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1.
Bernerd Fulanda Jun OhtomiElizabeth Mueni Edward Kimani 《Ocean & Coastal Management》2011,54(5):401-414
The present study assessed trends in resource-use, partitioning and management in the Ungwana Bay fishery, Kenya, using surplus production models. The fishery is one of East Africa’s important marine fisheries sustaining a bottom trawl commercial fishery and a resident-migrant artisanal fishery. Two models: Schaefer (1954) and Gulland and Fox (1975) were applied to catch-effort data over a 21-year period to model maximum sustainable yield (MSY) and optimal effort (fMSY) to examine the status of resource exploitation and provide reference points for sustainable management. In the artisanal fishery, model MSYs range from 392-446 t to 1283-1473 t for shrimps and fish respectively compared to mean annual landings of 60 t for shrimp and 758 t for fish. These landings represent <50% of the model MSYs suggesting under exploitation in the sub-sector. Moreover, current fishing effort applied stands at <0.5 fMSY. On the other hand, mean annual landings in bottom trawl commercial fishery, at about 330 t for shrimps and 583 t and fish represent about 90% of the model MSYs of 352-391 t and 499-602 t for shrimps and fish respectively. Therefore, the bottom trawl commercial fishery is likely under full exploitation. Similarly, the current effort is estimated at >0.7 fMSY. Resource management in the bay is faced with numerous problems including resource-use conflicts, poor economic conditions in artisanal fishery, poor legislation, and inadequate research augmented by poor reporting systems for catch-effort statistics. Thus, the fishery lacks clearly defined exploitation regimes. Fisheries research and assessment of the marine resources are important for sustainability of the fishery. Moreover, income diversification in the poverty ridden artisanal fishery would go a long way in addressing resource-use conflicts and use of deleterious fishing methods in the sub-sector. Borrowing from the successes of the Japanese community-based fisheries resource management (CBFRM) which has easily resolved numerous fisheries management issues in coastal small-scale commercial fisheries, and the beach management unit (BMU) system which has been applied to the artisanal fisheries of south coast Kenya with enormous benefits, it is envisaged that a hybrid CBFRM-BMU system presents the best approach to sustainable resource-use in the Ungwana Bay fishery. 相似文献
2.
《Marine Policy》2015
Effective management of artisanal fisheries requires understanding fishers, their behaviors, and the drivers that underpin their choices. Behavioral drivers are critical links in understanding the interactions between social and ecological systems and can help inform effective management approaches. A Bayesian Belief Network modeling approach was used to investigate a diverse range of qualitative and quantitative social and ecological drivers of spatial location choice in a multi-species artisanal dive fishery in Costa Rica. Empirical and observer data used to populate the BBN showed the influence of economic factors, environmental conditions as well as social interactions on the decision-making process of spatial location choice. Good governance scenarios represented by Responsible Fisheries Marine Areas Management were analyzed for both hookah and free diving methods to assess the effects of responsible fishing on the fishers and the fishery. Model based-scenario analysis suggests that management interventions should consider the fisher's potential behavioral responses in the context of environmental variability, dependence on cultural assets, and food security. The results show that there is a need to understand fisher's decisions based on broad socio-ecological system understanding and consider the environmental outcomes alongside food security and the cultural significance of different marine species to fishing communities. 相似文献
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《Marine Policy》2013
A recent opinion piece published in Nature summarises the differing views held by Pauly on the one hand, and by Hilborn and Branch on the other, regarding the challenge faced by fishery scientists in accurately determining the status of the world's fisheries. Both commentaries discuss whether the fisheries catch data published by FAO can by themselves be used to infer fishery status. The purpose of this short communication is to examine both views and to propose additional solutions to contribute to the understanding of fishery status globally. These may include expanding data-poor stock assessment methods as well as community-based data collection and monitoring programs, particularly in developing countries. 相似文献
5.
Sean Pascoe Rodrigo Bustamante Chris Wilcox Mark Gibbs 《Ocean & Coastal Management》2009,52(2):130-138
In many circumstances, quantitative assessment of fisheries management options is either impossible due to data deficiencies or impractical given the size of the fishery. Quantitative analysis of spatial management options in particular is complicated, as information on spatial fleet and stock dynamics is often unavailable and spatial models are difficult to construct. In this paper, a qualitative framework is presented that aids in the analysis of alternative spatial management options in coastal fisheries. The framework combines expert opinion and the Analytic Hierarchy Process (AHP) to determine which options perform best taking into account the multiple objectives inherent in fisheries management. 相似文献
6.
《Marine Policy》2015
Stock enhancement or “assisted recruitment” for fisheries management in Australia is at an experimental R&D phase. Development of the science has focused largely on finfish targeted by the recreational sector; however it is considered that high value invertebrates will be the best candidates for commercial scale fisheries enhancement. Three main ingredients are required; technical capacity, governance capability, and the ‘correct’ species. The technical capacity needed is in the area of hatchery production and wild release methodologies, whilst the governance capability needed is informed policy that accounts for the complexities and interdisciplinary nature of stock enhancement. In particular, the appropriate articulation of policy to support economic development and integration into wild fisheries is currently lacking. If successful stock enhancement is implemented, the nature of fisheries management changes because the recruitment side of the fisheries equation is under substantial control, rather than just the production side. Management responses will require significant innovation, with a renewed emphasis on understanding the stock, rather than policing the fishers. By way of illustration, recent initiatives and key challenges encountered in Australian invertebrate fisheries are investigated through case studies. An example of a commercially-viable enhancement fishery that reflects solutions to the key challenges is also presented. The review ends with an argument to re-establish the context of stock enhancement in the discipline of ecological enhancement. This is a crucial and positive step forward for it recognises that, in principle, any renewable aquatic ecosystem has the potential to be enhanced instead of just depleted. 相似文献
7.
Past fisheries development policies in Malaysia are assessed and new grounds for managing the Malaysian fisheries are explored. Some incompatibility in the goals for fishery development are discerned, especially those of increasing domestic landings through mechanization and resource conservation. Future management efforts should be based on a fuller understanding of the fishery stock and regional management of fish stocks. Aquaculture is often seen as a plausible alternative in order to augment supplies from the capture fisheries. A comprehensive multidisciplinary approach is needed to transform and commercialize traditional, experience-dependent culture systems into technology-packaged systems based on scientific methods. There is also substantial potential for the development of recreational fisheries. 相似文献
8.
当前,对渔业资源评估模型的诊断与选择,主要依赖于模型对观察数据的拟合度,很少评价模型的预测能力、并将其作为评价渔业资源评估与管理质量的依据。为此,本文利用后向预报方法评价了印度洋黄鳍金枪鱼(Thunnus albacores)资源评估模型的预测能力,并在此基础上分析了印度洋黄鳍金枪鱼的资源评估与管理质量。研究表明,在利用贝叶斯剩余产量模型对印度洋黄鳍金枪鱼进行资源评估时,存在如下问题:(1)拟合较好的模型其预测能力较差;(2)利用不同时段数据拟合模型时,采用DIC(Deviance Information Criterion)选择的最佳模型缺少稳定性;(3)不同模型估计的TAC (Total Allowable Catch)存在较大差异。据此可以判断,利用贝叶斯剩余产量模型对印度洋黄鳍金枪鱼进行资源评估与管理效果较差。本研究结果表明:(1)利用后向预报方法可评价模型的预测能力、DIC选择模型的稳定性,从而能在一定程度上判断模型模拟的种群演化动态是否正确、资源评估结果是否存在问题;(2)利用后向预报方法可揭示评估结果的不确定性及其可能引起的渔业管理风险,从而有利于避免渔业管理风险、实现渔业管理目标。 相似文献
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《Marine Policy》2017
Eco-labeling is a market-driven mechanism to promote sustainable fisheries. The most widely used certification scheme for seafood eco-labeling is issued by the Marine Stewardship Council (MSC), but the MSC has been criticized for favoring large-scale industrial fisheries. The benefits from eco-labeling can potentially be significant, ranging from price premiums to enriched understanding of fisheries management among fishers; however, anecdotal evidence from MSC-certified fisheries across various countries highlights the struggle of many small-scale fisheries to meet the costs of certification. The lack of environmental awareness in domestic markets can impede the spread of MSC eco-labeling among small-scale fisheries. In the absence of consumer preferences for seafood sustainability, and without subsidies, the certification may not be an appropriate tool for small-scale seafood producers. Examination of the case of an MSC-certified small-scale fishery suggests some efforts to achieve economies of scale; multi-species fisheries can apply for MSC certification as a single unit of assessment, and fisheries can cooperate with neighboring fisheries that target the same fish stock to share assessment costs. In a market where no price premium has been generated, effective face-to-face marketing is pivotal. The MSC will need to be committed to pursuing price premiums in new markets if it is to extend its reach further to small-scale fisheries. 相似文献
11.
Cynoscion guatucupa Cuvier 1829 is a migratory pelagic fish species, which has a wide geographical distribution. It is the most important fishing resource for local communities in Bahía Blanca estuary and has been captured by artisanal fishermen since the 1900s. The industrial fleet has been fishing this species in the coastal area of Buenos Aires province since the 1950s, and, since 1970, landings have increased sharply. Between 2000 and 2004, the artisanal fishery in the estuarine waters of Bahía Blanca collapsed. Variations in total landings of the artisanal fleet might have arisen from the environmental variables within the estuary, fishing activity in the surrounding sea region, local pressure within the estuary and/or several other variables. Our results suggest that neither oceanographic parameters nor local pressure seem to have influenced the artisanal fishery of C. guatucupa in the estuarine region. Instead, this fishery seems to have been partially influenced by the increasing fishing pressure exerted by the industrial fishing fleet operating in open waters around the estuary. This study emphasizes the need to take into account fisheries data from both the estuarine environment and the surrounding sea region, particularly when designing management plans for the sustainable use of migrating fish resources. 相似文献
12.
《Marine Policy》2015
Some of the most important development goals for the countries and territories of the Western and Central Pacific Ocean (WCPO) involve the sustainable management of their fisheries in light of environmental, economic and social uncertainties. The responses of fish populations to variability in the marine environment have implications for decision making processes associated with resource management. There is still considerable uncertainty in estimating the responses of tuna populations to short-to-medium-term variability and longer-term change in the oceanic environment. A workshop was organised to examine how advances in oceanography, fisheries science and fisheries economics could be applied to the tuna fisheries of the WCPO and in doing so identify research priorities to improve understanding relevant to progressing management. Research priorities identified included: (i) improved parameterisation of end to end ecosystem model components, processes and feedbacks through expanded biological observations and incorporation of higher resolution climate models; (ii) development of seasonal and inter-annual forecasting tools enabling management responses to short-term variability in tuna distributions and abundances; (iii) improved understanding of the population dynamics of and the energy transfer efficiencies between food web components; (iv) assessment of the optimal value of access rights and overall fishery value under multiple scenarios of tuna distribution and abundance and influences on decision making by fisheries managers and fleets and (v) development of management strategy evaluation frameworks for utilisation in the implementing and testing of fishery management procedures and to help prioritise research directions and investment. Issues discussed and research priorities identified during the workshop have synergies with other internationally managed fisheries and therefore are applicable to many other fisheries. 相似文献
13.
《Marine Policy》2016
In the Northeast Atlantic, elasmobranchs are a common bycatch in many fisheries, including demersal trawls, longlines, or gillnets and many countries do not have regulations or any control over the amount taken. In the Mid Atlantic, the Azores EEZ (Exclusive Economic Zone), small-scale fishing operations, artisanal and hook-and-line fishing methods are responsible for part of local total landed elasmobranch biomass, although some species are specifically focused and severely harvested by international large-scale fleets. This work provides a review and analysis of the commercial elasmobranch fisheries in the Azores EEZ, and its evolution over the last two decades, highlighting management priorities, taking into account the Northeast Atlantic elasmobranch fisheries status. In the Mid-Atlantic, elasmobranch fisheries mainly target 4 species, that are usually landed as bycatch: the tope shark (Galeorhinus galeus) and the thornback ray (Raja clavata), captured mainly by local demersal artisanal fisheries, the blue shark (Prionace glauca) and the shortfin mako shark (Isurus oxyrinchus) captured by a more industrialised fleet, including those from foreign nations. Considering elasmobranchs life history traits and fishery history, caution is advised in the development of a management strategy focusing on these species, considering the Northeast Atlantic context and regional, local and national interests. 相似文献
14.
生态模型在渔业管理中的应用 总被引：2，自引：1，他引：1
随着人们对于海洋生态的认识逐渐深入,渔业等人类活动的影响受到了更多的关注,"基于生态系统的渔业管理"（EBFM）这一概念被越来越多的研究者和国际组织所接受。生态模型为EBFM的实践提供了科学的评估方法和技术工具。与单鱼种评估模型相比,生态模型更多地考虑了系统内的各种生态过程和作用机制,栖息地等环境条件的变化,以及生态系统整体的结构和功能等,依此来反映生态系统的动态变化。由于生态模型是多样化的,关注和涉及不同的目标对象、机制过程、模型结构和参数,本文按照生态模型所关注的生态层次和组分将其分为多物种模型、群落结构模型和生态系统模型3个类型,分析了各类模型的优劣点。本文进一步阐述了生态模型在渔业管理中的应用领域,以管理策略评估为中心的应用方式,以及实践中模型选择和构建所需要注意的问题,还探讨了生态模型中降低不确定性和提高预测能力的方法。 相似文献
15.
《Marine Policy》2017
Most fisheries for deep-water snappers, groupers and other demersal fishes in many countries and territories throughout the Indo-Pacific are data-poor and/or resource-poor. Current and emerging methods for obtaining important information on life history, ecological assessments, and stock assessments for these deep-water species were discussed at an international workshop in Perth, Western Australia in July 2016. The key issues raised included: (i) the ongoing need to adopt nascent methods for otolith sectioning and interpretation; (ii) the need for standardised international ageing protocols to be documented; (iii) the benefits of investigating otolith chronologies both for age validation and the influence of climate variability on fish populations; (iv) a need to investigate the ecological niches and requirements for deep-water fishes; (v) improved understanding of genetic stock structure/connectivity, diet and gene flow across a range of spatial scales; (vi) the need for an improved understanding of the performance and uncertainty associated with length- and age-based catch curves and spawning potential ratio stock assessments; and (vii) the issues and challenges in developing harvest strategies for deep-water data, and/or resource poor resources. Many new or refined strategic directions for further investigation were identified to resolve uncertainty in monitoring and assessment approaches to contribute toward more rigorous fisheries management arrangements. 相似文献
16.
《Marine Policy》2013
Many conventional management strategies have been demonstrated to be ineffective in achieving sustainable fisheries, and new approaches are required to overcome existing environmental, social and economic problems. Adaptive co-management represents the combination of a learning-by-doing approach (adaptive management) involving all related and legitimate stakeholders in the decision-making process (collaborative management). In this study, the relevant experiences from a fishery in southern Brazil are reported. The first section of the paper summarizes the broad history of national fisheries and their management. Then the southern Brazilian artisanal penaeid-trawl fishery is briefly described and the three main problems associated with the common gears used are discussed, including their (1) poor size and species selectivities, (2) poor efficiencies, and (3) their mechanical impacts on benthic habitats. Finally, a framework is proposed to address the environmental and socio-economic issues in the fishery and its implementation discussed via an adaptive co-management approach. 相似文献
17.
《Marine Policy》2017
A coupled population dynamics and economic model is applied to the purse seine anchovy-fishery in the Gulf of Cádiz. The model simulates the population dynamics, landings and profits on a probabilistic frame. These simulations are used to assess the biological and economic consequences of an individual quota management framework enveloped by a fixed Total Allowable Catch (TAC), the present strategy used to manage this stock in the Spanish fishery. Our results accurately indicate that this strategy magnifies the biological and economic vulnerabilities associated with the exploitation of the stock, thus jeopardizing the sustainability of this fishery. Alternative strategies, such as an adaptive TAC, are explored. The results indicate that even a basic implementation of an adaptive TAC seems more favorable than the present strategy in the necessary equilibrium between profits and sustainability. This paper provides tools and an assessment that may also be useful for other small pelagic fisheries. 相似文献
18.
Integrated fishery assessments are intended to take an integrated and wholistic view of fisheries management, to provide comprehensive systems-based evaluations of the sustainability of individual fisheries and their products. Using guidance derived from decision theory and management science, we develop 18 criteria to evaluate the likely effectiveness of nine integrated fishery assessment systems. The assessment systems do not consistently consider four key criteria: the socio-economic impacts of fisheries, the provision of food security, the local relevance of the assessment to the fishery under assessment, and the independent peer review of assessment outcomes. Other important areas of weakness include the lack of appropriate consultation processes relating to both the design of the assessment system and the outcomes of fishery assessments, and limitations in the quality of data and information used in assessments. Improvements will be needed in these areas across all the systems we evaluated if fishers, consumers, managers and other stakeholders are to be provided with consistently reliable assessment outcomes, and an assurance of the sustainability of capture fisheries. 相似文献
19.
《African Journal of Marine Science》2013,35(1):975-988
There are currently three dominant approaches to fisheries stock assessment: analysis of catch-at-age data; simple models of biomass dynamics (often called surplus production models) that rely only on catch and some index of abundance; and analysis of length frequency data. A key characteristic of all these methods is that they rely primarily on one type of data and ignore most of what is known about the biology of the species in question and what has been learned from fisheries elsewhere. Other information is sometimes included subjectively after the stock assessment is complete. The first major trend in assessment methods is developing ways of incorporating all that is known about the biology of a species into a single unified assessment procedure. The second major development is in methods of incorporating uncertainty in stock assessment, using statistical decision theory. At present few agencies have formal methods for treating the uncertainty inherent in stock assessment, and therefore uncertainty is often ignored. A number of trends in fisheries management are reviewed, including adoption of formal harvest strategies, recognition that fisheries management is a matter of decision-making and risk-taking, and the use of Monte-Carlo evaluation of fisheries management options. Future trends in stock assessment and management will likely include more attention to the behaviour of fishermen in response to regulations, more involvement of user-groups in decision-making, much more allocation of property rights, including complete privatization of some fisheries, and demand for evaluation of cost effectiveness of research and management activities. Threats to commercial fisheries as now known are discussed, including growing allocation to recreational and aboriginal users, environmentalists and the impact of aquaculture. 相似文献
20.
《Marine Policy》2014
Currently there is a strong interest in Cuba in improving the performance of the fisheries sector with respect to social, biological, and economic outcomes. Many important fishery resources appear to be overexploited, and previous fishery regulations have had mixed success in restoring fishery stocks. The current fishing pressure could also have adverse impacts on other valuable ecosystem services that support economic activities such as dive tourism and recreational fishing. A new State policy to expand cooperative enterprises to non-agricultural sectors provides an opportunity for fishery cooperatives to be created for the first time since the early years of the Cuban Revolution. This paper explores the potential ecological, social, and economic benefits of adopting fishery cooperatives as a co-management scheme for Cuba's marine fisheries. It concludes that well-designed fishery cooperatives can offer substantial benefits to the management of the fishery sector. Based on an analysis of the relative success of fishing cooperatives worldwide, guidelines are provided for the design of fishery cooperatives in Cuba. 相似文献