impacts of the new regulations. Catch and effort estimates were also obtained using CPFV logbook data to compare captains’ perceptions with actual changes in the fishery. The captains agreed that both species are vital to recreational fishing, and that the Barred Sand Bass stock is less healthy than Kelp Bass. Catch and effort analyses were consistent with this perception, with more dramatic declines in CPUE exhibited by Barred Sand Bass. The most experienced captains perceived the status of each species to be in a less healthy state than the less experienced captains, suggesting that shifting baselines are occurring. Most of the captains thought the increased minimum size limits had the greatest short-term impact on the fishing experience. The CPFV logbook data summaries support this assertion, but Kelp Bass CPUE showed a trend reversal. In contrast, Barred Sand Bass CPUE has precipitously declined, and spawning aggregations have been absent since 2013. The agreement between captains’ perceptions and logbook analyses strengthens the overall findings, and suggests captains are a valuable resource for informing fisheries management, especially in future studies with data-limited stocks.  相似文献   

19.
为提高大西洋热带海域长鳍金枪鱼(Thunnus alalunga)渔场预报的准确率,对K最近邻(k nearest neighbor,KNN)、逻辑斯蒂回归(logistic regression,LR)、决策与分类树(classfication and regression tree,CART)、梯度提升决策树(gr...  相似文献   

20.
It is widely recognized that fishing states are obliged to exercise flag state responsibility over their vessels. In an attempt to become a responsible fishing actor, Taiwan has endeavored to manage its distant water fishing fleet in accordance with international fisheries management. However, the long-standing problems of illegal, unreported and unregulated (IUU) fishing, fish laundering, and fishing overcapacity, which remained unsolved during the 1990s and early 2000s, brought its management capability into doubt. Failure to address these problems undermined the credibility of all management measures and ultimately resulted in a recommendation adopted by International Commission for the Conservation of the Atlantic Tunas (ICCAT) in 2005. This recommendation significantly affected Taiwan's distant water fishing policy. This paper examines how Taiwan assimilated this outside force into its fishing policy as a new response to international fisheries management and how fishers perceived this response. It shows that Taiwan's efforts in controlling distant water fisheries marked a big change, specifically manifest in three noticeable actions - reducing excessive bigeye-targeted efforts, deterring IUU fishing, and strengthening fisheries management. The study advises that management of small tuna vessels be effectively exercised and recommends future actions on providing subsidies for fishers to partially offset costs incurred by rule compliance, streamlining their administrative work, enhancing communication with them, putting more enforcement and meaningful penalties in place. Finally, the study indicates the existence of an interaction in the international fisheries management scheme, potentially favoring Taiwan to bargain for fishing rights and a favorable status in the participation of regional fisheries management organizations (RFMOs) in the future if it continues to exercise effective control of distant water fisheries.  相似文献   

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