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1.
Large pelagic fishes are assessed and managed by tuna Regional Fisheries Management Organizations (tRFMOs). These organizations have been criticized for not meeting conservation objectives, which may relate to aspects of governance and management. No previous studies have systematically evaluated why management performance differs among tRFMOs and among stocks within each tRFMO. In this study, we collected data on the nature of research, management, enforcement and socioeconomics of management systems in the five principal tRFMOs of the world's oceans. We quantified influences of economic and fishery‐related factors on these management characteristics and examined how these factors vary among tRFMOs. We found that tRFMOs with a greater number of member countries, a greater economic dependency on tuna resources, a lower mean per capita gross domestic product, a greater number of fishing vessels and smaller vessels were associated with less intensive research, management and enforcement in these tuna fisheries. We also quantified the influence of specific management attributes and of biological, economic and fishery‐related factors on the trends and current status of large pelagic fish stocks in these regions. The most important factors correlated with trends and current stock status were external to the management systems, and included stock size, age at maturity, ex‐vessel price and economic dependency of countries on tuna fisheries. To improve the overall status of large pelagic fish stocks in the global high seas, more intensive data collection, research and management are needed in certain areas, especially in the Indian Ocean, and for certain stocks, especially non‐target species. 相似文献
2.
John C. Field ré E. Punt Richard D. Methot & Cynthia J. Thomson 《Fish and Fisheries》2006,7(4):284-302
Marine protected areas (MPAs) have been increasingly proposed, evaluated and implemented as management tools for achieving both fisheries and conservation objectives in aquatic ecosystems. However, there is a challenge associated with the application of MPAs in marine resource management with respect to the consequences to traditional systems of monitoring and managing fisheries resources. The place‐based paradigm of MPAs can complicate the population‐based paradigm of most fisheries stock assessments. In this review, we identify the potential complications that could result from both existing and future MPAs to the science and management systems currently in place for meeting conventional fisheries management objectives. The intent is not to evaluate the effects of implementing MPAs on fisheries yields, or even to consider the extent to which MPAs may achieve conservation oriented objectives, but rather to evaluate the consequences of MPA implementation on the ability to monitor and assess fishery resources consistent with existing methods and legislative mandates. Although examples are drawn primarily from groundfish fisheries on the West Coast of the USA, the lessons are broadly applicable to management systems worldwide, particularly those in which there exists the institutional infrastructure for managing resources based on quantitative assessments of resource status and productivity. 相似文献
3.
- We respond to criticism of our earlier paper where we report Australia‐wide declines in fisheries catches that parallel the declining trends in fish populations observed underwater, and we highlight concerns about the low levels of precaution applied when regulating fisheries catches using the avoidance of recruitment failure approach.
- Most fished species worldwide lack the data needed for accurate stock status assessments, and consequently exploitation of these species should be managed with high precaution.
- For the relatively few species and stocks with individually modelled assessments, the errors associated with model output are extremely large as a result of the multiplicity of confounding factors (including effects of changing climate, technological advances that increase catch efficiency, fisher behaviour, interactions with other species, and changes in habitat quality), and the compounding of error introduced by subjective assumptions in multiple parameter estimates. The magnitude of this assessment uncertainty appears to be rarely recognized and incorporated into management decisions.
- Given the difficulties in accurately predicting and managing fishing impacts, including species interactions across space and time, a well‐designed set of no‐take marine reserves is critically needed. Although not a universal panacea, an effective global network of marine reserves arguably represents the most efficient and publicly acceptable next step – in addition to greenhouse gas reduction – towards solving the unfolding global dilemma confronting fish populations and ocean ecosystems.
4.
5.
Richard M Hillary Ann L Preece Campbell R Davies Hiroyuki Kurota Osamu Sakai Tomoyuki Itoh Ana M Parma Doug S Butterworth James Ianelli Trevor A Branch 《Fish and Fisheries》2016,17(2):469-482
There is considerable international concern and scientific debate about the current state and future of tuna stocks worldwide and the capacity of Regional Fisheries Management Organisations to manage the associated fisheries effectively. In some cases, this concern has extended to predictions of imminent collapse with minimal chances of recovery, even under a commercial catch moratorium. As a viable alternative to a full fishery closure, the Commission for the Conservation of Southern Bluefin Tuna (CCSBT) has adopted a scientifically tested, adaptive rebuilding strategy for the depleted southern bluefin tuna (Thunnus maccoyii) stock. The management procedure (MP) adopted involves a harvest control rule that fully specifies the total allowable catch as a function of key indicators of stock status, adjusting future harvest levels every three years so as to meet the rebuilding targets agreed by CCSBT. It was chosen from a subset of candidate MPs selected following extensive simulation testing. This involved first selecting a wide range of plausible scenarios for stock status and input data, ranging from pessimistic to optimistic, against which the alternative candidate MPs were tested to ensure that they were robust to important uncertainties. This is the first time that a comprehensively evaluated MP has been adopted for an internationally managed tuna stock. Both the process and the outcomes have broad applicability to other internationally managed stocks. 相似文献
6.
近海是众多渔业生物的产卵场、育幼场和索饵场,也是优良渔场,支撑着我国海洋渔业资源的世代发生量和\"海上粮仓\"的可持续产出.近海渔业贡献了 80%～90%海洋捕捞产量,在保障水产品供给、增加渔民收入、促进沿海地区海洋经济发展等方面发挥了重要作用.新中国成立以来,以近海渔业资源为切入点,我国科研人员围绕\"海洋渔业资源开发与可持续利用\"的关键科技问题,系统开展了一系列渔业资源调查与评估、基础与应用基础研究、技术研发工作,取得了多项创新性成果,支撑了我国海洋渔业资源合理利用、科学养护与管理.渔业资源研究重点与渔业资源开发利用程度和渔业发展休戚相关,本文结合不同时期国家渔业发展战略,系统回顾了 1950 年代以来我国近海渔业资源研究 4 个发展阶段(起步—发展阶段、快速发展阶段、综合研究阶段和新发展阶段)的特点、研究重点、调查装备及平台建设情况等;梳理了我国在近海渔业资源数量变动与渔场探查、渔业资源高效开发利用、渔业资源调查评估技术研发、科学规范的水生生物资源养护体系形成和海洋生态系统动力学等研究进展和代表性成果,及其对我国近海渔业发展、管理与资源养护政策调整的支撑作用;明确了未来渔业资源研究要注重多学科研究和综合性调查,深入解析渔业生态系统结构与功能的机制和机理,结合经济、社会等因素研发新的渔业资源利用与管理模式,实现\"开发中保护,保护中开发\",支撑资源养护型近海捕捞业实施和渔业高质量发展. 相似文献
7.
Brian Klitgaard Hansen Dorte Bekkevold Lotte Worsøe Clausen Einar Eg Nielsen 《Fish and Fisheries》2018,19(5):751-768
Application of environmental DNA (eDNA) analysis has attracted the attention of researchers, advisors and managers of living marine resources and biodiversity. The apparent simplicity and cost‐effectiveness of eDNA analysis make it highly attractive as species distributions can be revealed from water samples. Further, species‐specific analyses indicate that eDNA concentrations correlate with biomass and abundance, suggesting the possibility for quantitative applications estimating abundance and biomass of specific organisms in marine ecosystems, such as for stock assessment. However, the path from detecting occurrence of an organism to quantitative estimates is long and indirect, not least as eDNA concentration depends on several physical, chemical and biological factors which influence its production, persistence and transport in marine ecosystems. Here, we provide an overview of basic principles in relation to eDNA analysis with potential for marine fisheries application. We describe fundamental processes governing eDNA generation, breakdown and transport and summarize current uncertainties about these processes. We describe five major challenges in relation to application in fisheries assessment, where there is immediate need for knowledge building in marine systems, and point to apparent weaknesses of eDNA compared to established marine fisheries monitoring methods. We provide an overview of emerging applications of interest to fisheries management and point to recent technological advances, which could improve analysis efficiency. We advise precaution against exaggerating the present scope for application of eDNA analysis in fisheries monitoring, but also argue that with informed insights into strengths and limitations, eDNA analysis can become an integrated tool in fisheries assessment and management. 相似文献
8.
Michael C. Melnychuk Charmane E. Ashbrook Richard J. Bell Lyall Bellquist Kate Kauer Jono R. Wilson Ray Hilborn Jay Odell 《Fish and Fisheries》2023,24(5):711-729
The status of federally managed fisheries in the United States is well monitored, but the condition of other marine fisheries, whether state-managed, territory-managed or unmanaged, is less understood and often unknown. We used expert surveys to characterize the management systems of non-federally managed fisheries in US coastal marine states and overseas territories. For 311 fisheries, we estimated an overall Fisheries Management Index (FMI) and a qualitative stock status score. These measures were positively correlated, and while a wide range of research, management, enforcement and socioeconomic criteria were partially met (FMI ≥ 0.5) for 66% of fisheries, stock status was considered as partially acceptable (score ≥ 0.5) for only 45% of fisheries and acceptable (score = 1) for only 16% of fisheries. Higher FMI was typically observed in fisheries with greater commercial landed weight, value, or greater recreational catches. Fisheries from continental states had higher FMI than those from overseas territories. Invertebrates and diadromous fish species had higher FMI on average compared to those of marine fishes. Extrapolating results for surveyed fisheries to nearly 2000 non-federally managed US fisheries while stratifying by state and importance designation (based on commercial, recreational, cultural or ecological importance), we estimate a mean overall FMI of 0.48, and estimate that only 19% of fisheries have a reliable estimate of stock status available; both measures are lower than similar estimates for federally managed fisheries. Funding or capacity constraints and information or data limitations were identified as common challenges faced by state agencies in managing fisheries under their jurisdiction. 相似文献
9.
近海是众多渔业生物的产卵场、育幼场和索饵场,也是优良渔场,支撑着我国海洋渔业资源的世代发生量和“海上粮仓”的可持续产出。近海渔业贡献了80%~90%海洋捕捞产量,在保障水产品供给、增加渔民收入、促进沿海地区海洋经济发展等方面发挥了重要作用。新中国成立以来,以近海渔业资源为切入点,我国科研人员围绕“海洋渔业资源开发与可持续利用”的关键科技问题,系统开展了一系列渔业资源调查与评估、基础与应用基础研究、技术研发工作,取得了多项创新性成果,支撑了我国海洋渔业资源合理利用、科学养护与管理。渔业资源研究重点与渔业资源开发利用程度和渔业发展休戚相关,本文结合不同时期国家渔业发展战略,系统回顾了1950年代以来我国近海渔业资源研究4个发展阶段 (起步—发展阶段、快速发展阶段、综合研究阶段和新发展阶段)的特点、研究重点、调查装备及平台建设情况等;梳理了我国在近海渔业资源数量变动与渔场探查、渔业资源高效开发利用、渔业资源调查评估技术研发、科学规范的水生生物资源养护体系形成和海洋生态系统动力学等研究进展和代表性成果,及其对我国近海渔业发展、管理与资源养护政策调整的支撑作用;明确了未来渔业资源研究要注重多学科研究和综合性调查,深入解析渔业生态系统结构与功能的机制和机理,结合经济、社会等因素研发新的渔业资源利用与管理模式,实现“开发中保护,保护中开发”,支撑资源养护型近海捕捞业实施和渔业高质量发展。 相似文献
10.
Julien Cucherousset Rémy Lassus Carsten Riepe Paul Millet Frédéric Santoul Robert Arlinghaus Mathieu Buoro 《Fisheries Management and Ecology》2021,28(4):295-304
Although freshwater fish stocking is widely used by managers, quantitative assessments of stocking practices are lacking in many countries. The general objective of the present study was to determine the quantity and characteristics of fish stocking in metropolitan France. Using a survey-based approach, stocking practices for 2013 by recreational angling clubs in France were quantified, which represented the bulk of fish stocking undertaken in that year. Stocking was found to be practiced by 88.6% of angling clubs in France, representing, on average, 65% of their annual budget. Overall, 22 species were stocked, including 13 native and nine non-native species, with strong variations among species in terms of life stages and body sizes used for stocking. Using Bayesian modelling, a total biomass of 2.029 t, representing approximately 90 million fishes, was estimated to be stocked in France in 2013. In terms of biomass, the most widely stocked species were rainbow trout Oncorhynchus mykiss (Walbaum), brown trout Salmo trutta L., roach Rutilus rutilus (L.), common carp Cyprinus carpio L. and northern pike Esox lucius L. A stocking volume of approximately 60 fishes or 1.5 kg of fish biomass per angler per year seems commonplace in industrialised countries for which data are available. 相似文献
11.
Cody S Szuwalski Katyana A Vert‐Pre André E Punt Trevor A Branch Ray Hilborn 《Fish and Fisheries》2015,16(4):633-648
Assumptions about the future productivity of a stock are necessary to calculate sustainable catches in fisheries management. Fisheries scientists often assume the number of young fish entering a population (recruitment) is related to the biomass of spawning adults and that recruitment dynamics do not change over time. Thus, managers often use a target biomass based on spawning biomass as the basis for calculating sustainable catches. However, we show recruitment and spawning biomass are not positively related over the observed range of stock sizes for 61% of 224 stocks in the RAM Legacy Stock Assessment Database. Furthermore, 85% of stocks for which spawning biomass may not drive recruitment dynamics over the observed ranges exhibit shifts in average recruitment, which is often used in proxies for target biomasses. Our results suggest that the environment more strongly influences recruitment than spawning biomass over the observed stock sizes for many stocks. Management often endeavours to maintain stock sizes within the observed ranges, so methods for setting management targets that include changes within an ecosystem may better define the status of some stocks, particularly as climate changes. 相似文献
12.
13.
Cindy Chu 《Fish and Fisheries》2009,10(2):217-230
Individual transferable quota (ITQ) programmes have been incorporated into many marine fisheries management strategies for 30 years, but their implementation and utility remains controversial. This study provides an overview of the global status of ITQ programmes, the reasons they have been adopted and the changes in stock biomass after their implementation. Eighteen countries currently use ITQs to manage several hundred stocks of at least 249 species. ITQs were adopted in these countries for many reasons: overcapitalization, economic gains, safety concerns for fishers and political change. The implementation of ITQs does not translate into consistent changes in stock biomass. Improvements in 12 of 20 stocks after ITQs were introduced suggest that ITQs can be an effective component of fisheries management strategies, but eight of the stocks continued to decline after ITQs were introduced. This suggests that alternative or complementary measures are needed to sustain those fisheries, such as combining ITQs with more effective total allowable catches, better enforcement and monitoring, and implementing aspects of ecosystem-based fisheries management. 相似文献
14.
Ruben H. Roa-Ureta;Patrícia Amorim;Susana Segurado; 《Fish and Fisheries》2024,25(5):823-836
Most fisheries are conducted without any scientific knowledge about the size and productivity of the stocks that support them. This navigation in the dark in most fisheries is a major obstacle in making them sustainable sources of nutrition for people in general and income for fishers and other economic actors along supply chains. Fisheries that have not been assessed generally are data-intermediate and data-poor, the latter usually having annual time series of landings as the single piece of data available. A major effort in the last two decades has been directed toward developing ‘catch-only’ stock assessment methods, although some of these methods have been tested and found deficient. Here we provide a novel approach to using annual landing time series as the single source of data to qualitatively judge the condition of un-assessed stocks using frequentist cumulative probability ogives, both in terms of stock biomass and fishing mortality. A meta-analysis of the FishSource database allowed us to infer statistical patterns from hundreds of assessed fisheries and thousands of annual landings, biomass, and fishing mortality observations. Four stock-management types were considered separately in the analysis: short-lived and others (mid- to long-lived) stocks, controlled or not controlled by catch limits. Obtained cumulative probability ogives provide clear evaluations of stock biomass and fishing mortality trends in all four stock-management types, leading to actionable information on probable current status and future trends. Using these probability ogives, we developed decision trees that lead to qualitative scores on the exploitation status of un-assessed stocks. 相似文献
15.
Nathaniel Willse;Claire Ober;Hsiao-Yun Chang;Harlisa Harlisa;Tri Ernawati;Duranta D. Kembaren;Cody Szuwalski;Michael J. Wilberg;Yong Chen;Kristin M. Kleisner; 《Fisheries Management and Ecology》2024,31(4):e12691
Management of crustacean fisheries is often data-limited, and techniques used in finfish fisheries are often inappropriate for crustaceans due to life-history differences. Limitations in modeling capacity and data availability make it difficult to determine the status of crustacean stocks using model-based biological reference points (BRPs), but BRPs are a key component of successful fisheries management. Using crustacean fishery case studies depicting model-based and empirical management strategies, we synthesized the current state of crustacean fisheries management with respect to data availability and use of management controls. Input and output controls can be successful with supplemental BRPs, but whatever methods are used must explicitly consider species' unique life-history characteristics. In data-limited fisheries, output controls can effectively conserve a species under high levels of exploitation. Implementation of discrete BRPs can improve sustainability of both emerging and data-rich crustacean fisheries, to make these quantitative metrics a valuable tool for crustacean management globally. 相似文献
16.
Detailed stock assessments, including the estimation of the absolute biomass of the ‘stocks’ exploited by fisheries, are often viewed as the gold standard for indicators of their status. However, such stock assessments are not available for the overwhelming majority of exploited stocks and fisheries globally. This requires the development, testing and dissemination of other, less data‐demanding indicators for use throughout the world, for example, for comparing the status of fisheries between different maritime countries or large marine ecosystems. Stock status plots, initially developed by staff of the United Nations Food and Agriculture Organization to assess global fisheries, are reviewed here, and their most recent incarnation, which accounts for stock rebuilding, is found to provide a robust overview of fisheries and of the major trends besetting them. 相似文献
17.
Drifting fish aggregating devices (dFADs) are extensively used in modern tuna purse seine fisheries. The use of dFADs has greatly improved fishing efficiency and generated substantial economic returns in purse seine fisheries, but adverse impacts on tuna juveniles, associated species and marine ecosystems are still of concern. Based on an analysis of current challenges in dFAD management measures in tuna regional fishery management organisations (t-RFMOs), we explored opportunities to strengthen dFAD management in tuna fisheries. An integrated dFAD management scheme with multiple tools that account for different usage stages of a dFAD needs to be organised to regulate, track, monitor and recover in tuna purse seine fisheries. We recommend that (1) dFAD-associated definitions should be standardised to provide operational guidance for dFAD activities; (2) all deployed dFADs should be counted towards dFAD limits on active dFADs, except those reported as lost and abandoned; (3) a regional dFAD tracking and monitoring program should track dFAD paths based on daily position reported to RFMOs directly, in addition to mandatory dFAD marking requirements; and (4) a framework of compensation mechanisms should provide financial support for joint dFAD recovery and eco-compensation. 相似文献
18.
Yimin Ye Kevern Cochrane Gabriella Bianchi Rolf Willmann Jacek Majkowski Merete Tandstad Fabio Carocci 《Fish and Fisheries》2013,14(2):174-185
Many of the world’s fish stocks are depleted as a result of overexploitation, pollution and habitat loss. The 2002 World Summit on Sustainable Development (WSSD) sets a target for fisheries to maintain or restore stocks to levels that can produce the maximum sustainable yield (MSY) by 2015. We assessed the global stock status and found that 68% were at or above the MSY level in 2008 and that the 2015 target is unlikely to be met. We compiled data for eight indicators to evaluate the sustainability of fisheries and the gap to meet the WSSD target. These indicators show that the overall condition of global fisheries is declining, long‐term benefits are being compromised, and pressures on fisheries are increasing despite fisheries policy and management actions being taken by coastal States. We develop a bio‐economic model to estimate the costs and benefits of restoring overfished stocks. Our results show that the global fishing capacity needs to be cut by 36–43% from the 2008 level, resulting in the loss of employment of 12–15 million fishers and costing US$96–358 billion for buybacks. On the other hand, meeting the WSSD goal will increase annual fishery production by 16.5 million tonnes, annual rent by US$32 billion and improve biodiversity and functioning of marine ecosystems. However, progress towards rebuilding has been hindered by an unwillingness or inability to accept the short‐term socio‐economic consequences associated with rebuilding fisheries. Thus, there is a pressing need for integration of rebuilding plans into national political and economic decision‐making. 相似文献
19.
Total allowable catch restrictions (hereafter referred to as catch quotas) play an important role in maintaining healthy fish stocks. While studies have identified a positive relationship between catch quota implementation and improved stock status, these methods are subject to selection bias as catch quotas are typically applied to stocks that are depleted. We address this challenge using the synthetic control method, which estimates the causal effect of catch quotas on fishing mortality and biomass by predicting a synthetic counterfactual outcome. We focus on high seas stocks (tunas, billfishes, and sharks) managed by tuna Regional Fisheries Management Organizations (tRFMOs), first providing an overview of stock status and current management measures in place. We find that implementation of catch quotas by tRFMOs has more than doubled over the past decade. Second, we predict the hypothetical fishing mortality and biomass trajectory for seven high seas quota-managed stocks in absence of a catch quota. These “synthetic non-quota stocks” are predicted using a weighted selection of high seas non-quota stocks. Credibility of the synthetic non-quota stocks is evaluated through diagnostic checks, and robustness tests assess sensitivity to study design. Five credible fishing mortality synthetic controls are predicted: three add support to the hypothesis that catch quotas successfully reduce fishing mortality, while two find that catch quotas increase fishing mortality. While our analysis is limited in scope, given that all seven quota-managed stocks are managed under a single tRFMO, we highlight the potential for the synthetic control method in fisheries management evaluation. 相似文献
20.
The establishment of no‐take marine reserves has been increasingly promoted as a key measure to achieve conservation and sustainability goals in fisheries. Regardless of the wide range of benefits cited, the effectiveness of reserve establishment depends critically on fisheries management outside the reserves. We construct a bioeconomic model of a fishery that allows for the establishment of a no‐take marine reserve and evaluate how the choice of the off‐reserve management target influences the effectiveness of reserve establishment. We evaluate two biomass targets: (i) BMSY or the biomass that produces the maximum sustainable yield (MSY) and (ii) BMEY or the biomass that maximizes the net present value of the returns to fishing. The parameterized model shows that, for a wide range of scenarios, the fishery will be better off in terms of both conservation and economic objectives when the no‐take reserve is established in conjunction with the BMEY target rather than with the BMSY target. Model results further show that the opportunity cost of securing additional fish biomass, in both deterministic and stochastic environments, is lower when the reserve size is increased under the BMEY target. This finding is important because marine reserves have been established as a key measure to restore depleted fish stocks, and the results suggest that this objective can be achieved with lower economic costs in a BMEY managed fishery. 相似文献