The expansion,limit and decline of the global marine fish catch

Catch of marine fish grew from after WW II–1989, at which point it stabilized. In 1996 it began to decline. It continues to decline now, at a time when earth's population is expected to reach 10 billion by 2050. Since the factors driving the increase are primarily the growth in income, population, technology of catching fish and ever increasing fishing effort, it is to be expected that the aggregate marine catch will continue to decline. This decline has important implications for marine ecosystems but primarily its importance relates to the human use of other global resources such as food, water and world's climate.     

An overview of marine fisheries management in China

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

我国海洋渔业地理信息系统发展现状

详细总结了我国海洋渔业地理信息系统的研究与应用现状,远洋渔业地理信息系统主要应用于金枪鱼、鱿钓业和秋刀鱼的资源分布、渔获量与渔场环境关系、渔情预报、渔场图绘制等方面,近海主要用于分析东海渔业资源分布和漂移特征、渔场环境分布、部分种类渔获量分布与环境关系及渔情预报等方面。除渔业资源与渔场领域外,渔业地理信息系统还被应用到渔船跟踪、捕捞违法行为判别、渔业信息发布和水产品查询,以及渔港建设等领域,国内学者在进行渔业地理信息系统技术应用的同时,还注重了其技术的研究及改进。     

世界海洋捕捞业发展概况、趋势及对我国的启示

由于海洋渔业资源的衰退,目前世界海洋捕捞业进入"零增长"的徘徊期。当前世界海洋捕捞业呈现以下发展趋势:海洋渔业资源争夺日益激烈,海洋捕捞业管理制度日益严格,世界海洋捕捞业产业转移趋势日趋明显,海洋捕捞业技术装备要求越来越高,国际社会越来越重视海洋捕捞业可持续发展。面对世界海洋捕捞业的发展趋势,我国应当继续发展资源养护型海洋渔业,从生态系统角度考虑海洋捕捞业管理措施,积极稳妥发展远洋渔业,参与国际渔业资源的开发,重视海洋捕捞业装备技术水平的提高。     

过度捕捞造成全球海洋渔业的产量损失评估

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.     

The changing face of global fisheries—The 1950s vs. the 2000s

Spatialized catch and effort data, representing the world's marine fisheries in the 1950s and the 2000s are presented in form of cartograms, i.e., global maps in which the surface areas of continents are made proportional to the magnitude of the annual catches and fishing effort by their fleets. This is complemented by an analysis of the flows of seafood between the continents in whose waters the fish were captured, in the 1950s and the 2000s, and the continents where fleets originated. Such broad-brush analyses of temporal changes and trade patterns are helpful to understand major trends of fisheries, which, are increasingly dominated by scarcity of fish, and competition, notably off the coast of West Africa, and in newly accessed polar waters.     

When plenty is not enough: an assessment of the white stumpnose (Rhabdosargus globiceps) fishery of Saldanha Bay,South Africa

White stumpnose Rhabdosargus globiceps is the main target of the linefishery in Saldanha Bay. Increased fishing pressure over the last three decades, particularly by the recreational sector, has led to concerns regarding sustainability of the local white stumpnose stock. The fishery was exceptionally productive between 2006 and 2008, with an estimated annual catch of 141.2 tonnes (t). Only 3% of boat outings surveyed were commercial boats targeting white stumpnose, yet this sector accounted for 39.3 t (31%) of the average annual catch. The recreational boat sector accounted for most of the catch (70.0 t), and the recreational shore sector the least (31.9 t). Commercial boat catch per unit effort (CPUE; 3.7 fish angler^–1 h^–1) was more than 10 times that of recreational boats (0.3 fish angler^–1 h^–1). White stumpnose catch length-frequency differed significantly (p < 0.01) between the fishing sectors, with the commercial sector retaining larger fish (34.7 cm [SD 5.9]) than the recreational boat (33.9 cm [SD 5.9]) and shore (30.4 cm [SD 5.8]) sectors. A decline in commercial CPUE (2000–2015) of approximately 40% and a concomitant severe decline (>95%) in survey data for juvenile white stumpnose CPUE (2007–2016) indicate that the current rate of exploitation is not sustainable. Recovery of the white stumpnose stock will require a decrease in fishing mortality. Possible management regulations include sector-specific effort limitations, extending the ‘no take’ marine protected area, reducing the recreational-sector bag limit to 5 fish person^–1 day^–1, implementing a commercial-sector bag limit, and increasing the minimum size limit to 30 cm TL.     

Assessing the significance of the economic impact of Marine Conservation Zones in the Irish Sea upon the fisheries sector and regional economy in Northern Ireland

This paper highlights the tension between advocacy for ‘Blue growth’ in maritime policy and efforts to safeguard future economic growth via the Marine Strategy Framework Directive. In 2015, policy-makers withdrew three of four proposed Marine Conservation Zones (MCZs) in the Irish Sea from consideration for designation, due to concerns that they could significantly impact on the fisheries sector in Northern Ireland because they overlap with prawn fishing grounds in the Irish Sea. Although research has quantified the potential impact upon fishing vessels, none has quantified the impact upon the fisheries sector nor assessed the significance of this impact. Arguably, MCZ designations (or lack thereof) based on the ‘significance’ of an impact require robust underpinning evidence. This paper reports the findings of an Economic Impact Assessment, which has quantified the impact of a decline in landings upon the Northern Ireland fisheries sector and regional economy (data which is currently absent from the evidence base for the MCZ designation process in England). It finds that this will incur job losses in three fishing ports in Northern Ireland, but is unlikely to have a significant impact upon Northern Ireland's fisheries sector and regional economy in terms of jobs and Gross Value Added (GVA). In the worst case, the resulting economic impact is a decrease of £1.05–1.12 m/year GVA in Northern Ireland, which is 1.1% of the contribution of fishing and fish processing to the regional economy. Economic significance assessments, using this methodology, may be useful in supporting the evidence base underpinning MCZ designation and other aspects of marine planning.     

Sea turtle bycatch to fish catch ratios for differentiating Hawaii longline-caught seafood products

Sea turtles can be incidentally caught in pelagic longline fishing gear targeting tuna and swordfish. Bycatch to fish catch (B/C) ratios can differentiate seafood based on sea turtle impacts. This study demonstrates the use of B/C ratios indexed to the weight of fish catch: (1) to report on the significant progress in reducing sea turtle bycatch in Hawaii's swordfish longline sector and (2) to compare Hawaii and other Pacific longline fisheries by number of sea turtle interactions per weight of catch. Hawaii's longline tuna fishery sets the benchmark of 1 sea turtle interaction per 190,000 kg of tuna caught.     

The impact of artisanal fishing on coral reef fish health in Hat Thai Mueang,Phang-nga Province,Southern Thailand

This study investigates whether there has been a decline in fish stocks of a coral reef in Thailand, and if so, whether that decline is due to small-scale fishing. The research methods used included fish sampling by UVC, interviews and questionnaires with key informants and artisanal fishers. The results confirmed that there has been a decline in piscivores and carnivores (though not herbivores), and the main perceived threat came not from artisanal but from commercial fishing. Recommendations are to replace the largely unrestricted fishery with a more regulated regime backed by effective enforcement.     

Quota concentration in the New Zealand fishery: Annual catch entitlement and the small fisher

New Zealand's quota management system (QMS) was introduced in 1986 to enhance the sustainability of New Zealand's fishery. This paper examines trends in quota and catch share concentration across a range of important fish stocks. It demonstrates that continuing concentration is occurring in the ownership of quota for deepwater species. At the same time there has been an increase in participation by small scale fishers in the inshore fishery. This appears to be driven by the introduction of the Annual Catch Entitlement (ACE) regime, allowing annual catch shares to be accessed at reduced transaction cost.     

Economic incentives for sustainable hilsa fishing in Bangladesh: An analysis of the legal and institutional framework

Bangladesh's hilsa shad (Tenulosa ilisha) comprises the largest single-species fishery in the country, constituting 11 per cent of the total catch and employing 2.5 million people directly or indirectly. Since 2003, following a sharp decline in catch figures, the hilsa fish has been the subject of a government conservation programme offering fishers economic incentives or payments for ecosystem services (PES). While PES schemes are widely used to conserve natural resources such as forests and watersheds, Bangladesh's programme is a rare example of PES for sustainable fishery management. Catch figures have improved since the programme was introduced; but concerns remain about fishers’ socioeconomic conditions and the long-term sustainability of Bangladesh's hilsa fishery. This paper analyses the conservation scheme's legal and institutional frameworks, identifying challenges to its design and implementation, and makes recommendations to overcome them.     

The potential use of predictions of recruitment success in the management of the South African anchovy resource

In the existing management procedure for the South African anchovy Engraulis capensis resource, an initial Total Allowable Catch (TAC) is set at the start of the fishing season in January, before the year's recruitment of 0-year-old fish, an important component of the catch, is known. Recruitment is therefore assumed to be equal to the observed median. This TAC may be revised in May or June, after the actual recruitment has been estimated. This procedure incorporates a risk that, if recruitment is below the median, the stock could be adversely depleted before the mid-year recruitment survey. A simulation approach is used in this paper to assess the possible benefits, in terms of average annual catch and interannual fluctuations in catch, of three different methods of predicting recruitment earlier in the season, if such methods were available. The results show that the average annual catch could be increased theoretically by up to 48 per cent if a very precise prediction (CV = 0,1) could be made at the start of the fishing season. In practice, more modest improvements of 21 per cent by prerecruit surveys undertaken in March each year, or 16 per cent by means of a two-class ordinal prediction with 70 per cent success, may be attainable. However, these improvements would result in increased interannual fluctuations in catch, a situation which may be detrimental to the fishing industry.     

Discards in North Sea fisheries: causes,consequences and solutions

Discards refer to that part of the catch returned to the sea during fishing operations. This study assesses the consequences, causes, and potential solutions to the discard problem using the example of North Sea fisheries. Fishermen's immediate objectives during fishing operations and the low confidence in projected gains from discard reduction measures have promoted use of unselective trawls while the poor enforcement of the quota system has exacerbated discard quantities. It is concluded that a reduction in discard rates is required for a long-term solution to the ecological and economic costs of discarding and the development of fishing opportunity incentives can promote the use of more selective fishing techniques.     

Responses and adaptation strategies of commercial and charter fishers to zoning changes in the Great Barrier Reef Marine Park

Fishers' responses to changes in resource access through the imposition of marine protected areas can be a critical factor influencing the likelihood of achieving management objectives.Face-to-face interviews with 114 commercial and charter fishers were conducted to investigate their responses and adaptation strategies to the increase in the size and number of no-take zones imposed by the 2004 Great Barrier Reef Marine Park zoning plan. Despite holding positive attitudes towards marine biodiversity protection, fishers were generally unsupportive of the new zoning plan 5 years after its implementation. Fishers' lack of support was related to the perception that they had not been adequately engaged in the rezoning process and the perception of significant impacts of the zoning plan on fishing businesses. Fishers generally believed that the new zoning plan had a negative impact on their access to productive fishing areas, the numbers of fish they catch, the profitability of their fishing business, and their personal income. In response to the new no-take zones, fishers tended to redistribute their fishing activity to locations closer to their home port, and to locations already known to them through their previous fishing, resulting in an increase in high density fishing locations within the park. Despite the impacts that fishers experienced, most reported that they have adapted their fishing activity and fishing business at least moderately well to the new zoning plan, suggesting that many of the impacts experienced by fishers might be short-term and may decline over time as fishers learn to adapt to the new zoning system. The information provided should prove valuable as a baseline for continued monitoring of the costs and benefits of the Great Barrier Reef Marine Park rezoning into the future.     

National comprehensive approaches for rebuilding fisheries in South Korea

Korea's coastal and offshore fisheries have experienced reduction in their catch in the early 2000. The amount of catch from coastal and offshore fisheries dropped from 1.7 million tons in 1986 to 1 million tons in 2004. To address such catch reduction, fish stock enhancement programs have been constantly developed and implemented. However, as fish stocks have been estimated to decrease since 2000 in spite of various management measures, the Korean Government genuinely acknowledges the necessity to enhance fisheries productivity through the recovery of depleted fish stocks. Based on such acknowledgement, a fish stock rebuilding plan (FSRP) combined with conventional fish stock enhancement programs was established in 2005. For stocks which have shown drastic decrease, a FSRP was set up and promoted. So far, 10 FSRPs have been established and operated, and plan is being made to expand them to 20 species by 2012. The result of pilot projects shows that stocks have been increasing after the introduction of FSRPs. For instance, the catch per unit effort (CPUE) of sandfish in the East Sea has increased from 0.44 in 2005 to 0.78 in 2011. Consequently, fishing income has increased by 15%. The key lessons learned during the implementation of FSRP are: the causes for the decrease of stock vary and are complicated and it is necessary to adjust and eliminate some conventional policies that could have unforeseen negative impacts on fish stocks. The FSRP-based fisheries management policy in Korea carries great significance, for it has changed the focus of policy from simply maintaining the status quo to stock recovery and it allows relevant stakeholders to get actively involved in the procedures of establishing and promoting the plan, leading to effective implementation of the plan. The current FSRP is operated with species, but if it can be gradually expanded to encompass the whole ecosystem, it will greatly contribute to more effective management and fish stock recovery for all species in offshore and coastal waters surrounding Korea.     

Assessment of IUU fishing for Southern Bluefin Tuna

Illegal, unreported and unregulated (IUU) fishing is recognized as one of the largest threats to the sustainability of the world's fisheries. This paper focuses on IUU fishing in the context of unreported catches by members or co-operating non-members of regional fisheries management organizations (RFMOs) and their implications for scientific assessments of stock status and management advice. A review of Japanese market statistics was undertaken in 2006 by an independent panel in relation to catches of southern bluefin tuna (SBT). Based on this review, the Commission for the Conservation of Southern Bluefin Tuna (CCSBT) concluded that very substantial and continuous unreported catches of SBT had been taken by longline vessels since at least the early 1990s. While uncertainty exists about the fleets contributing to these IUU catches, the assumption used within the CCSBT Scientific Committee is that a significant proportion of these were taken by Japanese longliners. Implications of these unreported catches for the stock assessments by RFMOs are discussed in light of the central role that Japanese vessel reported data have in the assessment of the world's tuna and billfish stocks. Results indicate that it is plausible that the unreported catches of SBT stem from the misreporting of catches as other tuna species and/or the location of fishing effort. The magnitude and extended period of the unreported SBT catches highlight the wide-spread risks of relying on fishery dependent logbook data in the absence of verification. An urgent need exists for minimum standards of verification of catch, effort and landing statistics for use in scientific assessments. The fisheries science community needs to be more pro-active in the development of such standards and the implementation of independent monitoring and verification. In addition, there is a need to reform the operation of the scientific bodies of RFMOs in terms of transparency, the treatment of uncertainty and the burden of proof if they are to be effective in providing objective scientific advice consistent with the intent of international agreements.     

Long-term trends in the recreational shore-fishery for elf Pomatomus saltatrix (Pomatomidae) along the KwaZulu-Natal coast,South Africa

Elf Pomatomus saltatrix account for between 28% and 80% of the annually recorded recreational shore-angling catch in KwaZulu-Natal, South Africa, and have been subjected to various management regimes over the past 33 years. Management of the elf fishery was amended in 2005 to reduce fishing mortality and enhance egg production, following an assessment in 1997, which considered the elf stock to be overexploited and in need of rebuilding. A compromise was reached whereby the bag limit was reduced from five to four elf per angler per day, but the closed season was shortened, allowing an extra month of fishing for elf. A total of 33 years of recreational elf catches recorded on the National Marine Linefish System was investigated for any long-term trends and how they related to management of this species. Over 3 million angler-outings from the recreational shore-fishery in KZN were analysed, including more than 1.5 million elf in the catch. Despite the fast growth of elf and the latest management intervention seven years ago, which was based on a rigorous investigation of life-history parameters, the present study showed no evidence of an improvement in catch rate. It could not be determined whether this was due to a reduction in the bag limit, which would naturally reduce catch rates or whether other factors, including the shortened closed season, had been detrimental to elf stocks. Some shortfalls in the management of elf are discussed and possible reasons for the great variability in catches, which complicated the assessment of trends, are explored.     

Eco-labeling of seafood: Does it affect the harvesting patterns of Norwegian fishermen?

The aim of this paper is to compare the criteria for eco-labeling of wild-caught fish in the Norwegian eco-certified fisheries, and to study if these eco-labels affect the harvesting patterns of Norwegian fishermen. The eco-labels Marine Stewardship Council (MSC), KRAV and Friend of the Sea (FOS) as applied in 2009 were studied. In this study, the harvesting patterns are defined by using the following parameters: season, catch area, size of fishing vessel, gear type, bycatch, location of landing site and distance to the fishing ground. KRAV had more specific criteria than did MSC and FOS in specific fisheries regarding time of the fishing effort, catch area, size of fishing vessels, gear type (e.g. hook size, and the use of beam trawlers was not permitted) and distance to the fishing ground. The findings show that few of the eco-label requirements influenced these aspects in Norwegian fisheries.