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1.
Despite the growing popularity of ecosystem‐based management (EBM) in national legislation and in research and institutional literature, there is often an implementation gap ‘on the ground’, impeding widespread adoption in fisheries. This gap reflects in part the differing understandings of EBM held by fishermen and by management institutions. To explore and seek to close this gap, the underlying principles of EBM considered priorities by fishermen were systematically compared with the priorities identified in the published literature. The fishermen's priorities were determined by asking Atlantic Canadian fishermen to identify the EBM principles they consider most important. Four priority principles were identified: Sustainability, Stakeholder Involvement, Develop Long‐Term Objectives and Use of All Forms of Knowledge. The latter two were not frequently noted as priorities in the literature, while some literature priorities were less commonly chosen by fishermen, indicating a significant difference in perspectives on EBM. The rationale for fishermen's choice of priorities was explored by analysing the fishery management issues they raised – many directly connected to the above four priorities. In addition, another principle, Commit to Principles of Equity, often arose as an implicit priority among fishermen. We suggest that success in implementation of EBM may depend on reconciling differing priorities among its underlying principles, and combining knowledge and expertise from fishermen with research and institutional sources. The comparative methodology used here, which could be replicated elsewhere, should lead to better recognition of local challenges in EBM implementation and encourage support for EBM, to further its contribution to sustainable fisheries.  相似文献   

2.
International instruments of fisheries governance have set the core principles for the management of highly migratory fishes. We evaluated the progress of tuna Regional Fisheries Management Organizations (tRFMOs) in implementing the ecological component of ecosystem‐based fisheries management (EBFM). We first developed a best case tRFMO for EBFM implementation. Second, we developed criteria to evaluate progress in applying EBFM against this best case tRFMO. We assessed progress of the following four ecological components: target species, bycatch species, ecosystem properties and trophic relationships, and habitats. We found that many of the elements necessary for an operational EBFM are already present, yet they have been implemented in an ad hoc way, without a long‐term vision and a formalized plan. Overall, tRFMOs have made considerable progress monitoring the impacts of fisheries on target species, moderate progress for bycatch species, and little progress for ecosystem properties and trophic relationships and habitats. The tRFMOs appear to be halfway towards implementing the ecological component of EBFM, yet it is clear that the “low‐hanging fruit” has been plucked and the more difficult, but surmountable, issues remain, notably the sustainable management of bycatch. All tRFMOs share the same challenge of developing a formal mechanism to better integrate ecosystem science and advice into management decisions. We hope to further discussion across the tRFMOs to inform the development of operational EBFM plans.  相似文献   

3.
Recent articles in high‐profile journals advocating the widespread establishment of economic rights‐based approaches for managing fisheries has re‐kindled the debate over the efficacy of incentive‐based vs. regulatory‐based management approaches. Inspection of these works, written from the particular perspectives of economics, fisheries biology, or marine ecology, reveals that advocates of rights‐based regimes such as Individual Transferrable Quotas are sometimes recommending these policy instruments for quite different reasons. Hence, the advantageous attributes of rights‐based approaches from the perspective of one discipline may be quite different when seen from the perspective of another discipline. This is of concern as it exposes a tendency for particular disciplines to consider only the advantages of rights‐based approaches, such as establishing a harvest cap, but to implicitly discount the disadvantages such as less attention being paid to critical ecological and ecosystem issues.  相似文献   

4.
Reconciling food security, economic development and biodiversity conservation is a key challenge, especially in the face of the demographic transition characterizing many countries in the world. Fisheries and marine ecosystems constitute a difficult application of this bio‐economic challenge. Many experts and scientists advocate an ecosystem approach to manage marine socio‐ecosystems for their sustainability and resilience. However, the ways by which to operationalize ecosystem‐based fisheries management (EBFM) remain poorly specified. We propose a specific methodological framework—viability modelling—to do so. We show how viability modelling can be applied using four contrasted case‐studies: two small‐scale fisheries in South America and Pacific and two larger‐scale fisheries in Europe and Australia. The four fisheries are analysed using the same modelling framework, structured around a set of common methods, indicators and scenarios. The calibrated models are dynamic, multispecies and multifleet and account for various sources of uncertainty. A multicriteria evaluation is used to assess the scenarios’ outcomes over a long time horizon with different constraints based on ecological, social and economic reference points. Results show to what extent the bio‐economic and ecosystem risks associated with the adoption of status quo strategies are relatively high and challenge the implementation of EBFM. In contrast, strategies called ecoviability or co‐viability strategies, that aim at satisfying the viability constraints, reduce significantly these ecological and economic risks and promote EBFM. The gains associated with those ecoviability strategies, however, decrease with the intensity of regulations imposed on these fisheries.  相似文献   

5.
While there has been a growing concern for the adverse ecological impacts of fishing, progress on incorporating these into operational fisheries management has been slow. Many fisheries management organizations have addressed the problem of overharvesting and over‐capitalization first. In this domain, the question of access regulation has gained growing recognition as a key dimension of fisheries sustainability, leading to recommendation and progressive implementation of rights‐based systems, in particular Individual Transferrable Quotas (ITQs). While adjustments in fishing capacity resulting from the implementation of these systems may entail a reduction in some unwanted ecosystem impacts of fishing, it is also recognized that they will not be sufficient to achieve the ecological outcomes increasingly demanded by the global community. There is thus a need to examine the possibilities for a common management framework for dealing with both over‐capitalization of fisheries and adverse ecological effects of fishing. In this paper, we examine the feasibility of incorporating greater ecosystem goods and services into ITQ policy instruments initially designed with a narrow focus on commercial target species. We consider the advantages and limitations of alternative approaches in this respect and identify some of the practical issues associated with the different alternatives, in particular the underpinning knowledge requirements. We argue that given the need for increasingly streamlined management processes, further investigation into practical ways forward in this domain is crucial if management of fisheries is to achieve economic efficiency while fully encompassing the ecologically sustainable development objectives of ecosystem‐based fisheries management.  相似文献   

6.
The increasing need to account for the many factors that influence fish population dynamics, particularly those external to the population, has led to repeated calls for an ecosystem approach to fisheries management (EAFM). Yet systematically and clearly addressing these factors, and hence implementing EAFM, has suffered from a lack of clear operational guidance. Here, we propose 13 main factors (shift in location, migration route or timing, overfishing (three types), decrease in physiology, increase in predation, increase in competition, decrease in prey availability, increase in disease or parasites and a decline in habitat quality or habitat quantity) that can negatively influence fish populations via mechanisms readily observable in ~20 population features. Using these features as part of a diagnostic framework, we develop flow charts that link probable mechanism(s) underlying population change to the most judicious management actions. We then apply the framework for example case studies that have well‐known and documented population dynamics. To our knowledge, this is the first attempt to provide a clearly defined matrix of all the probable responses to the most common factors influencing fish populations, and to examine possible diagnostics simultaneously, comparatively and relatively in an attempt to elucidate the most probable mechanisms responsible. The framework we propose aims to operationalize EAFM, thereby not only better diagnosing factors influencing fish populations, but also suggesting the most appropriate management interventions, and ultimately leading to improved fisheries. We assert the framework proposed should result in both better use of limited analytical and observational resources and more tailored and effective management actions.  相似文献   

7.
A performance assessment was conducted of regional fisheries management organizations’ (RFMOs’) bycatch governance, one element of an ecosystem approach to fisheries management. Obtaining a mean score of 25%, with a 64% CV, collectively the RFMOs have large governance deficits. Individually, there has been mixed progress, with some RFMOs having made substantial progress for some governance elements. There has been nominal progress in gradually transitioning to ecosystem‐based fisheries management: controls largely do not account for broad or multispecies effects of fishing, and cross‐sectoral marine spatial planning is limited. Regional observers collect half of minimum information needed to assess the efficacy of bycatch measures. Over two‐thirds of RFMO‐managed fisheries lack regional observer coverage. International exchange of observers occurs in one‐third of programmes. There is no open access to research‐grade regional observer data. Ecological risk assessments focus on effects of bycatch removals on vulnerable species groups and effects of fishing on vulnerable benthic marine ecosystems. RFMOs largely do not assess or manage cryptic, generally undetectable sources of fishing mortality. Binding measures address about one‐third of bycatch problems. Eighty per cent of measures lack explicit performance standards against which to assess efficacy. Measures are piecemeal, developed without considering potential conflicts across vulnerable groups. RFMOs employ 60% of surveillance methods required to assess compliance. A lack of transparency and limited reporting of inspection effort, identified infractions, enforcement actions and outcomes further limits the ability to assess compliance. Augmented harmonization could help to fill identified deficits.  相似文献   

8.
Ecosystem‐based fishery management requires considering the effects of actions on social, natural and economic systems. These considerations are important for forage fish fisheries, because these species provide ecosystem services as a key prey in food webs and support valuable commercial fisheries. Forage fish stocks fluctuate naturally, and fishing may make these fluctuations more pronounced, yet harvest strategies intended to ameliorate these effects might adversely affect fisheries and communities. Here, we evaluate trade‐offs among a diverse suite of management objectives by simulating outcomes from several harvest strategies on forage fish species. We demonstrate that some trade‐offs (like those between catches and minimizing collapse length) were universal among forage species and could not be eliminated by the use of different control rules. We also demonstrate that trade‐offs vary among forage fish species, with strong trade‐offs between stable, high catches and high‐biomass periods (“bonanzas”) for menhaden‐ and anchovy‐like fish, and counterintuitive trade‐offs for sardine‐like fish between shorter collapses and longer bonanzas. We find that harvest strategies designed to maintain stability in catches will result in more severe collapses. Finally, we show that the ability of assessments to detect rapid changes in population status greatly affects control rule performance and the degree and type of trade‐offs, increasing the risk and severity of collapses and reducing catches. Together, these results demonstrate that while default harvest strategies are useful in data‐poor situations, management strategy evaluations that are tailored to specific forage fish may better balance trade‐offs.  相似文献   

9.
The advent of an ecosystem‐based approach dramatically expanded the scope of fisheries management, creating a critical need for new kinds of data and quantitative approaches that could be integrated into the management system. Ecosystem models are needed to codify the relationships among drivers, pressures and resulting states, and to quantify the trade‐offs between conflicting objectives. Incorporating ecosystem considerations requires moving from the single‐species models used in stock assessments, to more complex models that include species interactions, environmental drivers and human consequences. With this increasing model complexity, model fit can improve, but parameter uncertainty increases. At intermediate levels of complexity, there is a ‘sweet spot’ at which the uncertainty in policy indicators is at a minimum. Finding the sweet spot in models requires compromises: for example, to include additional component species, the models of each species have in some cases been simplified from age‐structured to logistic or bioenergetic models. In this paper, we illuminate the characteristics, capabilities and short‐comings of the various modelling approaches being proposed for ecosystem‐based fisheries management. We identify key ecosystem needs in fisheries management and indicate which types of models can meet these needs. Ecosystem models have been playing strategic roles by providing an ecosystem context for single‐species management decisions. However, conventional stock assessments are being increasingly challenged by changing natural mortality rates and environmentally driven changes in productivity that are observed in many fish stocks. Thus, there is a need for more tactical ecosystem models that can respond dynamically to changing ecological and environmental conditions.  相似文献   

10.
Gulf (Brevoortia patronus, Clupeidae) and Atlantic menhaden (Brevoortia tyrannus, Clupeidae) support large fisheries that have shown substantial variability over several decades, in part, due to dependence on annual recruitment. Nevertheless, traditional stock–recruitment relationships lack predictive power for these stocks. Current management of Atlantic menhaden explicitly treats recruitment as a random process. However, traditional methods for understanding recruitment variability carry the very specific hypothesis that the effect of adult biomass on subsequent recruitment occurs independently of other ecosystem factors such as food availability and predation. Here, we evaluate the predictability of menhaden recruitment using a model‐free approach that is not restricted by these strong assumptions. We find that menhaden recruitment is predictable, but only when allowing for interdependence of stock with other ecological factors. Moreover, while the analysis confirms the presence of environmental effects, the environment alone does not readily account for the complexity of menhaden recruitment dynamics. The findings set the stage for revisiting recruitment prediction in management and serve as an instructive example in the ongoing debate about how to best treat and understand recruitment variability across species and fisheries.  相似文献   

11.
In the Abrolhos Bank (Southwest Atlantic), multidimensional indicators were used in sustainability assessments of data‐poor reef fisheries. Potential impacts, risks and stocks vulnerabilities were evaluated based on biological, environmental, social and economic aspects by combining both adapted productivity and susceptibility analysis (PSA) and scale intensity consequence analysis (SICA). Data were obtained from local surveys with stakeholders and experts and from literature. A value chain map revealed final consumers at many locations and middleman presence. Vulnerability to overexploitation ranged from low (Cephalopholis fulva (L.), Lutjanus synagris (L.) and Ocyurus chrysurus (Bloch)) to moderate (Lutjanus jocu (Bloch & Schneider), Epinephelus morio (Val.) and Mycteroperca bonaci Poey). While moderate consequences of the catches were observed to C. fulva, major consequences were identified to the other five stocks. The main threat to coral reef habitats was found to be mining wastes. Poor governance may constrain fisheries sustainability in the region, while the empowerment of fishers in both governance and post‐harvest processes should enhance it.  相似文献   

12.
We present a framework for results‐based management (RBM) of commercial fisheries. The core idea of RBM is to reduce micromanagement by delegating management responsibility to resource users. The RBM framework represents an industrial organization approach to co‐management and comprises three defining processes, conducted by three independent “agents”: (i) an “authority” defines specific and measurable and achievable objectives (outcome targets, OTs) for the utilization of fisheries resources, (ii) resource user organizations (termed “operators”) take responsibility for achieving these OTs and provide documentation that (iii) allows independent “auditors” to evaluate the achievement of OTs. Using incentive mechanisms, notably deregulation, RBM grants operators the flexibility to develop and implement innovative and cost‐effective ways to achieve OTs. The feasibility of implementing RBM in five European fisheries was investigated in cooperation with relevant stakeholders through artificial planning processes and computer simulations. The operators involved were enthusiastic, and new management plans were drafted based on the framework. These included socioeconomic OTs in addition to traditional stock objectives, encompassing an ecosystem approach. Several issues are in need of further research to consolidate the approach and prepare the ground for practical implementation, including: the specification of the legal and regulatory framework required to underpin RBM, details of transitional arrangements when shifting towards RBM (including cost‐sharing) and the development of necessary organizational capacity for operators. Initially, we therefore envisage the framework being applied to high‐value single‐species fisheries, with a limited number of participants, which are adequately represented by a competent organization.  相似文献   

13.
Models of human dimensions of fisheries are important to understanding and predicting how fishing industries respond to changes in marine ecosystems and management institutions. Advances in computation have made it possible to construct agent‐based models (ABMs)—which explicitly describe the behaviour of individual people, firms or vessels in order to understand and predict their aggregate behaviours. ABMs are widely used for both academic and applied purposes in many settings including finance, urban planning and the military, but are not yet mainstream in fisheries science and management, despite a growing literature. ABMs are well suited to understanding emergent consequences of fisher interactions, heterogeneity and bounded rationality, especially in complex ecological, social and institutional contexts. For these reasons, we argue that ABMs of human behaviour can contribute significantly to human dimensions of fisheries in three areas: (a) understanding interactions between multiple management institutions; (b) incorporating cognitive and behavioural sciences into fisheries science and practice; and (c) understanding and projecting the social consequences of management institutions. We provide simple examples illustrating the potential for ABMs in each of these areas, using conceptual (“toy”) versions of the POSEIDON model. We argue that salient strategic advances in these areas could pave the way for increased tactical use of ABMs in fishery management settings. We review common ABM development and application challenges, with the aim of providing guidance to beginning ABM developers and users studying human dimensions of fisheries.  相似文献   

14.
Managing fisheries resources to maintain healthy ecosystems is one of the main goals of the ecosystem approach to fisheries (EAF). While a number of international treaties call for the implementation of EAF, there are still gaps in the underlying methodology. One aspect that has received substantial scientific attention recently is fisheries‐induced evolution (FIE). Increasing evidence indicates that intensive fishing has the potential to exert strong directional selection on life‐history traits, behaviour, physiology, and morphology of exploited fish. Of particular concern is that reversing evolutionary responses to fishing can be much more difficult than reversing demographic or phenotypically plastic responses. Furthermore, like climate change, multiple agents cause FIE, with effects accumulating over time. Consequently, FIE may alter the utility derived from fish stocks, which in turn can modify the monetary value living aquatic resources provide to society. Quantifying and predicting the evolutionary effects of fishing is therefore important for both ecological and economic reasons. An important reason this is not happening is the lack of an appropriate assessment framework. We therefore describe the evolutionary impact assessment (EvoIA) as a structured approach for assessing the evolutionary consequences of fishing and evaluating the predicted evolutionary outcomes of alternative management options. EvoIA can contribute to EAF by clarifying how evolution may alter stock properties and ecological relations, support the precautionary approach to fisheries management by addressing a previously overlooked source of uncertainty and risk, and thus contribute to sustainable fisheries.  相似文献   

15.
The social and economic importance of small‐scale fisheries is frequently under‐valued, and they are rarely effectively managed. There is now growing consensus on how these fisheries could be managed for sustainability and to minimize the risks of crossing undesirable thresholds. Using a concept developed in health care, these approaches have been referred to as primary fisheries management. By encouraging the use of best‐available information in a precautionary way, the approaches will facilitate sustainable use and should therefore be encouraged, but they accept high scientific and implementation uncertainties as unavoidable because of limited management and enforcement resources and capacity. It is important to recognize that this limitation will result in social costs, because application of a precautionary approach in the face of high uncertainties will require forgoing potential sustainable benefits. Acceptance of primary fisheries management as a final and sufficient goal could therefore add a further constraint on the possibility of fishing communities escaping the poverty trap. Primary fisheries management should be seen as a first and minimum target for fisheries where there is currently no or inadequate management, but the longer‐term goal should still be well informed and adaptive management that strives for optimal benefits, referred to here as tertiary management.  相似文献   

16.
We have developed a set of tools that operate within an aquatic geographic information system to improve the accessibility, and usability of remote‐sensed satellite and computer‐modeled oceanographic data for marine science and ecosystem‐based management. The tools form the Pelagic Habitat Analysis Module (PHAM), which can be applied as a modeling platform, an investigative aid in scientific research, or utilized as a decision support system for marine ecological management. Applications include fisheries, marine biology, physical and biological oceanography, and marine spatial management. The GIS provides a home for diverse data types and automated tools for downloading remote sensed and global circulation model data. Within the GIS environment, PHAM provides a framework for seamless interactive four‐dimensional visualization, for matching between disparate data types, for flexible statistic or mechanistic model development, and for dynamic application of user developed models for habitat, density, and probability predictions. Here we describe PHAM in the context of ecosystem‐based fisheries management, and present results from case study projects which guided development. In the first, an analysis of the purse seine fishery for tropical tuna in the eastern Pacific Ocean revealed oceanographic drivers of the catch distribution and the influence of climate‐driven circulation patterns on the location of fishing grounds. To support management of the Common Thresher Shark (Alopias vulpinus) in the California Current Ecosystem, a simple empirical habitat utilization model was developed and used to dynamically predict the seasonal range expansion of common thresher shark based on oceanographic conditions.  相似文献   

17.
Sharks and their cartilaginous relatives are one of the world's most threatened species groups. The primary cause is overfishing in targeted and bycatch fisheries. Reductions in fishing mortality are needed to halt shark population declines. However, this requires complex fisheries management decisions, which often entail trade‐offs between conservation objectives and fisheries objectives. We propose the mitigation hierarchy (MH)—a step‐wise precautionary approach for minimizing the impacts of human activity on biodiversity—as a novel framework for supporting these management decisions. We outline a holistic conceptual model for risks to sharks in fisheries, which includes biophysical, operational and socioeconomic considerations. We then demonstrate how this model, in conjunction with the MH, can support risk‐based least cost shark conservation. Through providing examples from real‐world fishery management problems, we illustrate how the MH can be applied to a range of species, fisheries and contexts, and explore some of the opportunities and challenges hereto. Finally, we outline next steps for research and implementation. This is important in the context of increasing international regulation of shark fishing and trade, which must lead to reductions in shark mortality, while managing trade‐offs between conservation objectives and the socioeconomic value of fisheries.  相似文献   

18.
Worldwide, most sea cucumber fisheries are ineffectively managed, leading to declining stocks and potentially eroding the resilience of fisheries. We analyse trends in catches, fishery status, fishing participation and regulatory measures among 77 sea cucumber fisheries through data from recent fishery reports and fishery managers. Critical gaps in fisheries biology knowledge of even commonly targeted species undermine the expected success of management strategies. Most tropical fisheries are small‐scale, older and typified by numerous (>8) species, whereas temperate fisheries are often emerging, mono‐specific and industrialized. Fisher participation data indicated about 3 million sea cucumber fishers worldwide. Fisher participation rates were significantly related to the average annual yield. permanova analysis showed that over‐exploited and depleted fisheries employed different sets of measures than fisheries with healthier stocks, and a non‐metric multidimensional scaling ordination illustrated that a broad set of regulatory measures typified sustainable fisheries. SIMPER and regression tree analyses identified that the dissimilarity was most related to enforcement capacity, number of species harvested, fleet (vessel) controls, limited entry controls and rotational closures. The national Human Development Index was significantly lower in countries with over‐exploited and depleted fisheries. Where possible, managers should limit the number of fishers and vessel size and establish short lists of permissible commercial species in multispecies fisheries. Our findings emphasize an imperative to support the enforcement capacity in low‐income countries, in which risk of biodiversity loss is exceptionally high. Solutions for greater resilience of sea cucumber stocks must be embedded within those for poverty reduction and alternative livelihood options.  相似文献   

19.
Ecosystem‐based management of fisheries aims to allow sustainable use of fished stocks while keeping impacts upon ecosystems within safe ecological limits. Both the FAO Code of Conduct for Responsible Fisheries and the Aichi Biodiversity Targets promote these aims. We evaluate implementation of ecosystem‐based management in six case‐study fisheries in which potential indirect impacts upon bird or mammal predators of fished stocks are well publicized and well studied. In particular, we consider the components needed to enable management strategies to respond to information from predator monitoring. Although such information is available in all case‐studies, only one has a reference point defining safe ecological limits for predators and none has a method to adjust fishing activities in response to estimates of the state of the predator population. Reference points for predators have been developed outside the fisheries management context, but adoption by fisheries managers is hindered a lack of clarity about management objectives and uncertainty about how fishing affects predator dynamics. This also hinders the development of adjustment methods because these generally require information on the state of ecosystem variables relative to reference points. Nonetheless, most of the case‐studies include precautionary measures to limit impacts on predators. These measures are not used tactically and therefore risk excessive restrictions on sustainable use. Adoption of predator reference points to inform tactical adjustment of precautionary measures would be an appropriate next step towards ecosystem‐based management.  相似文献   

20.
Scientists feel discomfort when they are asked to create certainty, where none exists, for use as an alibi in policy‐making. Recently, the scientific literature has drawn attention to some pitfalls of simulation‐based fisheries management‐strategy evaluation (MSE). For example, while estimates concerning central tendencies of distributions of simulation outcomes are usually fairly robust because they are conditioned on ample data, estimates concerning the tails of distributions (such as the probability of falling below a critical biomass) are usually conditional on few data and thus often rely on assumptions that have no strong knowledge base. The clients of scientific advice, such as the European Commission, are embracing the mechanization of the evaluation of proposed Harvest Control Rules against the precautionary principle and management objectives. Where the fisheries management institutions aim for simple answers from the scientists, giving ‘green/red light’ to a proposed management strategy, the scientists are forced into a split position between satisfying the demands of their advisory role and living up to the standards of scientific rigour. We argue against the mechanization of scientific advice that aims to incorporate all relevant processes into one big model algorithm that, after construction, can be run without circumspection. We rather encourage that fisheries advice should be a dynamic process of expert judgement, incorporating separate parallel concurrent, lines of scientific evidence, from quantitative and qualitative modelling exercises and factual knowledge of the biology and the fishery dynamics. This process can be formalized to a certain degree and can easily accommodate stakeholder viewpoints.  相似文献   

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