Multifunctionality is characterized by two key elements: the existence of jointly produced multiple commodity and non-commodity outputs (NCOs), and that NCOs exhibit the characteristics of public goods externalities. The term “multifunctionality” is almost not used outside agriculture. However, several issues discussed in fishery literature and in international contexts clearly refer to public goods provision and joint production. The key point is to recognize if fisheries, similar to agriculture, provide other (public) benefits beyond their primary food supply function. The paper establishes a theoretical framework for the classification and valuation of multifunctionality in fisheries, and outlines policy options to increase (through multifunctionality) social welfare. NCOs include: ecosystem- and biodiversity-related NCOs, other environmental public goods/bads, cultural heritage and coastal viability, coastal employment externalities, food security, and strategic benefits. The main NCO characteristics to be analysed are the degree of jointness between commodity outputs and NCOs, and the distribution of property rights over fish stocks and NCOs. Policy options to increase social welfare include, among others, command and control schemes, market based instruments (e.g., payment for ecosystem services), and marine protected areas. Customary marine tenure institutions, or other modern fishery organizations, may represent a framework for the communitarian provision of NCOs. Fishery subsidies, which can because of overfishing, are justified if they allow increasing social benefits, given by the sum of catch and NCOs value. Particularly, incentives may be necessary to support small-scale fisheries or other less efficient technologies.
Aquaculture, Seafood, and Food Security
We assess the vulnerability to climate change of Korean aquaculture based on predicted changes in seawater temperature and salinity in adjacent sea areas of the Korean Peninsula according to representative concentration pathways (RCP) scenarios. Unlike previous studies that have been conducted mostly on a national scale, we classify 14 farming species in major production regions of the Republic of Korea, and assess their vulnerability for each region, using the indicator-based method and the Intergovernmental Panel on Climate Change's definition of vulnerability in order to overcome limitations in developing specific adaptation strategies within a country. First, for each exposure, sensitivity, and adaptive capacity, specific and proper indicators are selected. Subsequently, these indicators are estimated and weighted to analyze vulnerability to climate change. The results show that the absolute level of vulnerability is high in a long-term period of RCP8.5 in which exposure becomes severe, whereas the relative vulnerability is similar among farming species and regions. Specifically, vulnerability is at the highest level in seaweed, such as laver and sea mustard, while fish, shrimp, and abalone are relatively less vulnerable to climate change.
Carrying capacity models for aquaculture have increased in complexity over the last decades, partly because aquaculture growth, sustainability, and licensing are themselves extremely complex. Moreover, there is an asymmetric pattern to all these components, when considered from an international perspective, because of very different regulation and governance of the aquaculture sector in Asia, Europe, and America. Two case studies were used, from Long Island Sound in the United States, and Belfast Lough, in Europe, to examine the interactions between cultivated shellfish and other autochthonous benthic filter-feeders. The objective is to illustrate how such interactions can be incorporated in system-scale ecological models and analyzed from the perspective of ecological carrying capacity. Two different models are described, one based on equations that relate the filtration rate of the hard clam Mercenaria mercenaria to physiological and population factors and one based on a habitat-specific analysis of multiple species of benthic filter-feeders. Both types of models have relative advantages and challenges, and both were integrated in ecosystem modeling frameworks with substantial numbers of state variables representing physical and biogeochemical processes. These models were applied to (1) examine the relative role of the two components (cultivated and wild) in the filtration of particulate organic matter (both phytoplankton and organic detritus), (2) quantify the effect of wild species on harvest of cultivated organisms (eastern oyster and blue mussel), and (3) assess the role of organically extractive aquaculture and other filter-feeders on top–down control of eutrophication.
Key environmental challenges faced by the aquaculture sector demonstrate that aquaculture production is not isolated from the surrounding environment, and we see a policy shift towards area‐based approaches. However, without an understanding of the farmer's perspective, there is a danger of misrepresenting how farm‐level practices relate to area‐based approaches and to environmental risk management. This paper empirically examines how individual aquaculture farmers interpret and manage environmental risks and the extent to which they operate beyond the boundaries of their farms. The analysis is based on a comparison between intensive aquaculture farmers in Kung Krabaen Bay, Thailand, representing an area of closed production systems; and a mixture of integrated mangrove shrimp and extensive shrimp farmers in Kien Vang Forest, Vietnam, representing an area of open production systems. Data were collected through semi‐structured interviews and participatory mapping. The spatial configuration of environmental risk management in both areas demonstrated a focus on the farm. Though farmers did recognise off‐farm risks, this did not result in collectively practised risk management strategies at a broad landscape scale. These observations demonstrate the need to rethink the development of area‐based approaches for both closed and open systems. Instead of the designation of aquaculture zones or all‐encompassing integrated landscape models of area‐based management, the findings suggest an alternative model. This third way of conceptualising spatial models of area‐based aquaculture management is based on a nested set of areas within a landscape defined by the socio‐spatial extent of farmer networks within which the interpretation of risk is homogeneous.
Aquaculture is a booming industry. It currently supplies almost half of all fish and shellfish eaten today, and it continues to grow faster than any other food production sector. But it is immature relative to terrestrial crop and livestock sectors, and as a consequence it lags behind in terms of the use of aquaculture specific financial risk management tools. In particular, the use of insurance instruments to manage weather related losses is little used. In the aquaculture industry there is a need for new insurance products that achieve both financial gains, in terms of reduced production and revenue risk, and environmental wins, in terms of incentivizing improved management practices. Here, we have developed a cooperative form of indemnity insurance for application to small-holder aquaculture communities in developing nations. We use and advance the theory of risk pools, applying it to an aquaculture community in Myanmar, using empirical data recently collected from a comprehensive farm survey. These data were used to parameterize numerical simulations of this aquaculture system with and without a risk pool. Results highlight the benefits and costs of a risk pool, for various combinations of key parameters. This information reveals a path forward for creating new risk management products for aquaculturalists around the world.
Climate change is an immediate and future threat to food security globally. The consequences for fisheries and agriculture production potential are well studied, yet the possible outcomes for aquaculture (that is, aquatic farming)—one of the fastest growing food sectors on the planet—remain a major gap in scientific understanding. With over one-third of aquaculture produced in marine waters and this proportion increasing, it is critical to anticipate new opportunities and challenges in marine production under climate change. Here, we model and map the effect of warming ocean conditions (Representative Concentration Pathway scenario 8.5) on marine aquaculture production potential over the next century, based on thermal tolerance and growth data of 180 cultured finfish and bivalve species. We find heterogeneous patterns of gains and losses, but an overall greater probability of declines worldwide. Accounting for multiple drivers of species growth, including shifts in temperature, chlorophyll and ocean acidification, reveals potentially greater declines in bivalve aquaculture compared with finfish production. This study addresses a missing component in food security research and sustainable development planning by identifying regions that will face potentially greater climate change challenges and resilience with regards to marine aquaculture in the coming decades. Understanding the scale and magnitude of future increases and reductions in aquaculture potential is critical for designing effective and efficient use and protection of the oceans, and ultimately for feeding the planet sustainably.
Compliance with a policy, law, standard or code requires understanding of its provisions. However, for someone to understand it, he must be aware of its existence and be provided access to it. A qualitative-quantitative research was conducted to determine the awareness of milkfish farmers about the Philippine Code of Practice for Aquaculture in the municipalities of Leganes and Zarraga, Iloilo Province, the Philippines and their information-seeking behaviors. Results revealed that the majority of the respondents were not aware of the existence of the Code, hence, there is a low level of compliance. When seeking everyday life information, the majority of the milkfish farmers depended on television, personal or person-to-person communication and radio, while when seeking for fish farming information, personal communication was the preferred source. None of the respondents was aware of the existence of their municipal libraries.
The aquaculture sector is anticipated to be a keystone in food production systems in the coming decades. However, it is associated with potentially important environmental damages caused by its contribution to eutrophication or climate change, for example. To comprehensively quantify those impacts, life cycle assessment (LCA) studies have been conducted on several seafood farming systems for the past 15 years. But, what major findings and common trends can we draw from this pool of studies? What can we learn to provide recommendations to decision and policymakers in the aquaculture sector? To address these questions, we performed a critical review of 65 LCA studies of aquaculture systems from the open literature. We conducted quantitative analyses to explore which impacts can be identified as dominating and to compare different types of aquaculture systems. Our results evidenced that the feed production is a key driver for climate change, acidification, cumulative energy use and net primary production use, while the farming process is a key driver for eutrophication. We also found that different aquaculture systems and technology components may exert considerably different environmental impacts. Based on identified patterns and comparisons, we therefore provided specific recommendations to aquaculture stakeholders for future policy and system development. Overall, the analysis of existing studies demonstrates that important insights can be gained by applying LCA to aquaculture systems, and, to move towards an environmentally sustainable aquaculture sector, we recommend its systematic use in the design of new aquaculture systems or policies, and/or in the evaluation and optimization of existing ones.
The marine, intertidal zone is the optimal environment for eelgrass (Zostera spp.) and bivalve aquaculture. Eelgrass is a valuable and protected nearshore habitat. It is important to understand how bivalve aquaculture interacts with eelgrass to support the sustainable development of this globally expanding industry. This study provides a comprehensive understanding of the positive and negative effects of bivalve aquaculture on eelgrass by conducting the first quantitative, global meta-analysis of aquaculture-eelgrass studies. A literature review resulted in 125 studies that met established criteria for inclusion in this analysis. The meta-analysis determined: (1) how eelgrass responds to on-bottom and off-bottom bivalve aquaculture, (2) how these responses vary between regions and specific grow-out methods, and (3) the resilience of eelgrass after harvesting disturbances. On-bottom culture (laying directly on the sediment potentially including predator exclusion devices) corresponded to significant increases in eelgrass growth and reproduction, and a decrease in density and biomass. Off-bottom culture (e.g., longline and suspended bag) resulted in significant decreases in eelgrass density, percent cover, and reproduction. Results support a space-competition hypothesis for on-bottom culture and provide limited support for light limitation in off-bottom culture, although other mechanisms of interaction are potentially occurring as well. A US west coast case study revealed regional differences in eelgrass responses, including a more negative trend in eelgrass density from off-bottom culture, and a neutral effect on reproduction from on-bottom culture (relative to neutral and positive trend, respectively, in the average of all other studies). Eelgrass densities recovered after all harvest methods, however mechanical harvest methods created greater initial impact and longer recovery times than manual harvest methods. The time-period over which observations were reported was an important variable that was not included in the analysis but could influence these results. These analyses suggest the response of eelgrass to bivalve aquaculture varies depending on eelgrass characteristics, grow-out approaches, and harvesting methods, with potential regionally specific relationships. Questions remain, regarding how this dynamic relationship between eelgrass and aquaculture habitat relate to ecological functions and services in the nearshore environment.
Recent international negotiations have highlighted the need to protect marine diversity on the high seas—the ocean area beyond national jurisdiction. However, restricting fishing access on the high seas raises many concerns, including how such restrictions would affect food security. We analyze high seas catches and trade data to determine the contribution of the high seas catch to global seafood production, the main species caught on the high seas, and the primary markets where these species are sold. By volume, the total catch from the high seas accounts for 4.2% of annual marine capture fisheries production and 2.4% of total seafood production, including freshwater fisheries and aquaculture. Thirty-nine fish and invertebrate species account for 99.5% of the high seas targeted catch, but only one species, Antarctic toothfish, is caught exclusively on the high seas. The remaining catch, which is caught both on the high seas and in national jurisdictions, is made up primarily of tunas, billfishes, small pelagic fishes, pelagic squids, toothfish, and krill. Most high seas species are destined for upscale food and supplement markets in developed, food-secure countries, such as Japan, the European Union, and the United States, suggesting that, in aggregate, high seas fisheries play a negligible role in ensuring global food security.