Marine Capture Fisheries Research Articles

Bycatch governance and best practice mitigation technology in global tuna fisheries

Overexploitation of bycatch and target species in marine capture fisheries is the most widespread and direct driver of change and loss of global marine biodiversity. Bycatch in purse seine and pelagic longline tuna fisheries, the two primary gear types for catching tunas, is a primary mortality source of some populations of seabirds, sea turtles, marine mammals and sharks. Bycatch of juvenile tunas and unmarketable species and sizes of other fish in purse seine fisheries, and juvenile swordfish in longline fisheries, contributes to the overexploitation of some stocks, and is an allocation issue. There has been substantial progress in identifying gear technology solutions to seabird and sea turtle bycatch on longlines and to direct dolphin mortality in purse seines. Given sufficient investment, gear technology solutions are probably feasible for the remaining bycatch problems. More comprehensive consideration across species groups is needed to identify conflicts as well as mutual benefits from mitigation methods. Fishery-specific bycatch assessments are necessary to determine the efficacy, economic viability, practicality and safety of alternative mitigation methods. While support for gear technology research and development has generally been strong, political will to achieve broad uptake of best practices has been lacking. The five Regional Fisheries Management Organizations have achieved mixed progress mitigating bycatch. Large gaps remain in both knowledge of ecological risks and governance of bycatch. Most binding conservation and management measures fall short of gear technology best practice. A lack of performance standards, in combination with an inadequate observer coverage for all but large Pacific purse seiners, and incomplete data collection, hinders assessing measures' efficacy. Compliance is probably low due to inadequate surveillance and enforcement. Illegal, unreported and unregulated tuna fishing hampers governance efforts. Replacing consensus-based decision-making and eliminating opt-out provisions would help. Instituting rights-based management measures could elicit improved bycatch mitigation practices. While gradual improvements in an international governance of bycatch can be expected, market-based mechanisms, including retailers and their suppliers working with fisheries to gradually improve practices and governance, promise to be expeditious and effective.

Food security and marine capture fisheries: characteristics, trends, drivers and future perspectives

World population is expected to grow from the present 6.8 billion people to about 9 billion by 2050. The growing need for nutritious and healthy food will increase the demand for fisheries products from marine sources, whose productivity is already highly stressed by excessive fishing pressure, growing organic pollution, toxic contamination, coastal degradation and climate change. Looking towards 2050, the question is how fisheries governance, and the national and international policy and legal frameworks within which it is nested, will ensure a sustainable harvest, maintain biodiversity and ecosystem functions, and adapt to climate change. This paper looks at global fisheries production, the state of resources, contribution to food security and governance. It describes the main changes affecting the sector, including geographical expansion, fishing capacity-building, natural variability, environmental degradation and climate change. It identifies drivers and future challenges, while suggesting how new science, policies and interventions could best address those challenges.

Economic impact of ocean fish populations in the global fishery

Our goal in this paper is to estimate the total output in an economy that is currently dependent (at least partially) on current fisheries output. We therefore applied the Leontief technological coefficients at current production and then estimate total output supported throughout the economy at the current level of production. Estimates of gross revenue from capture fisheries suggest that the direct value of output for this sector is US $80–85 billion annually (Sumaila et al., Journal of Bioeconomics 9(1):39–51, 2007; Willmann et al., The Sunken Billions, World Bank, FAO, Washington DC, Rome, 2009). However, as a primary or a potential economic base industry, there are a vast number of secondary economic activities—from boat building to international transport—that are supported by world fisheries, yet these related activities are rarely considered when evaluating the economic impact of fisheries. This study applies an input–output methodology to estimate the total direct, indirect, and induced impact of marine capture fisheries on the world economy. While results suggest that there is a great deal of variation in fishing output multipliers between regions and countries, when we apply the output multipliers to the capture fisheries sector at the global level, we find that significant indirect and induced effects place the impact of this sector to world output nearly three times larger than the value of landings at first sale, at between US $225 and 240 billion per year.

Climate change and the Antarctic marine ecosystem: an essay on management implications

AbstractIn this paper we review evidence for, and anticipated consequences of, climate change in Antarctic marine communities, examining the potential impacts on invertebrates and vertebrates alike and exploring plausible outcomes for species, with examples principally from the Antarctic literature. We suggest that industries with the greatest potential to aggravate climate change impacts on marine communities are marine capture fisheries. In the Southern Ocean, harvesting is governed under the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR). CCAMLR espouses an ecological management framework and so has the capacity to mitigate harvesting impacts such that they do not worsen impacts from climate change. We discuss some of the implications of climate change and advocate that CCAMLR address certain key issues if it is to fulfil its international obligations. It will be essential for CCAMLR to determine relative risks (uncertainties), impacts and timescales, of various processes consequent on climate change. Such risk assessments should be feasible with current knowledge and should provide a focus for future work. We believe it will be important to prioritize issues that reduce impacts and uncertainties by the greatest degree, and propose that future plans should involve shared responsibility (e.g. with SCAR etc.) for each of the risks described.

Adaptation to climate change in marine capture fisheries

This paper responds to the challenge of how and when to adapt marine capture fisheries to climate change by (1) providing a set of fisheries policy options to climate change; (2) developing a risk and vulnerability assessment and management decision-making framework for adaptation; and (3) describing the possible strategies and tactics for ex ante and ex post climate adaptation in the marine environment. Its contributions include (1) a discussion of how management objectives and instruments influence resilience and adaptation; (2) a decision-making process to assess vulnerabilities to climate change and to manage adaptation responses; (3) an inter-temporal framework to assist decision-makers on when to adapt; (4) a risk and simulation approach to confront the uncertainties of the possible losses due to climate change and the net benefits of adaptation; (5) an explanation of how adaptive co-management can promote flexible adaptation responses and also strengthen adaptation capacity; and (6) a selection of possible ‘win–win’ management actions.

Marine Fisheries Management in a Changing Climate: A Review of Vulnerability and Future Options

Marine capture fisheries are an important source of protein globally, with coastal and oceanic fish providing a rich source of essential fatty acids, vitamins, and minerals. Fisheries also support economies and important social structures in many nations, particularly developing nations (Allison et al., 2009). Marine fisheries are under increasing threat from climate change, with climate change now identified as the latest threat to the world's fast declining fish stocks (UNEP, 2008; Cochrane et al., 2009). Marine fisheries will be exposed to increasing sea surface temperatures, ocean acidification, sea level rise, increasing storm intensity and altered ocean circulation, and rainfall patterns that will affect target species through a range of direct and indirect mechanisms. The sensitivity of fish stocks to these changes will determine the range of potential impacts to life cycles, species distributions, community structure, productivity, connectivity, organism performance, recruitment dynamics, prevalence of invasive species, and access to marine resources by fishers. Many fisheries are already experiencing changes in target species diversity and abundance, species distribution, and habitat area, as well as loss of fishing effort due to intensifying storms (Johnson and Marshall, 2007; Hobday et al., 2008; UNEP, 2008). Using a vulnerability assessment framework, we examine the level of vulnerability of marine fisheries to climate change and the factors that will temper vulnerability, such as adaptive capacity. Assessing fisheries vulnerability to climate change is essential to prioritize systems in greatest need of intervention, understand the drivers of vulnerability to identify future research directions, and more importantly, to review current fisheries management with the view to develop management responses that will be effective in securing the future sustainability of marine fisheries.

Responsible Aquaculture and Trophic Level Implications to Global Fish Supply

Hunger and malnutrition remain among the most devastating problems facing the world's poor and needy, and continue to dominate the health and well-being of the world's poorest nations. Moreover, there are growing doubts as to the long-term sustainability of many existing food production systems, including capture fisheries and aquaculture, to meet the future increasing global demands. Of the different agricultural food production systems, aquaculture (the farming of aquatic animals and plants) is widely viewed as an important weapon in the global fight against malnutrition and poverty, particularly within developing countries where over 93% of global production is currently produced, providing in most instances an affordable and a much needed source of high quality animal protein, lipids, and other essential nutrients. The current article compares for the first time the development and growth of the aquaculture sector and capture fisheries by analyzing production by mean trophic level. Whereas marine capture fisheries have been feeding the world on high trophic level carnivorous fish species since mankind has been fishing the oceans, aquaculture production within developing countries has focused, by and large, on the production of lower trophic level species. However, like capture fisheries, aquaculture focus within economically developed countries has been essentially on the culture of high value-, high trophic level-carnivorous species. The long term sustainability of these production systems is questionable unless the industry can reduce its dependence upon capture fisheries for sourcing raw materials for feed formulation and seed inputs. In line with above, the article calls for the urgent need for all countries to adopt and adhere to the principles and guidelines for responsible aquaculture of the FAO Code of Conduct for Responsible Fisheries.

Large‐scale redistribution of maximum fisheries catch potential in the global ocean under climate change

AbstractPrevious projection of climate change impacts on global food supply focuses solely on production from terrestrial biomes, ignoring the large contribution of animal protein from marine capture fisheries. Here, we project changes in global catch potential for 1066 species of exploited marine fish and invertebrates from 2005 to 2055 under climate change scenarios. We show that climate change may lead to large‐scale redistribution of global catch potential, with an average of 30–70% increase in high‐latitude regions and a drop of up to 40% in the tropics. Moreover, maximum catch potential declines considerably in the southward margins of semienclosed seas while it increases in poleward tips of continental shelf margins. Such changes are most apparent in the Pacific Ocean. Among the 20 most important fishing Exclusive Economic Zone (EEZ) regions in terms of their total landings, EEZ regions with the highest increase in catch potential by 2055 include Norway, Greenland, the United States (Alaska) and Russia (Asia). On the contrary, EEZ regions with the biggest loss in maximum catch potential include Indonesia, the United States (excluding Alaska and Hawaii), Chile and China. Many highly impacted regions, particularly those in the tropics, are socioeconomically vulnerable to these changes. Thus, our results indicate the need to develop adaptation policy that could minimize climate change impacts through fisheries. The study also provides information that may be useful to evaluate fisheries management options under climate change.

Rebuilding Global Fisheries

After a long history of overexploitation, increasing efforts to restore marine ecosystems and rebuild fisheries are under way. Here, we analyze current trends from a fisheries and conservation perspective. In 5 of 10 well-studied ecosystems, the average exploitation rate has recently declined and is now at or below the rate predicted to achieve maximum sustainable yield for seven systems. Yet 63% of assessed fish stocks worldwide still require rebuilding, and even lower exploitation rates are needed to reverse the collapse of vulnerable species. Combined fisheries and conservation objectives can be achieved by merging diverse management actions, including catch restrictions, gear modification, and closed areas, depending on local context. Impacts of international fleets and the lack of alternatives to fishing complicate prospects for rebuilding fisheries in many poorer regions, highlighting the need for a global perspective on rebuilding marine resources.

Conservation of Marine Megafauna through Minimization of Fisheries Bycatch

Many populations of marine megafauna, including seabirds, sea turtles, marine mammals, and elasmobranchs, have declined in recent decades due largely to anthropogenic mortality. To successfully conserve these long-lived animals, efforts must be prioritized according to feasibility and the degree to which they address threats with the highest relative impacts on population dynamics. Recently, Wilcox and Donlan (2007, Frontiers in Ecology and the Environment) and Donlan and Wilcox (2008, Biological Invasions) proposed a conservation strategy of "compensatory mitigation" in which fishing industries offset bycatch of seabirds and sea turtles by funding eradication of invasive mammalian predators from the terrestrial reproductive sites of these marine animals. Although this is a creative and conceptually compelling approach, we find it flawed as a conservation tool because it has narrow applicability among marine megafauna, it does not address the most pervasive threats to marine megafauna, and it is logistically and financially infeasible. Invasive predator eradication does not adequately offset the most pressing threat to most marine megafauna populations--fisheries bycatch. For seabird populations, fisheries bycatch and invasive predators infrequently are overlapping threats. Invasive predators have limited population-level impacts on sea turtles and marine mammals and no impacts on elasmobranchs, all of which are threatened by bycatch. Implementing compensatory mitigation in marine fisheries is unrealistic due to inadequate monitoring, control, and surveillance in the majority of fleets. Therefore, offsetting fisheries bycatch with eradication of invasive predators would be less likely to reverse population declines than reducing bycatch. We recommend that efforts to mitigate bycatch in marine capture fisheries should address multiple threats to sensitive bycatch species groups, but these efforts should first institute proven bycatch avoidance and reduction methods before considering compensatory mitigation.

Economic Viability of Small-scale Marine Capture Fisheries in the Bonny Area, Rivers State, Nigeria

This study describes the findings of a research project on economic viability of smallscale marine capture fisheries in the Bonny area, Rivers State, Nigeria. The study was designed to provide baseline economic information on small-scale capture fisheries. Small-scale fisheries are often the main drivers in the rural economy, accounting for nearly 50% of the global capture fisheries production, and cater primarily to direct human consumption (Chandrika and Rajagopalan 2007). Small-scale fisheries provide employment for millions of fishers directly engaged in fishing activities (including rural aquaculture). In addition, more than 100 million people are estimated to be employed in other fisheries-associated occupations (Ishak 1994; Vincent, Rozali, and Jahara 1997). These figures are likely to be underestimates, as there are millions of people fishing seasonally/part-time in coastal and inland waters not recorded as fishers. The Food and Agriculture Organization of the United Nations (FAO) estimates that about 5.8 million fishers (about 20% of the total) can be considered poor, earning less than US$1 per day. In addition, in many least developed countries of Africa and Asia, fish accounts for more than 50% of the total animal protein intake (FAO 1999). In almost all these countries, small-scale fisheries provide over three-quarters of the domestic fish supply. Small-scale fisheries are an important source of employment, food security, and income, particularly in the developing world. An estimated 90% of the 38 million people recorded by the FAO as fishers and fish farmers are small scale.

Economic Viability of Small-scale Marine Capture Fisheries in the Bonny Area, Rivers State, Nigeria

Economic Viability of Small-scale Marine Capture Fisheries in the Bonny Area, Rivers State, Nigeria

Arctic Fisheries Conservation and Management: Initial Steps of Reform of the International Legal Framework

Abstract The dramatic impacts that global climate change are expected to have in the future also extend to Arctic marine capture fisheries. Arctic marine ecosystems will change in various ways and this is among other things likely to create new or expanded fishing opportunities. This article assesses the adequacy of the current international legal and policy framework for Arctic fisheries conservation and management – both substantively and institutionally – in responding to the likely and potential impacts that such new or expanded fishing opportunities could have on target and nontarget species, the broader marine ecosystem and the livelihoods of indigenous peoples. The overview of the international legal and policy framework that is offered in this article is followed by the identification of gaps in this framework and in national regulation, and of options for addressing them. These options include increased efforts in the sphere of research and data gathering, bilateral fisheries management arrangements between Arctic Ocean coastal states, a declaration on new and existing fisheries in the Arctic Ocean and a state-of-the-art regional fisheries management organisation (RFMO) or Arrangement. Finally, some observations are made on integrated, cross-sectoral ecosystem-based oceans management.

Global overview on the use of fish meal and fish oil in industrially compounded aquafeeds: Trends and future prospects

The finfish and crustacean aquaculture sector is still highly dependent upon marine capture fisheries for sourcing key dietary nutrient inputs, including fish meal and fish oil. This dependency is particularly strong within compound aquafeeds for farmed carnivorous finfish species and marine shrimp. Results are presented concerning the responses received from a global survey conducted between December 2006 and October 2007 concerning the use of fish meal and fish oil within compound aquafeeds using a questionnaire sent to over 800 feed manufacturers, farmers, researchers, fishery specialists, and other stakeholders in over 50 countries. On the basis of the responses received, it is estimated that in 2006 the aquaculture sector consumed 3724 thousand tonnes of fish meal (68.2% total global fish meal production in 2006) and 835 thousand tonnes of fish oil (88.5% total reported fish oil production in 2006), or the equivalent of 16.6 million tonnes of small pelagic forage fish (using a wet fish to fish meal processing yield of 22.5% and wet fish to fish oil processing yield of 5%) with an overall fish-in fish-out ratio of 0.70. At a species-group level, calculation of small pelagic forage fish input per unit of farmed fish or crustacean output showed steadily decreasing fish-in fish-out ratios for all cultivated species from 1995 to 2006, with decreases being most dramatic for carnivorous fish species such as salmon (decreasing from 7.5 to 4.9 from 1995 to 2006), trout (decreasing from 6.0 to 3.4), eel (decreasing from 5.2 to 3.5), marine fish (decreasing from 3.0 to 2.2) and to a lesser extent shrimp (decreasing by 1.9 to 1.4 from 1995 to 2006. Net fish producing species in 2006 (with fish-in fish-out ratios below 1), included herbivorous and omnivorous finfish and crustacean species, including non-filter feeding Chinese carp (0.2), milkfish (0.2), tilapia (0.4), catfish (0.5), and freshwater crustaceans (0.6). On the basis of increasing global fish meal and fish oil costs, it is predicted that dietary fish meal and fish oil inclusion levels within compound aquafeeds will decrease in the long term, with fish meal and fish oil usage increasingly being targeted for use as a high value specialty feed ingredient for use within higher value starter, finisher and broodstock feeds, and by so doing extending supply of these much sought after and limited feed ingredient commodities.

Barriers to biodiversity conservation in marine fishery certification

AbstractTwo global certification and ecolabelling systems – the generic global dolphin‐safe ecolabel and the global Marine Stewardship Council (MSC) ecolabel – are assessed for their present and potential contributions to improving biodiversity conservation in marine capture fisheries. The dolphin‐safe ecolabel appears to have played a minor role in a reduction of dolphin mortality in tuna fisheries, but dolphin populations in the worst‐affected area have not recovered, and it appears that the current level of dolphin by‐catch sanctioned by present‐day fishery management and the ecolabel is not effective enough to achieve population recovery. The MSC ecolabel has established a poorly expressed environmental standard that has resulted in variable interpretations by certifiers, creating an apparently systematic bias in application of the standard to the certified fisheries. Without substantial revision of both these systems, it seems unlikely that they will be able to make major contributions to marine biodiversity conservation because of barriers created by limitations in programme design, lack of robust linkages between the certification standard and biodiversity conservation outcomes, and unclear standards and their inconsistent application in the certification of fisheries.

Supplementing Marine Capture Fisheries in the East China Sea: Sea Ranching of Prawn Penaeus orientalis, Restocking of Large Yellow Croaker Pseudosciaena crocea, and Cage Culture

The East China Sea is China's most productive fishing area. Maintaining harvest resulted in two notable sea ranching and restocking programs: the southward translocation of prawn (Penaeus orientalis) to establish a new fishery in Xiangshan Bay, and the release of large yellow croaker (Pseudosciaena crocea) to rebuild depleted populations. Penaeus orientalis were reared and released into Xiangshan Bay from 1986 to 1992. The new habitat supported all life stages, and stocked prawns provided a local put-and-take fishery. Although P. orientalis reproduced naturally, no lasting population was established because of the limited size of the releases and intense fishing pressure. From 2001 to 2006, 2–6 million juvenile P. crocea were released annually in Zhejiang Province, showing that it is feasible to release juvenile P. crocea and that they survive, feed, grow, spawn, and migrate, and are beginning to rebuild the population. Along with extensive fisheries, the East China Sea has thousands of hatcheries and some 1,000,000 aquaculture cages. To expand the industry while avoiding environmental problems associated with near-shore cages, large cages that can withstand storms are being used in deeper, well-flushed waters, resulting in improved product quality.

Maximum Sustainable Yield of Marine Capture Fisheries in Developing Archipelagic States—Balancing Law, Science, Politics and Practice

AbstractThe contemporary legal regime for marine capture fisheries is dominated by management based on maximum sustainable yield (MSY). This study examines the law, science, politics and practice of MSY in a selection of developing archipelagic states to assess whether and how MSY is being used in the management of single fish species and as part of a broader ecosystem approach to fisheries management.

Positioning fisheries in a changing world

Abstract 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.

Fishing capacity management in China: Theoretic and practical perspectives

Abstract The Food and Agriculture Organization (FAO) Committee on Fisheries (COFI) adopted an International Plan of Action for the Management of Fishing Capacity, which calls for all member states to achieve efficient, equitable and transparent management of fishing capacity by 2005. Based on the theoretical review of fishing capacity management, this paper examines the major practices made by China's government in managing the fishing capacity of its marine capture fisheries. Finally, it categorizes the main practices and then analyses and evaluates their effects.

Fishery Sector Development in Maharashtra: Issues, Strategies and Policy Implications

Although Maharashtra accounts for 14-20 per cent of the total marine fish production of India - which is almost stable over the past five years, the present fishing fleet of the state is not capable to exploit the deep sea resources. The state has formulated a scheme to introduce a medium size craft to exploit the resources in the depth of 70 fathoms with prolonged fishing cruise of 15 to 20 days in comparison to the present existing level of 4 to 10 days. This scheme so far has not given rich dividend. In fact, the major problem faced by the marine fisheries of Maharashtra is relating to depletion of resources due to illegal presence of foreign vessels and vessels belonging to other states, which appeared to have created pressure on the coast line. As a result, the marine fish production of Maharashtra has grown at very low pace during the last two decades. In order to tackle this problem, there is need for the Government of India to introduce zonalisation of coast line in the National Fishing Policy. This will not only help in stopping illegal presence other state's and foreign vessels but also in checking the depletion of resources. Some loop holes in the existing fishing laws should also be checked to prevent any illegal presence of vessels which deplete the marine resources. Notably, Maharashtra Fisheries Regulation Act (MHFRA) was introduced in the state in 1981. As per the provisions made in the Act, the mesh size of cord end of trawl net has been specified for different areas. And, these sizes are strictly followed. However, in order to maintain the existing marine fish stock there is need for the Government of India to implement uniform ban on illegal entry of other vessels in different coastal areas. It is to be further noted that the declining trends in inland water spread area, numerical strength of fish curing yards and stagnant number of fishery schools are certainly disturbing features of the fisheries sector of Maharashtra. However, in order to develop fisheries sector, the department of fisheries in the state is conducting various training programme relating to carp fish seed production, fresh water prawn culture, integrated fish farming and management of aquarium, etc. In order to develop fisheries sector in Maharashtra, there is need to educate fishermen with respect to dissemination of information relating to modern/mechanized fishing techniques and efficient marketing of fish catch. Equally important is the need for more innovative technologies in this sector, diffusion of developed technology by extension workers and adoption by the clients. Education of fishermen about modern fishing techniques is reported to have a significant impact on adoption of recommended fish culture practices by the farmers. It is also pointed out that extension and mass media participation have strong positive relationship with adoption of fish culture practices. Nonetheless, inadequate infrastructure and flow of information technology have been cited as the major barriers for better market integration in the existing marine fish markets of India. As for the overall development of fisheries sector of India, it is to be noted that since the target of fish production of 5.6 lakhs tons for 2003-04 was lower than the target of 6.3 lakhs tons for 2002-03, measures need to be taken to increase production of both marine and inland capture fisheries from reservoirs, etc. and culture fisheries to increase the overall fish production. There is also scope for exploitation of off-shore and deep sea fishery resources through introduction of newly designed fuel saving multi-day mechanized fishing vessels and deep sea fishing vessels. The need for the multi-day mechanized fishing vessels as well as the deep sea vessels is also felt in the state of Maharashtra.