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1.
In recent decades, sea cucumber fisheries have rapidly expanded worldwide to meet rising demand in Asian markets. Catch trends have often followed a boom-and-bust trajectory and skyrocketing sea cucumber value has often spurred fishery development that outpaced adequate biological research for informed stock assessment. Currently, the dive fishery for Giant red sea cucumber (Parastichopus californicus) in British Columbia, Canada is considered moderately exploited. However, basic population parameters such as recruitment and mortality rates are still largely unknown, creating important sources of uncertainty in the fishery׳s stock assessment model. This study presents the results of an interview-based survey of experienced commercial harvesters׳ (1) perceptions of local trends in sea cucumber abundance, size, and fishing effort (CPUE), and (2) perceptions of management efficacy. The majority of harvesters perceived abundance (14/20) and CPUE (15/20) to have declined over their careers, and half of the harvesters reported decreased sea cucumber size. The harvesters most commonly cited overfishing as the most pressing problem facing the fishery (13/20), and the majority felt that Fisheries and Oceans Canada (DFO) needed to lower licence and/or area quotas to avoid further declines. Despite many knowledge gaps in the fishery, almost all harvesters (16/20) perceived that they are not adequately consulted and their concerns are not adequately considered by DFO. These results suggest a disjoint between DFO forecasts and perceived local sea cucumber trends, and highlight that the fishery may lack a resource-rights framework with adequate checks to decouple fishing pressure from increasing global market value and demand. Maintaining the long-term health of the BC sea cucumber fishery may depend on working more closely with harvesters to inform future management decisions and, ideally, moving towards a harvester-owned-and-operated licencing system that can better integrate the feedback that comes from attachment to place.  相似文献   

2.
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   

3.
Fishers from several ethnic groups on islands in eastern Indonesia seasonally fish for sea cucumbers at Scott Reef in Australia's Exclusive Economic Zone in the Timor Sea. Despite evidence suggesting that sea cucumbers are severely over-exploited fishers continue to voyage to the reef. How the traditional fishery operates under this condition and more broadly what economic drivers cause fishers to make the long and arduous voyage is vital to understanding this small-scale fishery and developing appropriate strategies for management. This study is the first to investigate these dynamic livelihood aspects using semi-structured interviews and fishers’ voluntarily recorded data on their catches, costs of fishing and the sales of those catches and income received over a six year period. The study demonstrated that costs, borrowings, and revenues differed between crews, leading to widely varying profits. Nevertheless, every crew that recorded the sale of their catches made a profit. Rapidly appreciating prices for their sea cucumber harvest, predominantly comprising low value species, was critical to maintaining the fishery's profitability. The income earned by some crews and boat owners were far greater than those potentially available to them through other livelihood strategies such as agriculture, coastal fisheries or trade opportunities. This study also suggests the depletion of high value sea cucumber species is ongoing. This Indonesian sea cucumber fishery at Scott Reef illustrates the linkages between stock sustainability, fishers’ livelihood outcomes, and the burgeoning Asian demand for sea cucumbers and the findings can inform the current management discourse on this small-scale transboundary fishery.  相似文献   

4.
Many fish stocks in the world are depleted as a result of overexploitation, which reduces stock productivity and results in loss of potential yields. In this study we analyzed the catch trends and approximate thresholds of sustainable fishing for fished stocks to estimate the potential loss of catch and revenue of global fisheries as a result of overexploitation during the period of 1950–2010 in 14 FAO fishing areas. About 35% of stocks in the global marine ocean have or had suffered from overexploitation at present. The global catch losses amounted to 332.8 million tonnes over 1950–2010, resulting in a direct economic loss of US$298.9 billion(constant 2005 US$).Unsustainable fishing caused substantial potential losses worldwide, especially in the northern hemisphere.Estimated potential losses due to overfishing for different groups of resources showed that the low-value but abundant small-medium pelagics made the largest contribution to the global catch loss, with a weight of 265.0 million tonnes. The geographic expansion of overfishing not only showed serial depletion of world's fishery resources, but also reflected how recent trends towards sustainability can stabilize or reverse catch losses.Reduction of global fishing capacity and changes in fishery management systems are necessary if the long-term sustainability of marine fisheries in the world is to be achieved.  相似文献   

5.
The management and governance of shared stocks have long been identified as a challenge to achieve long-term sustainability in fisheries. This is the situation of fisheries in the Amazon basin, a region shared by nine countries. This paper provides an overview of the social-ecological outcomes and management implications of sharing fish stocks among countries with different public policies, taking the valuable Amazonian ornamental silver arawana (Osteoglossum bicirrhosum) trade as a case study. Specifically, it (i) presents and discusses the policies of Colombia, Peru and Brazil for the silver arawana fishery, and how these are conducive for the successful management of this shared transboundary fishery; and (ii) analyzes the market for the ornamental silver arawana and how it affects the ability to sustainably manage the fishery. The interplay between the multiple environmental, economic and social dimensions involved in the ornamental silver arawana fishery affects the sustainability of this species even in Brazil, where this fishing is forbidden but still illegally caught by Colombians and Peruvians. Among the factors that make fisheries policies inefficient in this region are: (i) incongruent policies between the countries and institutions with low organizational capacity to accomplish the established policies; (ii) environmental heterogeneity of Amazonian aquatic systems, which requires local and adaptive measures; and (iii) complex socio-economic relationships in the live-fish trade business. Legally binding efforts to reduce problems derived from shared fish stocks are an urgent need and should be addressed by the multilateral organizations created for the Amazonian sustainable development.  相似文献   

6.
This study, carried out in five fishing communities along the Kenyan coast, examined fisheries-derived income of fishers and traders in two different invertebrate fisheries (octopus and sea cucumber) and tested if differences in global market integration of these two products could explain differences in income inequalities among actors involved in the two fisheries. The structure of the value chains was mapped, differences in income between fishers and traders tested, and income inequalities among actors in each fishery examined. Although the octopus fishery included a greater diversity of actors and thereby provides income to a larger group of people, income inequality in this fishery was higher among fishers and traders than in the sea cucumber fishery. Thus, the often cited relationship between increasing market integration and income inequality may require a re-evaluation and a more nuanced treatment.  相似文献   

7.
The cod stocks in the Baltic Sea are important not only for fisheries but for the entire ecosystem utilized by numerous stakeholders around the coast. All such activities have economic values. In this note the economics of the Swedish Baltic Sea cod fishery is estimated in relation to the sector's interaction with other users of the Baltic Sea ecosystem. The results show a negative resource rent for the fishery, € −5 million without public expenses (subsidies and administrative costs), and € −13 million including public expenses. The interactions between the fisheries and tourism, seal population, carbon dioxide emissions, recreational fishing, and discards are discussed, and when monetary estimates are available these are related to the estimated resource rent.  相似文献   

8.
It has been suggested that the fisheries management process with multiple, informed stakeholders and socio-economic, political, and scientific complexity can be considered a governance network. This exploratory study applied communication network analysis (CNA) measures and methods to assess two cases of US federal fishery management in the Northwest Atlantic—Atlantic herring and sea scallop. Through questionnaires and interviews, CNA maps were constructed and quantitative measures of network structure and function (density, weighted average path length) and centrality measures for individual network members (degree, betweenness) were derived using InFlow software. The results show that fishery governance networks are horizontally and vertically integrated across levels of government and public–private–nonprofit sectors. The findings validated existing understanding of fisheries management as a contested, competitive management context among stakeholders, and provided new insights about the effectiveness of information sharing across the network and the critical role of bridgers connecting disparate subgroups. Fisheries management can be conceptualized and analyzed as governance networks, and the paper discusses additional research questions, refinements needed for application of the research methods, and ramifications for managers (e.g., can resource managers manage networks).  相似文献   

9.
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   

10.
This paper surveys the current state and major trends in global fisheries; the environmental and social dimensions of fisheries; and explains how the international community has tried to meet the policy challenges associated with oceans and fisheries. The ocean and the freshwater ecosystems of the world make significant contributions to people's well-being via the many vital social and environmental services they provide (for example, food and nutrition, employment and incomes, carbon cycling and sequestration). The impact that the increase in fishing since the 1950s has had on wild fish stocks, and the significant increase in aquaculture production in the 20th century, have resulted in severe environmental impacts. This has significant effects on marine ecosystems and the health of oceans. The erosion of the resource undermines communities' long-term interests, including food security, employment, and income. Attempts by the global community to address challenges of sustainable production by improving the governance and management of fisheries resources range from national management of fisheries resources, to regional fisheries management organisations (RFMOs) for international fisheries stocks. These attempts have not always successfully met the challenge of balancing current and future use of fisheries.  相似文献   

11.
Decline in tuna fish stocks due to weak enforcement of regulations on fishing effort poses a challenge to the sustainability of tuna fishery. Intervention programs to address this problem require an understanding of the operational behaviour of the fishers and how various socioeconomic factors may impact fishers’ decisions to continue or discontinue their fishing efforts. A semi-structured interview questionnaire was developed to find whether fishers are willing to keep, change their fishing strategies or exit the fishery if their regular catch will decline by half. Boat captains, assistant boat captains and crew from General Santos City, Lupon, Mati City and Governor Generoso in the Philippines (n=293) were purposively selected for interviews. Results show that fishers from General Santos City with ancillary industries and Lupon with fewer economic development are more willing to adapt or change their fishing strategies. The catch value or price was found to have a strong influence on the likelihood that anchored FAD tuna fishers will adapt or change their fishing strategy when their catches decline. Fishers whose catch fetched a price of PhP 151.00 (US$ 3.48) and above Php 200 (US$ 4.61) have 80% probability to change their fishing strategy. The proportion of catch sold also had a high influence on the decisions to adapt in the fishery with fishers selling 36% and 73% of their catches have 100% and 70% probability to adapt. The results suggest a reluctance to exit the fisheries even when tuna fishing is no longer economically viable, fishers opt to adapt.  相似文献   

12.
Up to one-third of commercial fishery stocks may be overfished at present. By analyzing catch trends and applying an empirical relationship derived from stock assessments, this article tracks the geographic spread of overfishing at the country level in terms of lost catch and lost revenue, from the start of industrialized fishing in 1950-2004. The results tell a cautionary tale of serial depletion to meet the ever-rising demand for fish. Examining country losses with respect to fishery management reveals that overcapacity and excess fishing effort are widespread, but also that recent trends towards sustainability can stabilize or reverse losses (e.g. for Norway, Iceland, the US, Canada, Australia, and New Zealand). Global trade effectively masks the successive depletion of stocks, so that without decisive action to reduce fishing effort, many more stocks will suffer and undernourishment impacts for the major exporting, food-deficit nations will only magnify.  相似文献   

13.
The spatial structure of fishery resources influences stock dynamics and finally the fishery. Therefore, this aspect should be included as a key topic in the assessment and management of fisheries. The fishery of the sea urchin Paracentrotus lividus in Galicia has been used as case study to demonstrate how the mismatch between biological, fishery and management scales causes failures in the governance, giving rise to over-exploitation. P. lividus is spatially distributed in nested biological units: patches, micro-stocks, local populations and metapopulations. Fishing operations are local exploiting micro-stocks; however management units in Galician comprise usually more than one local population. This pattern allows the depletion of several micro-stocks without any short-term signals in the exploitation rates over the complete managed territory. Management units should be redefined according to the boundaries of the local populations. In addition, the implementation of reserve networks or a rotation system could allow to effectively managing the resource at a fine-scale. Any of both regulations could also compensate the inverse density dependence that regulates recruitment and fecundity in this species.  相似文献   

14.
The vulnerabilities of fishing communities to climate and environmental change represent major issues for the governance of fisheries resources which have a direct effect on human security, livelihoods and rights. This paper explores the dynamics of social-ecological systems in the estuary of the Patos Lagoon in southern Brazil. The paper identifies key factors that increase and/or minimize the vulnerabilities of the fishing communities in this lagoon with the objective of understanding: (a) the degree to which fishing communities are able to build adaptive and learning capacities to minimize/reduce vulnerabilities and maintain their livelihoods; and (b) how and under what circumstances external and internal factors may influence and disrupt the social-ecological resilience in this lagoon system. Results show that fishing communities with a higher degree of self-organization are able to create ways to minimize their vulnerability to adverse climatic conditions. However, only a few communities have developed adaptive mechanisms to cope with the influence of climate on resource abundance and availability. Little external institutional support for small-scale fishing communities, erosion of their traditional resource use systems and decreasing fish stocks in recent decades have all led to a gradual increase in the vulnerability of fishing livelihoods in this lagoon. The uncertainties associated with climate are related to increasing vulnerability and influence the degree of resource conservation and exploitation. The lack of public policies to deal with the impact of climate variability on the livelihoods of fishing communities and the presence of weak institutions in resource governance represent major threats to the social security of fishers in this region.  相似文献   

15.
This study presents the response of fisheries management to the extreme climatic events that affect marine capture fisheries and mariculture in Taiwan. Two regional approaches that can be applied universally to help capture fisheries and mariculture adapt to extreme weather events are also proposed. In the winter of 2008, an anomalously strong and continuous northeasterly wind caused by a La Niña event drove the cold China Coastal Current southward to penetrate the southern Taiwan Strait, and a portion of this current intruded eastward to the southern Penghu Archipelago. The cold current intrusion appreciably damaged marine aquaculture and the wild fish population, causing the death of more than 73 t of wild fish and 80% of cage aquaculture fish at the Penghu Islands. This extremely cold seawater event occurred between late January and the beginning of February 2008. To recover fishery resources around the waters of Penghu, fishery-related agencies adapted recovery measures over 3 years starting in April 2008 that included hatchery juvenile release, environmental monitoring, fishery subsidies, and ecological field investigations. This study suggests that responding to extreme climatic influences on fisheries and mariculture should include (1) establishing an early warning system by connecting fisheries agencies and marine research institutions to assist decision makers in performing time-adaptive measures, (2) temporarily suspending fishing activities after the occurrence of a natural disaster to help recover fishery resources and ecosystems, (3) altering the governance of farming fishing right so that fish farmers can temporarily transfer their aquaculture cages from high-risk areas to waters outside the influence of extreme weather events, and (4) continually filing surveys to understand the recovery status of marine ecosystems.  相似文献   

16.
In determining the importance of fisheries sustainability indicators, stakeholders’ interest plays a defining role in the fisheries management practices. The indicator based tools such as RAPFISH have been available for sustainability assessment of fishery resources. In the present study, procedures to validate the pre-selected RAPFISH, which is a multidisciplinary indicator based evaluation tool for measuring the sustainability of fishery resources, are applied. The sustainability indicators were subjected to validation process based on feedback from resource owners, users and experts, using Multi-Criteria Analyses such as Weighted Sum Model and Analytic Hierarchy Process. Based on the validation results, suggestions have been made to improve methodology and its effective application in practice. This paper demonstrates RAPFISH as a potentially effective multidisciplinary tool for evaluation of sustainability of fishery resources.  相似文献   

17.
剩余产量模型在不同渔业中的应用   总被引：4，自引：0，他引：4  
剩余产量模型因其简单和所需数据较少的特点为渔业资源评估广泛采用.本文应用目前常用的四种剩余产量模型对五种渔业下的渔业生物种群及北大西洋箭鱼种群xiphias gladius评估效果作了比较.四种剩余产量模型在渔业1中的评估效果较好,而在渔业2中的效果较差;Schnute模型在充分捕捞的渔业,如渔业3、4、5,尤其是在低生物量的渔业3中评估效果较好,但不适合评估未充分捕捞的渔业.Walters-Hilborn模型(W-H模型)适用于各种渔业,尤其是渔业1、4、5.在过度捕捞渔业中如渔业3、4,模型对参数q的估计较其它参数接近真值.在北大西洋箭鱼(xiphias gladius)渔业的评估中,W-H模型对MSY的估计约为14000吨,接近于Prager(1996)的结果.  相似文献   

18.
Positioning fisheries in a changing world   总被引：1，自引：1，他引：0  
Marine capture fisheries face major and complex challenges: habitat degradation, poor economic returns, social hardships from depleted stocks, illegal fishing, and climate change, among others. The key factors that prevent the transition to sustainable fisheries are information failures, transition costs, use and non-use conflicts and capacity constraints. Using the experiences of fisheries successes and failures it is argued only through better governance and institutional change that encompasses the public good of the oceans (biodiversity, ecosystem integrity, sustainability) and societal values (existence, aesthetic and amenity) will fisheries be made sustainable.  相似文献   

19.
Conventional top-down, exogenous approaches to fisheries management have been ineffective in more traditional and small-scale fisheries. Yet, there remains little understanding of the effectiveness of alternative approaches. This case-study of small-scale fisheries in the Comoros examines how effective local fishing associations are at managing common fisheries resources, and provides some understanding of the underlying characteristics of effectiveness. Emphasis is placed on assessing governance effectiveness according to characteristics appropriate within the local context, and on suggesting ways to enhance local institutional strength and capacity to manage resources. Qualitative methods were used to collect data on local governance structures and management tools, fishers’ knowledge and beliefs, and perceptions of the status of fisheries resources in four major fishing villages on the island of Ngazidja. Results show that fisheries management in the Comoros is informally shared between the State fisheries department, a national fishing syndicate, and village fishing associations. Village fishing associations play an active role in fisheries management by collectively designing, monitoring, and enforcing local regulations. Compliance with local regulations is high, primarily due to participatory decision-making, community-monitoring, and strong feelings of solidarity among fishers. Perceptions of the benefits of these regulations are also high. This suggests that by working within these pre-established informal management systems, collective governance of common pool resources can be achieved within communities, and feelings of empowerment and shared responsibility among resource users can lead to effective management practices.  相似文献   

20.
Developments in fisheries governance in recent decades—notably the 1982 United Nations Convention on the Law of the Sea and its implementing agreements—have established a framework of principles, standards, institutions and regulations that is broader and more complex than traditional fisheries management, which has generally focused on individual target species. As this framework has evolved, a number of seafood eco-labelling schemes have also developed. These schemes aim to identify well-managed fisheries and give competitive advantage to their products, thus translating the environmental awareness of consumers into direct support for sustainable fishing practices. This paper evaluates a number of these schemes in the context of international fisheries governance principles and considers the conservation benefits that may result from sustainability certification of Pacific tuna fisheries. The paper briefly summarises developments in eco-labeling of Pacific tuna fisheries in relation to the evolution of fisheries management, where focus has shifted from the maximum sustainable yield of individual tuna species to ecosystem-based approaches that directly consider the broader environmental impacts of fishing. The paper discusses two different ‘Dolphin Safe’ eco-labels, the third-party scheme of the Earth Island Institute and the intergovernmental scheme of the Agreement on the International Dolphin Conservation Program, and two broader eco-labels offering sustainability certification of fisheries, ‘Friend of the Sea’ and the ‘Marine Stewardship Council’. The role played by seafood-industry associations with sustainability claims, such as the International Seafood Sustainability Foundation, is also considered.  相似文献   

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