Search

Aquatic foods from marine and freshwater systems are critical to the nutrition, health, livelihoods, economies and cultures of billions of people worldwide, but climate-related hazards may compromise their ability to provide these benefits. Here, we estimate national-level aquatic food system climate risk using an integrative food systems approach that connects climate hazards impacting marine and freshwater capture fisheries and aquaculture to their contributions to sustainable food system outcomes. We show that without mitigation, climate hazards pose high risks to nutritional, social, economic and environmental outcomes worldwide—especially for wild-capture fisheries in Africa, South and Southeast Asia, and Small Island Developing States. For countries projected to experience compound climate risks, reducing societal vulnerabilities can lower climate risk by margins similar to meeting Paris Agreement mitigation targets. System-level interventions addressing dimensions such as governance, gender equity and poverty are needed to enhance aquatic and terrestrial food system resilience and provide investments with large co-benefits towards meeting the Sustainable Development Goals. The nutritional, economic and livelihood contributions provided by aquatic food systems are threatened by climate change. Building climate resilience requires systemic interventions that reduce social vulnerabilities.

The future of the global ocean economy is currently envisioned as advancing towards a ‘blue economy’—socially equitable, environmentally sustainable and economically viable ocean industries1,2. However, tensions exist within sustainable development approaches, arising from differing perspectives framed around natural capital or social equity. Here we show that there are stark differences in outlook on the capacity for establishing a blue economy, and on its potential outcomes, when social conditions and governance capacity—not just resource availability—are considered, and we highlight limits to establishing multiple overlapping industries. This is reflected by an analysis using a fuzzy logic model to integrate indicators from multiple disciplines and to evaluate their current capacity to contribute to establishing equitable, sustainable and viable ocean sectors consistent with a blue economy approach. We find that the key differences in the capacity of regions to achieve a blue economy are not due to available natural resources, but include factors such as national stability, corruption and infrastructure, which can be improved through targeted investments and cross-scale cooperation. Knowledge gaps can be addressed by integrating historical natural and social science information on the drivers and outcomes of resource use and management, thus identifying equitable pathways to establishing or transforming ocean sectors1,3,4. Our results suggest that policymakers must engage researchers and stakeholders to promote evidence-based, collaborative planning that ensures that sectors are chosen carefully, that local benefits are prioritized, and that the blue economy delivers on its social, environmental and economic goals. The capacity to create an equitable and sustainable ‘blue economy’ from ocean resources will be determined by addressing social conditions, governance and infrastructure, not just resource availability, as shown by a fuzzy logic model incorporating multidisciplinary criteria.

Tropical fisheries substantially contribute to the well-being of societies in both the tropics and the extratropics, the latter through ‘telecoupling’ — linkages between distant human–natural systems. Tropical marine habitats and fish stocks, however, are vulnerable to the physical and biogeochemical oceanic changes associated with rising greenhouse gases. These changes to fish stocks, and subsequent impacts on fish production, have substantial implications for the UN Sustainable Development Goals. In this Review, we synthesize the effects of climate change on tropical marine fisheries, highlighting the socio-economic impacts to both tropical and extratropical nations, and discuss potential adaptation measures. Driven by ocean warming, acidification, deoxygenation and sea-level rise, the maximum catch potential of tropical fish stocks in some tropical exclusive economic zones is projected to decline by up to 40% by the 2050s under the RCP8.5 emissions scenario, relative to the 2000s. Climate-driven reductions in fisheries production and alterations in fish-species composition will subsequently increase the vulnerability of tropical countries with limited adaptive capacity. Thus, given the billions of people dependent on tropical marine fisheries in some capacity, there is a clear need to account for the effects of climate change on these resources and identify practical adaptations when building climate-resilient sustainable-development pathways. Stressors arising from anthropogenic climate change threaten tropical fisheries and, in turn, those extratropical nations reliant on them. This Review discusses the impact of climate change on tropical fish stocks and catch potential, the corresponding telecoupling and subsequent adaptation measures.

China is a key player in global production, consumption, and trade of seafood. Given this dominance, Chinese choices regarding what seafood to eat, and how and where to source it, are increasingly important—for China, and for the rest of the world. This perspective explores this issue using a transdisciplinary approach and discusses plausible trajectories and implications for assumptions of future modeling efforts and global environmental sustainability and seafood supply. We outline China's 2030 projected domestic seafood production and consumption through an examination of available statistics, and qualitatively evaluate these in relation to key stated Chinese policy targets, consumer trends, and dominant political narratives. Our analysis shows that by 2030 China is likely to see seafood consumption outstrip domestic production. To meet the seafood gap China will likely attempt to increase domestic freshwater and offshore aquaculture, increase seafood imports, possibly expand the distant water fishing industry, and invest in seafood production abroad.

Extreme temperature events have occurred in all ocean basins in the past two decades with detrimental impacts on marine biodiversity, ecosystem functions, and services. However, global impacts of temperature extremes on fish stocks, fisheries, and dependent people have not been quantified. Using an integrated climate-biodiversity-fisheries-economic impact model, we project that, on average, when an annual high temperature extreme occurs in an exclusive economic zone, 77% of exploited fishes and invertebrates therein will decrease in biomass while maximum catch potential will drop by 6%, adding to the decadal-scale mean impacts under climate change. The net negative impacts of high temperature extremes on fish stocks are projected to cause losses in fisheries revenues and livelihoods in most maritime countries, creating shocks to fisheries social-ecological systems particularly in climate-vulnerable areas. Our study highlights the need for rapid adaptation responses to extreme temperatures in addition to carbon mitigation to support sustainable ocean development.

Harmful fisheries subsidies contribute to overfishing leading to environmental and societal impacts1. If only fisheries within the subsidising nations’ jurisdiction were affected, then unilateral actions might be sufficient to help safeguard our ocean and the people reliant upon it. However, just as fish move between jurisdictions2, so too do the subsidised fishing fleets targeting them3. As such, the impacts and solutions to subsidies-induced overfishing are matters of international concern. Mapping that impact is therefore key to understanding these concerns and informing multilateral reform. Here we combine existing datasets4–6 to quantify the amount of harmful fisheries subsidies impacting the high seas, domestic and foreign waters, respectively. We estimate that between 24% and 43% of all harmful fisheries subsidies impact foreign waters or the high seas. We show that harmful subsidies primarily originate from countries with high-Human Development Index (HDI), strong fisheries management capacity and relatively sustainable fish stocks, yet disproportionately impact countries with low-HDI, lower management capacity and more vulnerable stocks. Indeed, over 40% of the harmful subsidies impacting low-HDI countries originate from high-HDI countries. This discrepancy between the source of harmful subsidies and the nations that are ultimately impacted is unsustainable and unjust. Policy-makers from all nations must push for effective multilateral subsidies reform. Prohibiting subsidies to distant-water fishing should be prioritised to support equitable and sustainable fisheries worldwide.

The objective of this study is to investigate the impacts of the environmental and socio-economic risks on the fisheries in the Mediterranean region from an economic point of view. A balanced panel of 21 Mediterranean countries for 2001–2018 has been estimated by the GLS method, considering heteroskedasticity and correlation among cross sections. The volume of fish landed and landed values have been considered in two models. The results show that increases in sea bottom and surface temperature, H+ ion concentration and salinity threaten the fisheries in the Mediterranean region for the volume of fish landed and that sea surface temperature and salinity negatively influence landed values. In addition, there is an inverse U-shaped relationship between human population and fisheries. Moreover, the Human Development Index (HDI), an indicator of countries’ adaptive capacity, has a positive impact on fisheries and indicates that countries can safeguard fisheries by improving their adaptive capacity. Finally, our results strongly show the risk of climate change for the fisheries in the Mediterranean region and that fisheries are adversely impacted by climate change as well as worsening socio-economic conditions in the absence of adaptation plans.

Following a brief review of their biology, this contribution is an attempt to provide a global overview of the catches of mesopelagic fishes (of which 2.68 million tonnes were officially reported to the FAO) throughout the world ocean from 1950 to 2018, to serve as a baseline to a future development of these fisheries. The overview is based on a thorough scanning of the literature dealing with commercial or experimental fisheries for mesopelagics and their catches, and/or the mesopelagic bycatch of other fisheries. All commercial (industrial and artisanal) fisheries for mesopelagic fishes were included, as well as experimental fisheries of which we were aware, while catches performed only to obtain scientific samples were omitted. The processes of generating bycatch and causing discards are discussed, with emphasis on Russian fisheries. From peer-reviewed and gray literature, we lifted information on mesopelagic fisheries and assembled it into one document, which we then summarized into two text tables with catch data, one by country/region, the other by species or species groups.

Thirteen Asian Large Marine Ecosystems (LMEs) ranging from the Arabian Sea LME in the West to the Western Bering Sea LME in the East are reported on in terms of their fisheries, catch trends and associated indicators such as the primary production required to maintain fishery catches, trends in the mean trophic levels of the catch, stock-status plots and others. Effective management of these LMEs is crucial for maintaining marine ecosystem system health and the goods and services the LMEs provide. Such management must be able to rely on credible catch data. The catch data used here were based on the national catch reconstructions performed by the Sea Around Us, as also documented in www.searoundus.org , but these could not fully compensate for the deficiencies of the fisheries statistical systems of several major countries in Asia, as reflected in exaggerated catch levels and uninformative catch compositions.

One of the aims of the United Nations (UN) negotiations on the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction (ABNJ) is to develop a legal process for the establishment of area-based management tools, including marine protected areas, in ABNJ. Here we use a conservation planning algorithm to integrate 55 global data layers on ABNJ species diversity, habitat heterogeneity, benthic features, productivity, and fishing as a means for highlighting priority regions in ABNJ to be considered for spatial protection. We also include information on forecasted species distributions under climate change. We found that parameterizing the planning algorithm to protect at least 30% of these key ABNJ conservation features, while avoiding areas of high fishing effort, yielded a solution that highlights 52,545,634 km2 (23.7%) of ABNJ as high priority regions for protection. Instructing the planning model to avoid ABNJ areas with high fishing effort resulted in relatively minor shifts in the planning solution, when compared to a separate model that did not consider fishing effort. Integrating information on climate change had a similarly minor influence on the planning solution, suggesting that climate-informed ABNJ protected areas may be able to protect biodiversity now and in the future. This globally standardized, data-driven process for identifying priority ABNJ regions for protection serves as a valuable complement to other expert-driven processes underway to highlight ecologically or biologically significant ABNJ regions. Both the outputs and methods exhibited in this analysis can additively inform UN decision-making concerning establishment of ABNJ protected areas.

Understanding conflicts between objectives of fisheries and conservation is the key to finding win-win situations for marine biodiversity and fishers. Many marine species are threatened by harmful interactions with fisheries, but the threats they face are associated with the fishing gear used. Here, we undertake a novel analysis of marine species and their gear-specific threats to evaluate conservation-fisheries trade-offs to identify areas with high competing goals. Our analysis suggests that gillnet and longline fisheries pose the greatest risk to marine species yet deliver relatively low profits, emphasizing the inefficiencies of these gears. We find that the majority of the high seas has low economic fisheries benefits with over 25% of the high seas categorized as areas of ‘conservation prioritisation’ over fisheries.

The future of the global ocean economy is currently envisioned as advancing towards a 'blue economy'-socially equitable, environmentally sustainable and economically viable ocean industries

The role that women play in fisheries around the world is receiving increasing international attention yet the contributions by women to fisheries catches continues to be overlooked by society, industry and policy makers. Here, we address this lack of visibility with a global estimation of small-scale fisheries catches by women. Our estimates reveal that women participate in small-scale fishing activities in all regions of the world, with approximately 2.1 million (± 86,000) women accounting for roughly 11% (± 4%) of participants in small-scale fishing activities, i.e., catching roughly 2.9 million (± 835,000) tonnes per year of marine fish and invertebrates. The landed value of the catch by women is estimated at USD 5.6 billion (± 1.5 billion), with an economic impact of USD 14.8 billion per year (± 4 billion), which is equivalent to 25.6 billion real 2010 dollars (± 7.2 billion). These catches are mostly taken along the shoreline, on foot, or from small, non-motorized vessels using low-technology, low-emission gears in coastal waters. Catches taken by women are often for home consumption, and thus considered part of the subsistence sub-sector. However, in many contexts, women also sell a portion of their catch, generating income for themselves and their families. These findings underscore the significant role of women as direct producers in small-scale fisheries value chains, making visible contributions by women to food and livelihood security, globally.

WOS:000579835900001; International audience; The global ocean is commonly partitioned into 4 biomes subdivided into 56 biogeochemical provinces (BGCPs) following the accepted partition proposed by Longhurst in 1998. Each province corresponds to a unique regional environment that shapes biodiversity and constrains ecosystem structure and functions. BGCPs are dynamic entities that change their spatial extent and position with climate and are expected to be pertubated in the near future by global climate change. Here, we characterize the changes in spatial distribution of BGCPs from 1950 to 2100 using three earth system models under two representative concentration pathways (RCP 2.6 and 8.5). We project a reorganisation of current distribution of BGCPs driven mostly by a poleward shift of their distributions (18.4 km in average per decade). Projection of the future distribution of BGCPs also revealed the emergence of new climate that has no analogue with past and current environmental conditions experienced by BGCPs . This novel environmental conditions, here named No-Analogue BGCPs State (NABS), will expand from 2040 to 2100 at a rate of 4.3 Mkm2 per decade (1.2% of the global ocean). We subsequently quantified the potential amount of marine species and fisheries catch that would experience such novel environmental conditions to roughly evaluate NABS impact on ecosystem services.

Fish are rich in bioavailable micronutrients, such as zinc and iron, deficiencies of which are a global food security concern.1,2 Global marine fisheries yields are threatened by climate change and overfishing,3,4 yet understanding of how these stressors affect the nutrients available from fisheries is lacking.5,6 Here, using global assessments of micronutrient content2 and fisheries catch data,7 we investigate how the vulnerability status of marine fish species8,9 may translate into vulnerability of micronutrient availability at scales of both individual species and entire fishery assemblages for 157 countries. We further quantify the micronutrient evenness of catches to identify countries where interventions can optimize micronutrient supply. Our global analysis, including >800 marine fish species, reveals that, at a species level, micronutrient availability and vulnerability to both climate change and overfishing varies greatly, with tropical species displaying a positive co-tolerance, indicating greater persistence to both stressors at a community level.10 Global fisheries catches had relatively low nutritional vulnerability to fishing. Catches with higher species richness tend to be nutrient dense and evenly distributed but are more vulnerable to climate change, with 40% of countries displaying high vulnerability. Countries with high prevalence of inadequate micronutrient intake tend to have the most nutrient-dense catches, but these same fisheries are highly vulnerable to climate change, with relatively lower capacity to adapt.11 Our analysis highlights the need to consolidate fisheries, climate, and food policies to secure the sustainable contribution of fish-derived micronutrients to food and nutrition security.

Knowing the patterns of marine resource exploitation and seafood trade may help countries to design their future strategic plans and development policies. To fully understand these patterns, it is necessary to identify where the benefits accumulate, how balanced the arrangements are, and how the pattern is evolving over time. Here the flow of global seafood was traced from locations of capture or production to their countries of consumption using novel approaches and databases. Results indicate an increasing dominance of Asian fleets by the volume of catch from the 1950s to the 2010s, including fishing in the high seas. The majority of landings were by high-income countries’ fishing fleets in their own waters in the 1950s but this pattern was greatly altered by the 2010s, with more equality in landings volume and value by fleets representing different income levels. Results also show that the higher the income of a country, the more valuable seafood it imports compared to its exports and vice versa. In theory, this implies that the lower income countries are exporting high value seafood in part to achieve the broader goal of ending poverty, while achieving the food security goal by retaining and importing lower value seafood. In the context of access arrangements between developed and developing countries, the results allow insights into the consequences of these shifting sources of income may have for goals such as poverty reduction and food security.

With the rapid growth of aquaculture, some negative factors of extensive monoculture accumulated, causing integrated multi-trophic aquaculture (IMTA) to draw increasing attention worldwide for its ecological and economic advantages. However, the development of IMTA in open water systems may not go as smoothly as anticipated—at least in Weihai, China, some producers who have adopted it would prefer to return to monoculture. This paper explores the problem from the angle of the economic performance by providing an in-depth analysis of costs and revenues generated by kelp monoculture and kelp-mollusk polyculture (IMTA). We find that the monoculture generates higher profits during the same production cycle. Besides inherent defects in system design, the rapidly growing labor cost and depressing selling price of the mollusk conspire to aggravate the economic failure of IMTA. Due to positive environmental externalities, the social benefits associated with IMTA are higher than the private benefits. This implies that there is a role for the government to generalize IMTA to achieve more total benefits. But single policy such as subsidies may backfire, a combination of policies designed to promote IMTA could be effective. Statement of relevance To study practical problems in aquaculture.

Coral reef preservation is a challenge for the whole of humanity, not just for the estimated three billion people that directly depend upon coral reefs for their livelihoods and food security. Ocean acidification combined with rising sea surface temperatures, and an array of other anthropogenic influences such as pollution, sedimentation, over fishing, and coral mining represent the key threats currently facing coral reef survival. Here we summarize a list of agreements, policies, and socioeconomic tools and instruments that can be used by global, national and local decision-makers to address ocean acidification and associated threats, as identified during an expert workshop in October 2017. We then discuss these tools and instruments at a global level and identify the key tasks for raising decision makers' awareness. Finally, we suggest ways of prioritizing between different actions or tools for mitigation and adaptation. (c) 2019 Published by Elsevier B.V.

The Paris Agreement is good for fish, fishers, seafood workers, and consumers., The Paris Agreement aims to mitigate the potential impacts of climate change on ecological and social systems. Using an ensemble of climate-marine ecosystem and economic models, we explore the effects of implementing the Agreement on fish, fishers, and seafood consumers worldwide. We find that implementing the Agreement could protect millions of metric tons in annual worldwide catch of top revenue-generating fish species, as well as billions of dollars annually of fishers’ revenues, seafood workers’ income, and household seafood expenditure. Further, our analysis predicts that 75% of maritime countries would benefit from this protection, and that ~90% of this protected catch would occur within the territorial waters of developing countries. Thus, implementing the Paris Agreement could prove to be crucial for the future of the world’s ocean ecosystems and economies.

Previous studies assessing climate change impacts on marine fisheries focus on the impacts from changing ocean conditions on fish distribution, catch, and related human well-being. However, these studies often neglect the effects of changing productivity of living marine resources, fisheries management measures, and the economics of fishing on fishers’ behavior and fishing effort. In return, the fishers’ decisions and the dynamics of fishing effort would impact the abundance of fisheries resources. Also the projected impacts on the economies through fisheries have different implications for different countries. Thus, this chapter highlights the importance of projecting and applying plausible fishing and economic scenarios in understanding climate change impacts on fisheries and discusses the importance of projecting fishing effort dynamics. Results from the studies on the economics of fishing and fishing effort dynamics under climate change have great implications on the design of fisheries management plans for adapting to climate change.

Climate change is impacting marine ecosystems and their goods and services in diverse ways, which can directly hinder our ability to achieve the Sustainable Development Goals (SDGs), set out under the 2030 Agenda for Sustainable Development. Through expert elicitation and a literature review, we find that most climate change effects have a wide variety of negative consequences across marine ecosystem services, though most studies have highlighted impacts from warming and consequences of marine species. Climate change is expected to negatively influence marine ecosystem services through global stressors—such as ocean warming and acidification—but also by amplifying local and regional stressors such as freshwater runoff and pollution load. Experts indicated that all SDGs would be overwhelmingly negatively affected by these climate impacts on marine ecosystem services, with eliminating hunger being among the most directly negatively affected SDG. Despite these challenges, the SDGs aiming to transform our consumption and production practices and develop clean energy systems are found to be least affected by marine climate impacts. These findings represent a strategic point of entry for countries to achieve sustainable development, given that these two goals are relatively robust to climate impacts and that they are important pre‐requisite for other SDGs. Our results suggest that climate change impacts on marine ecosystems are set to make the SDGs a moving target travelling away from us. Effective and urgent action towards sustainable development, including mitigating and adapting to climate impacts on marine systems are important to achieve the SDGs, but the longer this action stalls the more distant these goals will become.

The impacts of banning wild spat collection are crucial for the future development of the Zhikong scallop fishery. Failure to the quantitative analysis of economic impacts obstructs the understanding of policy performance. Using key parameters extracted from the data and information through field research, we estimate the financial losses in spat collection, mariculture, and processing sectors. Our results show that the local ban should spark a chain reaction on the national Zhikong scallop fishery and potentially cause substantial economic consequences. The decreasing profitability and growing negative externalities of traditional mariculture are the main reasons for the local government to overhaul its marine development strategy. These findings have implications for some problems in the current marine management system or, from a more positive perspective, the crisis of the Zhikong scallop fishery providing China an opportunity to accelerate reforms for sustainable mariculture.

Climate change affects ocean conditions, fish stocks and hence fisheries. In West Africa, climate change impacts on fisheries were projected to be mainly negative through multi-facet ways. However, analysis of adaptation responses of fishers to climate change impacts is scarce. This paper reviews the impacts on climate change on fisheries in West Africa and discusses the potential adaptation strategies adopted by both the artisanal and industrial fishing sectors. Overall, climate change and over-exploitation have altered species composition of fisheries catches in West Africa. The effect of ocean warming on fisheries is indicated by the increase in dominance of warmer water species in the landings, shown from an increase in Mean Temperature of Catch, in the region. Climate change induced changes in potential catch and species composition, which inherently have similar symptoms as over-exploitation, are expected to have repercussions on the economic and social performance of fisheries. Both artisanal and industrial sectors may adapt to these changes mainly through expansion of fishing ground that increases operation costs. Our results highlight that historical changes in target species are more common in industrial than artisanal fisheries. This result challenges the prevailing assumption that artisanal fisheries, given their limited movement capacity, would adapt to climate change by shifting target species and/or gear type.

Climate change is projected to redistribute fisheries resources, resulting in tropical regions suffering decreases in seafood production. While sustainably managing marine ecosystems contributes to building climate resilience, these solutions require transformation of ocean governance. Recent studies and international initiatives suggest that conserving high seas biodiversity and fish stocks will have ecological and economic benefits; however, implications for seafood security under climate change have not been examined. Here, we apply global-scale mechanistic species distribution models to 30 major straddling fish stocks to show that transforming high seas fisheries governance could increase resilience to climate change impacts. By closing the high seas to fishing or cooperatively managing its fisheries, we project that catches in exclusive economic zones (EEZs) would likely increase by around 10% by 2050 relative to 2000 under climate change (representative concentration pathway 4.5 and 8.5), compensating for the expected losses (around −6%) from ‘business-as-usual’. Specifically, high seas closure increases the resilience of fish stocks, as indicated by a mean species abundance index, by 30% in EEZs. We suggest that improving high seas fisheries governance would increase the resilience of coastal countries to climate change.

In 2005, the Sea Around Us described a website (www.seaaroundus.org) which presented, for all maritime countries and large marine ecosystems in the world, one of the most basic information items required by policy makers and fisheries managers: what catch was taken within their jurisdictional boundaries, and which countries took it. Surprisingly, for many countries this kind of jurisdictionally and/or ecologically assigned data had not been readily available before then. Since the release of these spatialized data, this material has had major influence on how fisheries are perceived by policy makers in various countries and by the global scientific community, as well as by a growing list of other stakeholders such as non-governmental environmental organizations and the general public. Here, the Sea Around Us updates the fisheries science, policy, conservation and management audience on the extensively modified spatial allocation method and a substantially improved new website. Also, this contribution points to and describes the much improved catch data underlying this website. These data now account for catches for all countries in the world by fisheries sectors (industrial, artisanal, subsistence, recreational), after augmenting the officially reported landings data through the inclusion of comprehensively reconstructed data of previously unreported catches and major discards, for every maritime country or territory in the world, and their Exclusive Economic Zone (EEZ). Also presented are the extensively improved spatial allocation procedures which assign global catch data to the 180,000 half degree spatial cells used by the Sea Around Us to subdivide the global ocean. The reconstructed data for 1950–2010 for all countries in the world and the High Seas, freely accessible and downloadable through the Sea Around Us web portal, will be updated regularly. It is hoped that these revised data and the substantially improved web utility will invigorate and assist the debate about the role of fisheries in a global framework as well as in national food security settings.

The aim of this paper is to provide an updated estimate of global fisheries subsidies. It builds on earlier estimates and methodologies to re-estimate and discuss the various types of subsidies provided by governments around the world. The results suggests that total subsidies were about USD 35 billion in 2009 dollars, which is close to the earlier estimate of 2003 subsidies once they are adjusted for inflation. Capacity-enhancing subsidies constituted the highest category at over USD 20 billion. For all regions, the amount of capacity-enhancing subsidies is higher than other categories, except for North America, which has higher beneficial subsidies. The analysis reveals that fuel subsidies constitute the greatest part of the total subsidy (22% of the total), followed by subsidies for management (20% of the total) and ports and harbors (10% of the total). Subsidies provided by developed countries are far greater (65% of the total) than those by developing countries (35% of the total) even though the latter lands well above 50% of total global catch. Asia is by far the greatest subsidizing region (43% of total), followed by Europe (25% of total) and North America (16% of total). Japan provides the highest amount of subsidies (19.7% of total), followed by the United States and China at 19.6% of total.

The global ocean is projected to be warmer, less oxygenated and more acidic in the 21st century relative to the present day, resulting in changes in the biogeography and productivity of marine organisms and ecosystems. Previous studies using a Dynamic Bioclimate Envelope Model (DBEM) projected increases in potential catch in high latitude regions and decreases in tropical regions over the next few decades. A major structural uncertainty of the projected redistribution of species and fisheries catches can be attributed to the habitat suitability algorithms used. Here, we compare the DBEM projections of potential catches of 500 species of exploited marine fishes and invertebrates from 1971 to 2060 using three versions of DBEM that differ by the algorithm used to predict relative habitat suitability: DBEM-Basic, DBEM-Maxent and DBEM-Aquamaps. All the DBEM models have similar skill in predicting the occurrence of exploited species and distribution of observed fisheries production. Globally, the models project a decrease in catch potential of 3% to 13% by 2050 under a high emissions scenario (Representative Concentration Pathway 8.5). For the majority of the modelled species, projections by DBEM-Maxent are less sensitive to changes in ocean properties than those by DBEM-Aquamaps. The mean magnitude of projected changes relative to differences between projections differ between regions, being highest (>1 times the standard deviation) in the tropical regions and Arctic Ocean and lowest in three of the main Eastern Boundary Upwelling regions, the eastern Indian Ocean and the Southern Ocean. These results suggest that the qualitative patterns of changes in catch potential reported in previous studies are not affected by the structural uncertainty of DBEM, particularly in areas where catch potential was projected to be most sensitive to climate change. However, when making projections of fish stocks and their potential catches using DBEM in the future, multiple versions of DBEM should be used to quantify the uncertainty associated with structural uncertainty of the models. Overall, this study contributes to improving projection of future changes in living marine resources by exploring one aspect of the cascade of uncertainty associated with such projections.

The effects of climate change on the ocean environment – especially ocean warming, acidification, and sea level rise – will impact fish stocks and fishers in important ways. Likely impacts include changes in fish stocks’ productivity and distribution, human migration to and away from coastal areas, stresses on coastal fisheries infrastructure, and challenges to prevailing maritime boundaries. In this paper, we explore these and other related phenomena, in order to assess whether and how the impacts of climate change on fisheries will contribute to the risk of fisheries conflict. We argue that climate change will entail an increase in the conditions that may precipitate fisheries conflict, and thereby create new challenges for existing fisheries management institutions. Several potential changes in fisheries management policy are recommended to avert the growing risk of fisheries-related conflicts.

Climate change–reflected in significant environmental changes such as warming, sea level rise, shifts in salinity, oxygen and other ocean conditions–is expected to impact marine organisms and associated fisheries. This study provides an assessment of the potential impacts on, and the vulnerability of, marine biodiversity and fisheries catches in the Arabian Gulf under climate change. To this end, using three separate niche modelling approaches under a ‘business-as-usual’ climate change scenario, we projected the future habitat suitability of the Arabian Gulf (also known as the Persian Gulf) for 55 expert-identified priority species, including charismatic and non-fish species. Second, we conducted a vulnerability assessment of national economies to climate change impacts on fisheries. The modelling outputs suggested a high rate of local extinction (up to 35% of initial species richness) by 2090 relative to 2010. Spatially, projected local extinctions are highest in the southwestern part of the Gulf, off the coast of Saudi Arabia, Qatar and the United Arab Emirates (UAE). While the projected patterns provided useful indicators of potential climate change impacts on the region’s diversity, the magnitude of changes in habitat suitability are more uncertain. Fisheries-specific results suggested reduced future catch potential for several countries on the western side of the Gulf, with projections differing only slightly among models. Qatar and the UAE were particularly affected, with more than a 26% drop in future fish catch potential. Integrating changes in catch potential with socio-economic indicators suggested the fisheries of Bahrain and Iran may be most vulnerable to climate change. We discuss limitations of the indicators and the methods used, as well as the implications of our overall findings for conservation and fisheries management policies in the region.

We present the first joint analysis of the ecological−financial deficits of nations and develop a simple index, the Eco2 index, which is useful in ranking the combined ecological and financial performance of countries. This index includes information on ecological and financial deficits, trade surplus and gross domestic product (GDP) to evaluate the potential impacts of ecological deficits on the overall economic performance of countries. Results show an ongoing trend towards increased ecological deficits, as natural resources are ‘traded’ for financial gain. We argue that countries cannot run large financial deficits forever without negative economic consequences and that globally, it is likewise impossible to ignore our global ecological deficit in the long run. Ecological deficits can only be temporarily and partially addressed by incurring financial costs through imports, bounded by available resource surpluses of other nations and the fact that some of these services are place-specific. Ultimately, ecological deficits jeopardize ecosystem functions, energy sources and the food security of nations, with direct implications for human well-being.

The job of fisheries scientists is to provide evidence that can be used for fisheries management both in tactical terms (i.e., from one year to the next) and strategically, in term of their broad orientations. Catch reconstructions, which consider all fisheries in a given area, can help with the latter, but they are often contested, as broad assumptions must often be made to reconcile and harmonize divergent data sets. Here, contra Chaboud et al. (Comment on “Fisheries catch misreporting and its implications: The case of Senegal”) on Belhabib et al., 2013 , Belhabib et al., 2014b , we justify the assumptions and methods we used, in close collaboration with Senegalese government agencies, to reconstruct the historic and current artisanal catch of Senegal and the illegal catch taken by foreign industrial vessels in Senegalese waters. This done, we argue that such work, rather than haggling about the number of pirogues deployed decades ago, is a current task of fisheries scientists working on Senegalese fisheries, and by extension, elsewhere in West Africa, where the conflict between artisanal and foreign industrial fisheries is most acute.

Photosynthesis fuels marine food webs, yet differences in fish catch across globally distributed marine ecosystems far exceed differences in net primary production (NPP). We consider the hypothesis that ecosystem-level variations in pelagic and benthic energy flows from phytoplankton to fish, trophic transfer efficiencies, and fishing effort can quantitatively reconcile this contrast in an energetically consistent manner. To test this hypothesis, we enlist global fish catch data that include previously neglected contributions from small-scale fisheries, a synthesis of global fishing effort, and plankton food web energy flux estimates from a prototype high-resolution global earth system model (ESM). After removing a small number of lightly fished ecosystems, stark interregional differences in fish catch per unit area can be explained (r = 0.79) with an energy-based model that (i) considers dynamic interregional differences in benthic and pelagic energy pathways connecting phytoplankton and fish, (ii) depresses trophic transfer efficiencies in the tropics and, less critically, (iii) associates elevated trophic transfer efficiencies with benthic-predominant systems. Model catch estimates are generally within a factor of 2 of values spanning two orders of magnitude. Climate change projections show that the same macroecological patterns explaining dramatic regional catch differences in the contemporary ocean amplify catch trends, producing changes that may exceed 50% in some regions by the end of the 21st century under high-emissions scenarios. Models failing to resolve these trophodynamic patterns may significantly underestimate regional fisheries catch trends and hinder adaptation to climate change.

Ghana has a long fishing tradition, including industrial fishing. After many of the countries where Ghanaian fleets were actively fishing declared an Exclusive Economic Zone in the 1980s, the distant-water fleet of Ghana returned to its home waters, precipitating a collapse of some local stocks. While official catches reported to the FAO document this decline, the catches of other sectors (artisanal, subsistence, and recreational fishing) were not reported, their contribution to the livelihoods of Ghanaians was simply not documented, and their impact on fish stocks overlooked. Herein, total catches were estimated at 20.8 million tonnes between 1950 and 2010 compared to 11.8 million tonnes reported to the FAO. Subsistence catches, notably from coastal lagoons represented the bulk of unreported catches and seemed to have increased overall during this period, while the artisanal and large-scale sector catches decreased. Furthermore, the economic contribution of artisanal fisheries to Ghana is declining mainl...

The marine resources in Senegal are still relatively abundant, and Senegalese fisheries generate a high economic value for local communities. These fisheries are characterized by a large number of distant-water fleets alternating between legal and illegal operations, depending on circumstances, and a rapid increase of artisanal fishing effort. The extent of the impact of artisanal fisheries on fisheries resources and the Senegalese economy is as poorly known as is the level of illegal unreported and unregulated (IUU) industrial fishing. The former relies on official surveys and voluntary reports by fishers, while the existence of the latter was largely denied in the past. Large and frequent ‘migrations’ (i.e., incursions into the waters of neighbouring countries) by Senegalese artisanal fishers, under-estimation of fishing effort and increasing conflicts over fisheries suggest that officially reported catch data do not reflect reality. A thorough literature review, experts and industry consultations were used to reconstruct Senegalese fisheries catch data. Official national data were compared to the data supplied to FAO and adjusted from 1950 to 2010. Reported and missing sub-sectors, including artisanal catches within and outside Senegalese waters, non-commercial sub-sectors, and industrial catches by the legal and illegal fleets, were conservatively re-assessed. The impacts of the intensive illegal fishing activities on artisanal fisheries and the economy were investigated. The results showed substantial under-reporting, ranging from 4 times higher than the official data in the past to about 1.6 times recently. Artisanal fisheries, according to official data, were responsible for 50% of total extractions, as opposed to 80% 20 years ago. However, while catches by migrant fishers increased dramatically, artisanal catches from Senegalese waters decreased despite an increasing effort, suggesting over-capacity. IUU catches, which were worth around $ 300 million US annually, whether transhipped or otherwise spirited out of Senegalese waters, or discarded, represent a huge loss to Senegal. Also, the foreign fleet, illegally exploiting Senegalese fisheries resources, impact strongly on the migrations of Senegalese artisanal fishers, who in turn increase their migrations as an adaptation strategy to meet their need for fish in the face of rapid resource depletion.

Shallow coral reefs provide food, income, well-being and coastal protection to countries around the Indian Ocean and Asia. These reefs are under threat due to many anthropogenic stressors including pollution, sedimentation, overfishing, sea surface warming and habitat destruction. Ocean acidification interacts with these factors to exacerbate stress on coral reefs. Effective solutions in tackling the impact of ocean acidification require a thorough understanding of the current adaptive capacity of each nation to deal with the consequences. Here, we aim to help the decision-making process for policy makers in dealing with these future challenges at the regional and national levels. We recommend that a series of evaluations be made to understand the current status of each nation in this region in dealing with ocean acidification impacts by assessing the climate policy, education, policy coherence, related research activities, adaptive capacity of reef-dependent economic sectors and local management. Indonesia and Thailand, are selected as case studies. We also highlight general recommendations on mitigation and adaptation to ocean acidification impacts on coral reefs and propose well-designed research program would be necessary for developing a more targeted policy agenda in this region.

We conservatively estimate the distant-water fleet catch of the People’s Republic of China for 2000–2011, using a newly assembled database of reported occurrence of Chinese fishing vessels in various parts of the world and information on the annual catch by vessel type. Given the unreliability of official statistics, uncertainty of results was estimated through a regionally stratified Monte Carlo approach, which documents the presence and number of Chinese vessels in Exclusive Economic Zones and then multiplies these by the expected annual catch per vessel. We find that China, which over-reports its domestic catch, substantially under-reports the catch of its distant-water fleets. This catch, estimated at 4.6 million t year 1 (95% central distribution, 3.4–6.1 million t year 1 ) from 2000 to 2011 (compared with an average of 368 000 tyear 1 reported by China to FAO), corresponds to an exvessel landed value of 8.93 billion € year 1 (95% central distribution, 6.3– 12.3 billion). Chinese distant-water fleets extract the largest catch in African waters (3.1 million t year 1 , 95% central distribution, 2.0–4.4 million t), followed by Asia (1.0 million t year 1 , 0.56–1.5 million t), Oceania (198 000 t year 1 , 144 000–262 000 t), Central and South America (182 000 t year 1 , 94 000– 299 000 t) and Antarctica (48 000 t year 1 , 8 000–129 000 t). The uncertainty

Previous studies highlight the winners and losers in fisheries under climate change based on shifts in biomass, species composition and potential catches. Understanding how climate change is likely to alter the fisheries revenues of maritime countries is a crucial next step towards the development of effective socio-economic policy and food sustainability strategies to mitigate and adapt to climate change. Particularly, fish prices and cross-oceans connections through distant water fishing operations may largely modify the projected climate change impacts on fisheries revenues. However, these factors have not formally been considered in global studies. Here, using climate-living marine resources simulation models, we show that global fisheries revenues could drop by 35% more than the projected decrease in catches by the 2050 s under high CO2 emission scenarios. Regionally, the projected increases in fish catch in high latitudes may not translate into increases in revenues because of the increasing dominance of low value fish, and the decrease in catches by these countries’ vessels operating in more severely impacted distant waters. Also, we find that developing countries with high fisheries dependency are negatively impacted. Our results suggest the need to conduct full-fledged economic analyses of the potential economic effects of climate change on global marine fisheries.

We investigate how high seas closure will affect the availability of commonly consumed food fish in 46 fish reliant, and/or low income countries. Domestic consumption of straddling fish species (fish that would be affected by high seas closure) occurred in 54% of the assessed countries. The majority (70%) of countries were projected to experience net catch gains following high seas closure. However, countries with projected catch gains and that also consumed the straddling fish species domestically made up only 37% of the assessed countries. In contrast, much fewer countries (25%) were projected to incur net losses from high seas closure, and of these, straddling species were used domestically in less than half (45%) of the countries. Our findings suggest that, given the current consumption patterns of straddling species, high seas closure may only directly benefit the supply of domestically consumed food fish in a small number of fish reliant and/or low income countries. In particular, it may not have a substantial impact on improving domestic fish supply in countries with the greatest need for improved access to affordable fish, as only one third of this group used straddling fish species domestically. Also, food security in countries with projected net catch gains but where straddling fish species are not consumed domestically may still benefit indirectly via economic activities arising from the increased availability of non-domestically consumed straddling fish species following high seas closure. Consequently, this study suggests that high seas closure can potentially improve marine resource sustainability as well as contribute to human well-being in some of the poorest and most fish dependent countries worldwide. However, caution is required because high seas closure may also negatively affect fish availability in countries that are already impoverished and fish insecure.

In the ocean, biological responses to climate change include altered distribution, phenology and productivity. A modelling study into the integrated effects of these various changes on fish body size suggests that averaged maximum body weight could fall by 14–24% globally by 2050. About half of the decline is accounted for by changes in distribution and abundance, with the remainder being physiological.

Marine oil spills usually harm organisms at two interfaces: near the water surface and on shore. However, because of the depth of the April 2010 Deepwater Horizon well blowout, deeper parts of the Gulf of Mexico are likely impacted. We estimate the potential negative economic effects of this blowout and oil spill on commercial and recreational fishing, as well as mariculture (marine aquaculture) in the US Gulf area, by computing potential losses throughout the fish value chain. We find that the spill could, in the next 7 years, result in (midpoint) present value losses of total revenues, total profits, wages, and economic impact of US$3.7, US$1.9, US$1.2, and US$8.7 billion, respectively. Commercial and recreational fisheries would likely suffer the most losses, with a respective estimated US$1.6 and US$1.9 billion of total revenue losses, US$0.8 and US$1.1 billion in total profit losses, and US$4.9 and US$3.5 billion of total economic losses.