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1.
With the development of the ecosystem approach to fisheries, improving fishing selectivity has increasingly been put forward as an objective for management. The aim of this paper is to clarify the limits of fishing selectivity and its use in fisheries management. Fishing selectivity would be better apprehended if restricted to the catching process only, not to the utilisation that is made of the catch once onboard, which falls under catch utilisation. Confusion would be further limited if fishing selectivity is restricted to the fishing operation scale, while exploitation pattern, i.e. the distribution of fishing mortality at the population or community level, applies to larger scales. Fishing selectively is minimizing bycatch – catching primarily the fishing trip targets. Since the ecological consequences of maximising the target catch relative to bycatch remain unknown at integrated scales, fishing selectivity cannot be used as an objective in itself. However, its small scale, high manageability and good understanding make it a convenient instrument to reach management objectives at large scales. Selectivity can serve to manage what is extracted from the ecosystem and thus what can be used, and/or to manage what is left in the ecosystem and how fishing impacts it. Different factors affect fishing selectivity, catch utilisation and exploitation patterns, some of them are manageable and thus can be used to move towards these objectives. Management tools are diverse, but need to be integrated to meet large-scale objectives. The complexity of dealing with large scales incurs a need to develop the available knowledge on exploitation patterns and catch utilisation to be able to adequately manage and monitor progress toward selectivity-related objectives.  相似文献   

2.
Maximising the long term average catch of single stock fisheries as prescribed by the globally-legislated MSY objective is unlikely to ensure ecosystem, economic, social and governance sustainability unless an effort is made to explicitly include these considerations. We investigated how objectives to be maximised can be combined with sustainability constraints aiming specifically at one or more of these four sustainability pillars. The study was conducted as a three-year interactive process involving 290 participating science, industry, NGO and management representatives from six different European regions. Economic considerations and inclusive governance were generally preferred as the key objectives to be maximised in complex fisheries, recognising that ecosystem, social and governance constraints are also key aspects of sustainability in all regions. Relative preferences differed between regions and cases but were similar across a series of workshops, different levels of information provided and the form of elicitation methods used as long as major shifts in context or stakeholder composition did not occur. Maximising inclusiveness in governance, particularly the inclusiveness of affected stakeholders, was highly preferred by participants across the project. This suggests that advice incorporating flexibility in the interpretation of objectives to leave room for meaningful inclusiveness in decision-making processes is likely to be a prerequisite for stakeholder buy-in to management decisions.  相似文献   

3.
A large gap has been identified between the current and optimal economic performance of wild-capture commercial fisheries in Australia. Economic approaches have the potential to assist fisheries to bridge this gap, such as bio-economic models that combine biology with fishing costs to evaluate the economic performance of a broad range of management measures. Economic objectives are prevalent in overarching Australian fisheries legislation, however economic data is often not collected and economic analyses or instruments not broadly applied. This paper reviews selected Australian fisheries to demonstrate the accrued economic benefits from applying formal bio-economic models and conducting empirical analyses of the impact of supply on product value. Challenges to the implementation and continued use of economic analyses and instruments are discussed including: (i) short-term transition costs and associated trade-offs between ecological, economic, social and political objectives; (ii) scarce logistical and financial capacity to collect and analyse economic data; (iii) a lack of desire among industry to change and transition to economic targets such as maximum economic yield (MEY), particularly when it is associated with lower catches; and (iv) a lack of economic literacy among fisheries managers and industry. It is contended that many of these challenges initially arise from an absence of clearly identified and prioritised objectives within overarching legislation and management plans. Once objectives are prioritised, limited resources can be allocated more efficiently to improve data collection, economic analysis and increase awareness as well as education of managers and industry.  相似文献   

4.
Integrative approaches that involve natural and social scientists are needed to manage fisheries, but these are difficult to achieve. The process of developing a prototype, knowledge-based, electronic decision support tool for the South African sardine Sardinops sagax fishery provided a platform for fostering collaboration and achieving active participation of many stakeholders. The aim of the decision support tool is to assist managers in evaluating how effectively an ecosystem approach to fisheries (EAF) has been implemented for this fishery. The collaborative process involved a series of meetings during which knowledge was elicited from fisheries scientists, social scientists, resource managers and fishing industry representatives. Conceptualisations of the different stakeholder perspectives were developed in terms of objectives and indicators following the hierarchical tree approach recommended by FAO. This paper describes the collaborative process. Hierarchies of objectives, indicators and data sets for the human dimension of an EAF in the South African sardine fishery are introduced. The value of a transdisciplinary approach towards an EAF in South Africa is discussed.  相似文献   

5.
Q methodology provides a novel, quantitative approach to reveal stakeholder perspectives and was used to assess social acceptance of Marine Protected Areas (MPAs) with fisheries and conservation management goals using the Devon & Severn region, UK as a case study site. Participants sorted a set of statements (n=42) into a forced-choice frequency distribution and centroid analysis revealed three factors for interpretation: (1) ‘pro-conservation’, characterised by views that conservation should be prioritised over commercial and economic interests; (2) ‘pro-fisheries’ who saw fishing as the priority and expressed concerns over the uncertainty of management measures and the number of planned MPAs; and (3) ‘win–win’ who felt that the current approach to marine management using MPAs would allow both fisheries and conservation goals to be met. Despite some differences in opinion, social acceptability of MPAs was identified across all three discourses, but was limited by the knock-on effects of the exclusion of stakeholders from the implementation of MPAs and the development of management measures. This resulted in disenfranchisement and uncertainty over the future of their activities. The results suggest that social acceptability of MPAs is generated by effective and ongoing stakeholder engagement, transparency and honesty relating to the costs and benefits of designations and a certainty that once sites are in place the resources exist for their effective management. Understanding social acceptability will guide adaptive management and increase the chances of MPA success and the meeting of global targets.  相似文献   

6.
The ecosystem approach to fisheries (EAF) is a holistic paradigm that considers stocks of exploitable species, marine ecosystems and stakeholders. Management agencies must strike a balance between their capacity constraints and the requisites of management measures. Most small-scale sea cucumber fisheries of Pacific Islands have been plundered while others are being opened to commercial exploitation. Data from fishery managers and a regional workshop were used to assess the current problems, institutional constraints and solutions to the management of sea cucumber fisheries in 13 Pacific Island countries (PICs). Technical capacity was often strong for some management actions such as developing marine reserves but weak for others, such as enforcement. Using multi-disciplinary indicators, half of the fisheries were diagnosed by their managers as being overfished or depleted, despite evidence of optimistic bias. Fishery governance varied greatly among the PICs, and co-management frameworks were not typical of any cultural region. Management objectives were prioritised differently among managers but most highly ranked was to protect ecological resilience. The fishery managers proposed different sets of regulatory measures and various management actions, such as surveys to collect socio-economic and fishery-dependent data, support for local governance and strong enforcement – all widely under-practised. Pacific sea cucumber fisheries exemplify how the transition to an EAF by management institutions must involve reorganisation of their technical and human-resource capacities among management tasks. Levies on exports need to be internalised to fund improved management. Management agencies should consider a shift in resources from developing marine reserves, conducting underwater surveys and aquaculture-based restocking to strengthening enforcement capacity, stakeholder involvement and communication with fishers. In concert with these actions, short fishing seasons, shortlists of allowable species and tighter enforcement at export points may serve to turn the tide on boom-and-bust exploitation and safeguard biodiversity.  相似文献   

7.
The basic structure of the fishing industry in the United Kingdom is outlined, followed by a discussion focusing on six stages of development from the industrial revolution to the present. The industrial focus is evaluated with regard to the catching and shore sides of the industry respectively. The management system is discussed in terms of stakeholder groups, the fisheries resource and marine ecosystem, and regional management. It is concluded that a regional management system closely adjusted to the regional geography of the industry will be most effective.  相似文献   

8.
This study examined the use of Individual Transferable Quotas (ITQs) to effectively manage fishing impacts on all ecosystem components, as required under Ecosystem Based Fisheries Management (EBFM) principles. A consequence of changing from input controls to output-based (catch) management is that the control of the regulating authority tends to be reduced, which may affect the outcomes for ecosystem management. This study reviewed the use of input controls across six fishing methods in 18 ITQ fisheries, which have been independently accredited as ecologically sustainable by the Marine Stewardship Council (12 fisheries) or under Australian environmental legislation for Wildlife Trade Operation (six fisheries). Input controls were retained across a range of ITQ fisheries, with non-selective fisheries such as trawl, gillnet and line employing more input controls than selective fisheries such as purse-seine, pot/trap and dredge. Further case-studies confirmed the widespread and recent use of input controls (spatial and temporal closures) with the aim of managing ecosystem impacts of fishing. The retention of input controls, particularly closures affects the security (quality of title) characteristic of the fishing use right and the theoretical ability of fishers to manage their right for their future benefit. The security characteristic is weakened by closures through loss of access, which undermines industry trust and incentive for long-term decision making. By reducing the security of ITQs, individual fisher incentives and behaviour may separate from societal objectives for sustainability, which was one of the foremost reasons for introducing ITQ management.  相似文献   

9.
The Gulf of Gabes located in southern Tunisia is one of the most productive ecosystems in the Mediterranean Sea. Despite its ecological importance, it is subject to high fishing pressure affecting the different components of the ecosystem. Given the multispecies, multigear nature of the fishery, there is a need to manage trade-offs between environmental and economic objectives. In this study, an Ecospace model was developed based on the previously constructed Ecopath model of the Gulf of Gabes and calibrated for the period 1995–2008 to investigate the response of the ecosystem to a set of alternative spatial management scenarios. These scenarios were derived from the current fishery regulation owing the important interest expressed by local fishery managers to assess new management measures. The results showed for each management scenario how bottom trawling and coastal fishing impact the different trophic groups and the complexity of interaction between these two fishing activities. Furthermore, spatially explicit simulations were performed to identify regions where the management measures are effective. Results suggested that for some trophic groups, these regions are well-defined which would be interesting to propose more accurate spatial measures. Finally, several indicators were calculated to evaluate the proposed management plans and provide managers with a straightforward set of decision rules to describe the potential trade-offs and fulfill both fisheries and conservation management objectives in the context of an ecosystem approach. The decision rules were based on observed trends to reduce uncertainty relative to the model complexity and provide consistent advice to decision-makers.  相似文献   

10.
China is the world's largest country in terms of fish production, yet its fisheries management is comparatively unknown outside the country. This article gives an overview of the current management system and highlights some of its challenges. In the past 30 years, the Department of Fishery Administration has formulated and organized a series of conservation and management regimes and measures. The most important tools are minimum mesh size regulation and a range of input control measures, including seasonal closures and attempts to control fishing capacity through licensing and limiting total engine power. However, fisheries output is only controlled through a nation-wide total catch limit. Certain progress has been achieved, but there are still problems as the resource situation is poor. While the existing measures could, in principle, improve sustainability, their enforcement is insufficient, and they do not limit fishing effort in a way that would allow recovery.  相似文献   

11.
地学在近海渔业管理中的应用虽是个刚刚兴起的研究领域,但已向人们展示了它令人振奋的成果。通过分析地学成果的获取、表达及地球物理技术的进展情况,介绍了加拿大地学专家如何成功地将地学成果应用于指导近海渔业捕捞,以及如何利用地学知识评价不同捕捞器材对环境的影响。  相似文献   

12.
The current fisheries management regime in New Zealand involves a system of quota management within which individual quotas are owned by fishermen and are transferable on an open market. The sum of these individual transferable quotas ITQs for a particular species equates to the total allowable catch TAC for that species. The objectives, implementation and consequences of this system are outlined, and its significance for stock assessment for species included in the ITQ system is discussed. A recent need for a TAC reduction in the deep-water fishery for orange roughy Hoplostethus atlanticus is mentioned in the context of the ITQ system. It is suggested that there is potential for economic benefit to the fishing industry in the Benguela system if an ITQ system were to be introduced locally.  相似文献   

13.
As a contribution to South Africa's move towards an ecosystem approach to fisheries management, this study explores the existence of common perceptions about South Africa's pelagic fishery between resource users and scientists. It represents a collaborative research effort of social and natural scientists. A brief overview is given of the southern Benguela upwelling ecosystem and small pelagic fish resources, the fishery, and management of the fishery. Stakeholder knowledge and views were determined by conducting open-ended qualitative local knowledge interviews. Candidate indicators to address five major issues raised in the interviews were selected: length-at-50% maturity, total mortality, exploitation rate, proportion of bycatch, mean length of catch, and centre of gravity of catches. The indicator approach is shown to be a useful tool to manage the South African small pelagic fishery, and can be made compatible with existing management approaches. The foundation of a good adaptive fisheries management system is a data collection system that enables multi-disciplinary analysis and provides a basis on which decisions can be made.  相似文献   

14.
The Tasmanian rock lobster industry has been managed by Individually Transferable Quotas (ITQs) and several input control measures since 1998. In this study, nine years of rock lobster fishing business data were used to categorise the catch and quota ownership traits and examine the response to the introduction of ITQ management. More specifically the study investigates how profit drivers moderated industry structure change.  相似文献   

15.
The reduction of discards in European fisheries has been identified as a specific objective of the reform of the EU Common Fisheries Policy. To reduce the uncertainty in catch data and the socially unacceptable waste of resources that results from the disposal of catch at sea, a policy to ban discards has been proposed. Discard bans are currently implemented in Alaska, British Columbia, New Zealand, the Faroe Islands, Norway and Iceland. Experience from these countries highlights that a policy of mandatory landings can result in a reduction in discards, but relies upon a high level of surveillance or economic incentives to encourage fishers to land more of their catch. Discard bans will also not result in long term benefits to stocks unless total removals are reduced, through the avoidance of undersized, non-commercial or over quota catch. Experience shows that additional management measures are required to incentivise such a move towards more selective fishing. Success has resulted from the use of area closures and bycatch limits, with potential applications in EU fisheries. However, selective fishing will not be a panacea for the current state of European fisheries; discard bans and accompanying measures must be embedded in a wider management system that constrains fishing mortality to reasonable levels before sustainable exploitation can occur.  相似文献   

16.
The performance of the EU long-term management plan for cod stocks, in force since 2009, is analysed focusing on the human and institutional factors. The plan operates through landings quotas (TACs) and effort restrictions following a Harvest Control Rule, and deploys a novel instrument allowing Member States to ‘buy back’ or increase fishing effort for fleet segments engaged in cod-avoidance measures. The stipulated fishing mortality reductions have not been achieved. On the positive side, the ‘buy-back’ instrument has led to increased uptake of selective gear and implementation of permanent and real-time temporary closures. On the negative side, ignoring the dimension of fishers as reactive agents in the design, the impact assessment, and the annual implementation of the measures has contributed to the failure to adequately implement the plan and achieve its objectives. The main problem is that the landings quotas taken in a mixed fishery did not limit catches because fishers were incentivised to continue fishing and discard overquota catch while quota for other species was available. The effort limitations intended to reduce this effect were insufficient to adequately limit fishing mortality in targeted fisheries, although fishers experienced them as prohibiting the full uptake of other quotas. Recommendations for future plans include (i) management through catch rather than landings quotas, (ii) the internalisation of the costs of exceeding quotas, (iii) use of more selective gear types, (iv) the development of appropriate metrics as a basis for regulatory measures and for evaluations, (v) participatory governance, (vi) fishery-based management, (vii) flexibility in fishing strategy at vessel level.  相似文献   

17.
California sea lions (Zalophus californianus) off the coast of Southern California are known to damage both commercial and recreational fishing activities, causing decreases to fish catch and damage to gear. Their increasing population has intensified the potential for conflict between sea lions and anglers, likely requiring changes to current legislation. The recreational fishing community in Southern California is a valuable and largely underutilized source for information and potential solutions to management and legislative problems. This recreational fishing survey-based study conducted in 2013 utilized personal interviews, conducted in the field with recreational anglers and commercial passenger fishing vessel (CPFV) crews in Southern California, to gather data on: (a) the occurrence and impact of sea lion depredation on the local fishing, (b) angler awareness and opinions on current legislation, and (c) the conflict between fishing activities and conservation efforts. Results show that surveyed CPFV operators and private boaters had the most conflict with sea lions and perceive them as more of a problem than anglers on piers, jetties or kayaks. The conflict was also reportedly more prevalent in San Diego County compared to the other counties surveyed (Orange, Los Angeles and Ventura). Participating CPFV operators were overwhelmingly in support of a government culling program for sea lions, while recreational angler respondents did not feel that a control program was necessary. These CPFV operators reported more money lost, and were willing to pay more for an effective deterrent device. There was also a consensus among respondents that fish catch is declining, yet anglers were unsatisfied with the effectiveness of current legislation designed to increase fish stocks. These data will provide a better understanding of California sea lion depredation in Southern California and its effect on recreational anglers in order to aid future mitigation efforts. Additionally, these results provide stakeholder feedback on local marine protected areas and other fisheries management legislation, and build a foundation for future conservation and education programs.  相似文献   

18.
This study employs Structural Equation Models (SEMs) to systematically analyze the components of a multi-stakeholder negotiation in an applied setting. It characterizes participant perceptions of a multi-stakeholder, consensus-based negotiation process used to reduce harmful interactions between marine mammals and fishing gear in U.S. waters (marine mammal Take Reduction Teams). From April to July 2013, 234 current and former participants of eight Take Reduction Teams received a survey with 15 questions about the negotiation process, outputs (Take Reduction Plans), and outcomes. The SEMs depict relationships among the latent variables of social capital and shared learning, fairness, stakeholder satisfaction with the Take Reduction Plans, and their perceived outcomes. The SEMs also explain the influence of independent predictors of team identity and age, geographic region, and stakeholder affiliation on the latent variables. Results indicate that stakeholder views of fairness significantly influenced their satisfaction with the Take Reduction Plans, which in turn, significantly affected their opinions of the outcomes. While the majority of participants believed the plans were at least slightly successful at reducing marine mammal bycatch, this varied among teams and was significantly influenced by stakeholder affiliation, region, and Take Reduction Team age.  相似文献   

19.
史磊  宋毅宁  秦宏 《海洋科学》2021,45(4):40-50
自20世纪80年代以来,我国出台了众多海洋捕捞相关政策,厘清这些政策变迁规律对海洋捕捞业的健康发展具有重要意义。本文对1986年以来我国海洋捕捞业的政策文本展开量化分析,构建政策时间维度、政策工具维度、政策价值维度三维政策文本分析框架,梳理当前捕捞业政策变迁和结构特征,并深入分析了捕捞业政策与现实的匹配性。研究发现,海洋捕捞业的部分政策目标之间存在一定的冲突和矛盾;政策工具体系全面,但不同政策工具数量分布不均衡;早期政策的经济价值取向突出,社会、生态价值相对不足,需要适时调整政策价值取向。未来应明确政策目标,推动海洋捕捞管理范式由投入控制向产出控制的转变;优化政策工具组合,引导渔民自觉养护海洋渔业资源,提高海洋捕捞业政策的有效性;整合政策价值取向,协调产业发展、资源养护和渔民利益的关系,推动海洋捕捞可持续发展。  相似文献   

20.
An assessment of management effectiveness of Kenya's oldest marine protected areas (Malindi and Watamu) was conducted within the framework of a regional assessment in Kenya, Seychelles and Tanzania. Biophysical, socio-economic and governance indicators were used to assess the delivery of MPA management objectives. Results indicate that the Malindi and Watamu marine parks that are no-take areas are making progress towards meeting their stated objective of biodiversity conservation. The 1997–1998 ENSO related bleaching event caused the greatest single measurable impact on the coral reefs of the marine parks leading to very high levels of coral mortality. The marine reserve where fishing is regulated was less effective in meeting its objective of sustaining community livelihoods. The weakest trends were related to the development of governance structures. A combination of management inefficiencies due to overlapping mandates, financial and administrative constraints, and inadequate stakeholder participation interacted to reduce the ability of the MPAs to fully achieve their objectives.  相似文献   

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