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Climate Smart Agriculture Sourcebook

Climate-Smart fisheries and aquaculture

Production and Resources

Climate-smart fisheries and aquaculture

Climate-smart approaches in fisheries and aquaculture address three key objectives. The first objective is connected to the overarching goal of achieving sustainable food systems, and encompasses the environmental, social and economic aspects of fisheries, including both commercial fleets and artisanal fisheries, and aquaculture. The second objective focuses on the need to reduce the vulnerability of the sector to the impacts of climate change and build the sector's resilience so that it can cope with the impacts climate variability and climate change are projected to have on the availability of resources, and with natural disasters caused by an increased incidence of severe weather episodes. The third objective is to enable the sector, where possible, to contribute to the mitigation of greenhouse gases emissions during the harvest and production stages and throughout the entire value chain, which, given the high level of processing, transport and marketing activities involved in the sector, is extremely important. 

Climate-smart approaches in this sector are connected with most, if not all, of the major cross-cutting themes of sustainable development. As in other sectors, several issues need to be recognized and reconciled for climate-smart approaches to become the default pathway for development. Existing practices, such as ecosystem-based management, fall within climate-smart approaches (see Box B4.2 and Annex 1). 

Key considerations include the need to:

Expand the evidence base:

Available data on observed and projected climate change impacts have become more detailed for the individual chemical and physical drivers of change, especially in the oceans. However, the combined effects of all the drivers are still limited. More detailed knowledge on the regional and subregional impacts of climate change is required to understand the vulnerabilities of individual ecosystems, capture fisheries, aquaculture systems, food processing and trade, and the communities and societies that are directly or indirectly dependent on them. Expanding the evidence base regarding the levels of exposure, vulnerabilities and risks will allow for the formulation of well-targeted adaptation strategies. Further research on the sector's potential to mitigate climate change by reducing emissions and/or improving carbon storage would also support climate-smart development. Given the growing global demand for fisheries products and the importance of fish products for the survival of the most impoverished, understanding how to align adaptation and mitigation strategies and at the same time increase production in an environmentally responsible manner is key for sectoral development and global food security. 

Support enabling frameworks:

In many countries, fisheries and aquaculture play an important role in supporting livelihoods and safeguarding food and nutrition security. To maintain or improve these contributions, well-structured, enabling policy frameworks and investment plans need to be developed and implemented. These frameworks and plans should not address fisheries and aquaculture in isolation, but consider how the National policy-makers should have sufficient capacities to be able to engage with local government authorities and participate in international fora on climate change and fisheries and aquaculture. Strong institutions that are well embedded within the political landscape, are better positioned to identify and address specific gaps in capacity, efficiency and system resilience for the sector, particularly those gaps that are likely to increase under climate change, and identify generic or specific actions to address these gaps. Strong local institutions that can empower, enable and motivate small-scale fishers and fish farmers are essential, as they provide opportunities for the reciprocal exchange of knowledge (traditional and modern), capacity needs and future plans. 

Enhance financing options:

Innovative mechanisms that link and blend climate finance and investments to sector-specific needs are essential for developing and implementing climate-smart fisheries and aquaculture. The Green Climate Fund, which promotes low-emission and climate-resilient development pathways, is one of the key international financing instruments for the sustainable agricultural development, including the fisheries and aquaculture sector. Strong and all-encompassing Nationally Appropriate Mitigation Actions and National Adaptation Plans are important policy instruments for creating links to domestic and international financing. National budgets and official development assistance will continue to be main sources of funding. Integrating climate concerns into sectoral planning and budgeting is a prerequisite for successfully addressing climate change at national and subnational levels.

Implement practices in the field: 

Small-scale fishers and fish farmers are the primary sources of knowledge about their environment, aquatic ecosystems, fish and other aquatic species and local climatic patterns. Adopting climate-smart fisheries and aquaculture should be closely linked to local fishers and farmers’ knowledge, requirements and priorities. Suitable climate-smart strategies can be identified through the participation of fishers and farmers in local projects. Climate-smart approaches must be recognizable and actionable by policy agents in order to work effectively with practitioners and beneficiaries at all levels. Capacity building for non-governmental stakeholders improves their ability to support sustainable national and subnational policies. In addition, in some developing countries, support for local associations, in some cases leading to fisheries or farm cluster certification, has been brought about through interactions in field with industry and/or the government. More interventions in the field with all stakeholders involved would improve the development of good practices and speed the uptake of field-tested climate-smart adaptation measures by local communities that are most vulnerable to climate change. 

Fisheries and aquaculture have distinct characteristics, including:

  • specific issues of ecosystem complexity, with multiple-scale interactions of seascapes, watersheds and landscapes, uncertainties of change and impacts, and the difficulty of developing robust and practical models that are accessible to users;
  • the particularly rapid interactions of pollutants and pathogens in aquatic environments, which are being affected by various drivers of acidification and climate change, and creating potential risks to productivity, stocks and human health; 
  • data scarcity and difficulties in obtaining data in complex, highly heterogeneous, social, economic and ecological systems, and the challenge of creating a common understanding of important issues across these different systems and stakeholders.
  • the significant level of social and economic dependence on wild fish stocks in small- and large-scale ecosystems, which are associated with a wide range of activities that are driving climate change;
  • social issues related to the ‘last-resort’ or emergency uses of fisheries resources, and the widespread social marginalization and poverty in fishing communities along many of the supply chains; 
  • very limited development of risk and insurance markets for both capture fisheries and aquaculture, and few mechanisms for community-based responses to less stable conditions; 
  • the continued challenge of governance issues, particularly for fisheries resources, including the substantial levels of IUU fishing, and widespread fleet overcapacity;
  • the transboundary nature of major resource systems, including areas beyond national jurisdiction, and the political complexity of resource management systems;
  • the high concentration of aquaculture in the tropics and very populated areas;
  • the significant contribution to food security and nutrition made by small-scale fisheries, which make affordable fish available and accessible to poor populations and are a key means for sustaining livelihoods in marginalized and vulnerable populations, compared to large-scale industrial fishing (HLPE, 2014).

In such a complex environment, fully causal and quantitative relationships between climate variability, climate change and its impacts on fisheries and aquaculture cannot realistically be established. 

However, much can be done to reduce vulnerability using practical approaches. There is considerable knowledge on how to build and maintain the resilience of natural ecosystems and the human communities that inhabit them. In the fisheries and aquaculture sector, there is no lack of guidance in this area. The FAO Code of Conduct for Responsible Fisheriesiii articulates the principles and standards applicable to the conservation, management and development of the world’s fisheries, including aquaculture (FAO, 1995). These principles and standards cover a range of issues, including the prevention of overfishing; the minimization of negative impacts of fisheries and aquaculture to aquatic ecosystems and local communities; and the protection of human rights for a secure and just livelihood. The Voluntary Guidelines for Securing Sustainable Small-Scale Fisheries in the Context of Food Security and Poverty Eradicationiv (FAO, 2015b) provide complementary guidance to the Code of Conduct with respect to small-scale fisheries. The Voluntary Guidelines call on all parties to recognize and take into account the impact of natural disasters and climate change on small-scale fisheries and recommend that appropriate adaptation, mitigation and aid plans be taken, in line with human rights principles. The ecosystem approach to fisheries and aquaculture provides the strategies and tools for implementing the Code of Conduct and the Voluntary Guidelines and proposes a holistic, integrated and participatory approach for the sustainable management of fisheries and aquaculture systems under all conditions, including under climate change and climate variability. The direct benefits of implementing the ecosystem approach are outlined in Box B4.2. 

Detailed information on the ecosystem approach to fisheries and aquaculture can be found in Annex 1. Improving the general resilience of fisheries and aquaculture systems can reduce their vulnerability to the impacts of climate change and climate variability on resources and to severe weather episodes that trigger natural disasters. Systems rich in biodiversity are less sensitive to change than overfished systems with little diversity. For example, healthy coral reef and mangrove systems, which provide habitat to a wealth of biodiversity, provide many benefits, including acting as natural barriers to physical impacts of climate change. In addition, healthy, sustainably managed mangrove systems and seaweed farms have high capacities for sequestering and storing carbon. Well managed mangroves and seaweed farms also provide the ideal habitat for many fish species’ reproduction and feed requirements and contribute to the sustainable supply of fish. Improved resilience, including encouraging the consumption of a greater diversity of fish species, utilizing by-products from processing and reducing waste along the value chain, can contribute to stabilizing the availability of nutritious food and securing income for communities that are directly or indirectly dependent on capture fisheries and aquaculture for their livelihoods. Safeguarding a stable supply of fish and fisheries products can enable the development of stronger social systems and create livelihood options from within the communities that rely on fisheries and aquaculture.

Box B4.2 Direct benefits of implementing the ecosystem approach to fisheries and aquaculture include:

  • Supporting resilient ecosystems, communities and governance structures and reducing the exposure of the sector to risks, by increasing the aquatic systems’ potential to absorb and recover from change, making communities engaged in fishing and aquaculture less sensitive to change, and increasing the sector’s adaptive capacity;
  • Improving the efficient use of natural and human resources for food and livelihood security;
  • Supporting intersectoral collaboration, particularly the integration of climate change adaptation and disaster risk management in fisheries and aquaculture strategies, and integrated resource management (e.g. integrated coastal zone or watershed management and water planning);
  • Promoting integrated monitoring and information systems that incorporate scientific and local knowledge;
  • Improving general awareness and knowledge of climate change inside and outside the sector;
  • Promoting context-specific and community-based adaptation strategies;
  • Avoiding 'maladaptation' (e.g. overly rigid fishing access regimes that inhibit fisher migrations and adaptation actions that increase fishing in an overfished fishery);
  • Embracing adaptive management, decision-making under uncertainty and the precautionary approach; 
  • Promoting natural barriers and defences against variability and change, and natural disasters rather than hard barriers that affect the ecosystem; and
  • Unlocking financial potential.

B4 - 4.1 Sustainably increasing productivity and efficiency and addressing constraints to market access

There are two principal approaches for increasing productivity and efficiency in aquatic systems. For capture fisheries, the essential issues are: reducing excess capacity and ensuring the fishing effort is following improved fisheries management; and maintaining healthy and productive stocks and systems. Although total fishery production might not be increased to any significant extent, there is room to reduce costs, particularly fuel costs. A reduction in fuel costs, most likely brought about by a reduction in the amount of fuel used, would improve economic efficiency and reduce greenhouse gas emissions. Better stock conditions may also improve the quality of the catch. Performance could be enhanced by adopting improved handling practice that reduce losses during harvesting (e.g. the icing of fish or the use of drying ovens when refrigeration is not available) and lowering the amount of bycatch and/or improving its utilization. Finally, by reducing waste along the fish value chain, which is estimated to be approximately 30 percent of total production, the amount of fish needed to meet nutritional needs could be reduced, which would reduce the pressure on overutilized fisheries. 

For aquaculture, the primary emphasis is on sustainably intensifying production, using more fully integrated systems, improving productivity of farmed strains, making feeding more efficient and reducing losses from disease (De Silva and Soto, 2009; Troell et al., 2014a). All of this must be accomplished without compromising the nutritional quality and safety of the product (Beveridge et al., 2013). Dependence on fishmeal and fish oil is often cited as a primary constraint to growth for aquaculture (Hasan and Halwart, 2009; Hall et al., 2011; Little et al. 2016). Although this dependence is slowly declining, as alternative feeds are being developed, fishmeal and fish oil are still used as feed ingredients (Tacon and Metian, 2008; Hasan and Halwart, 2009). In both inland and coastal areas, it is also increasingly likely that aquaculture development will face constraints related to the availability of land and water resources (Troell et al., 2014b). These constraints are a consequence of increased competition from other sectors and changing agro-ecological conditions. In some cases, aquaculture production systems may need to be relocated (FAO and World Bank, 2015). Within the aquaculture subsector, aquaponics presents a potential option for increasing efficiency in ways that address existing constraints (see Box B4.3 for an overview on aquaponics). 

In food processing and other activities that add value to fisheries and aquaculture products, efforts should be made to reduce losses and waste, and produce more product in less time. Increasing the efficiency of product storage and distribution also deserves attention. 

The overarching principles of sustainable fisheries and aquaculture are found in the FAO Code of Conduct for Responsible Fisheries and related guidelines. These principles provide guidance on the approaches to follow to achieve sustainable increases in productivity and efficiency. The principles may be progressively elaborated upon with more specific guidance as more experience is gained in climate-smart policies and practices. Tools and best practices for improving efficiency and sustainability that cover the social, economic and ecological aspects of fisheries and aquaculture are under development and being tailored to accommodate climate change and climate variability. However, one of the key constraints in developing effective advice on adaptive management is the often limited data and information on which to base concrete decisions.

Box B4.3 An Overview on Aquaponics - Integrating Aquaculture and Hydroponics

Aquaponics is a symbiotic integration of two mature food production systems: aquaculture, the practice of fish farming, and hydroponics, the cultivation of plants in water without soil. The two production systems are combined within a closed recirculating system. In a standard recirculating aquaculture system, the organic matter ('waste') that builds up in the water needs to be filtered and removed to keep the water clean for the fish. In an aquaponic system, the nutrient‐rich effluent is filtered through an inert substrate containing the rooting system of plants. Here, bacteria metabolize the fish waste, and plants assimilate the resulting nutrients. The purified water is then returned to the fish tanks. 

Aquaponics is one type of integrated agriculture/aquaculture technique that meets the criteria of climate-smart agriculture. It sustainably increases food security by increasing agricultural productivity and incomes. Producing value-added products (both fish and vegetables), aquaponics also contributes to reducing watershed pollution, which often originates from fertilizer runoff and aquaculture effluent discharge. It has the potential to deliver higher yields of produce and protein with less labour and land, fewer chemicals and a fraction of the water usage. At the same time, aquaponics is a resilient system that can be adapted to diverse and changing conditions. Being a strictly controlled system, it combines a high level of biosecurity with a low risk of disease and external contamination, while producing high yields without the need for fertilizers and pesticides. Moreover, it is a potentially useful tool to overcome some of the challenges traditional agriculture is facing, such as shortages fresh water, climate change and soil degradation. Aquaponics works well where the soil is poor and water is scarce, for example in urban areas, arid climates and low-lying islands. Although research is scant, aquaponics produces relatively fewer greenhouse gas emissions to produce the same amount of product. This is because of the high efficiency of feed, the reduction of mineral fertilizer, and the lower energy expenditure as there is no need to till, plough or work the soil. The highly efficeint use of space means that less farm land is required to grow the same amount of food.

However, commercial aquaponics is not appropriate in all locations, and many aquaponic businesses have not been successful. Large-scale systems require careful consideration before financial investment, especially regarding the availability and affordability of inputs (i.e. fish feed, building and plumbing supplies), the cost and reliability of electricity, and access to a significant market willing to pay premium prices for local, pesticide-free vegetables. Aquaponics combines the risks of both aquaculture and hydroponics, and expert assessment and consultation is essential. As a relatively new technique, aquaponics is subject to ongoing research around the world from both knowledge institutions and entrepreneurs, who are looking at ways to develop economies of scale, reduce capital expenditure, and make the systems and technology simpler and more available to small- and medium-scale farmers. 

FAO has started work supporting aquaponic development and has published a technical manual on the subject, Small-scale Aquaponic Food Production (FAO, 2014). During the Thirty-first Session of the FAO Committee on Fisheries, aquaponics was raised by four Member Countries (Cook Islands, Indonesia, Kenya, and Mexico) as a subject that deserves increased attention. A side event at the session included a presentation by the Indonesian delegation on Yumina, a form of aquaponics used in homesteads across the country. As a follow-up, Indonesia, with support from FAO and the South-South Cooperation team, conducted a regional aquaponic technical training workshop in Indonesia in 2015 to train trainers from other countries in the region. Separately, FAO convened an aquaponic training workshop for countries in the Near East and North Africa. FAO has previously supported aquaponic development in Antigua, and will conduct regional training and build demonstration sites in other Caribbean countries. 

Aquaponics has the potential to support economic development and enhance food security and nutrition by fostering an efficient and integrated use of resources, and will become another option for addressing the challenge of charting a sustainable path to global food and nutrition security 

FAO, 2016a

B4 - 4.2 Reducing vulnerability and increasing resilience

Reducing vulnerability

The risks that climate change presents to the fisheries and aquaculture sector are similar to those in other agriculture sectors. However, there are risks that are specifically related to aquatic environments and the open access nature of fisheries that are not shared, or shared to a much lesser degree, by terrestrial systems. Relative to terrestrial food production systems, significantly less research has been conducted on the risks to the fisheries and aquaculture sector. There remain many unanswered questions about the ultimate impacts of climate change on fish resources, especially at regional and local levels. However, the impacts that have been identified are generally negative for the tropics and SIDS. In northern latitudes, the impacts could provide potential gains to fisheries. 

It should be noted that changing conditions may bring development opportunities to tropical multispecies fisheries, as they may improve ecosystem functions and increase productivity. Rising sea levels could also create more opportunities for brackish water aquaculture. Practical actions to reduce vulnerability and increase resilience have typically focused on addressing the uncertainties and risks related to livelihoods and production systems, which are exacerbated by climate variability and increasingly severe weather episodes. 

Decisions as to which options to select will depend on a number of factors: the location and scale of change and the attendant risk to the dependent communities; the impacts and the perception of their effects; and the cost, complexity and time required to implement countermeasures. To increase the overall resilience of a system, priority may be given to small and inexpensive changes in practices that can quickly reduce the risks for the most vulnerable. Box B4.4 provides an overview of ways to improve resilience with moderate levels of resources in culture-based fisheries.

When a system's exposure to climate change becomes severe, and adaptive capacity is limited, small and inexpensive actions may not be enough to increase the system’s resilience. Implementing small and inexpensive, but insufficient actions, could provide a false sense of security (e.g. in the case of extreme events) when the long-term impacts are projected to become more and more severe. Faced with increasing severity, a long-term strategic approach may be needed that may involve, for example, the development of new technologies, improvements in the accessibility of finance, or changes in livelihoods for communities at risk. 

Premature overinvestment in expensive forms of protection may dangerous, in that they may deprive communities of important financial resources and protect only some sectors of the population. Protecting and strengthening one area, community or activity can result in a trade-off that leaves others relatively unprotected, and these potential trade-offs should be considered in policy decisions. Over longer periods, infrastructure development and the relocation of people towards safer or less vulnerable areas may be the solution. Early investments oriented toward short-term solutions may serve merely to delay the inevitable.

Marine and inland fisheries and aquaculture farms are likely to continue to be affected by climate change, climate variability and extreme events in a number of ways, including: reduced yields, changes in the variety of fish species, the nutrients available for coastal fisheries and aquaculture farms, sea level rise, and shifts in production due to rising temperatures, acidification and pathogens. Annex 2 provides a non-exclusive list on impact areas and potential responses for reducing vulnerability in fisheries and aquaculture. Given that specific fisheries and aquaculture systems will be affected differently by the impacts of climate change, Annex 2.2 outlines possible response options to these impacts in a range of fisheries systems. Figure 1 in Annex 2.3 presents the impacts and response options in specific aquaculture systems. The impacts and response options in specific post-harvest (processing, marketing and trade) systems are outlined in Annex 2.4

The response options provided in Annex 2.1 – 2.4 take into consideration the potential level of severity of change. The levels of disturbance are categorized as: minor disruptions, which are relatively easy to accommodate through normal patterns of operations, but may merit some adjustments to reduce risks and impacts; significant disruptions, which are sufficient in frequency and magnitude to require adjustments outside the normal patterns of operations, but usually only require modifications to already familiar patterns; and major disruptions whose frequency and/or magnitude expose the system to unsupportable levels of risk, making it imperative to undertake modifications, some but not all of which could be based on existing systems. 

In the broader response to uncertain vectors of change, approaches that incorporates climate-smart disaster risk reduction and disaster risk management are also of value. These approaches originated in post-disaster interventions (e.g. storms, floods, tsunamis) where there was the need to measure and reduce similar risks to vulnerable communities. However, they can be applied more proactively and used to anticipate and respond to the complete profile of climate change impacts in a given context. These approaches can be improve the connections to response needs in areas where storms are also associated with sea level surges, salinization of ground water, and/or the destruction of nursery habitats.

Often interactions with other sectors that are also affected by climate change must be considered. For example, inland fisheries are particularly sensitive to policies and actions outside the sector, as fresh water resources have many other uses and are often exposed to pollutants. Similarly, many coastal environments are increasingly subject to changes in freshwater runoff, agricultural intensification, growth in the industrial and energy sector, expanded urbanization and transport, and the development of tourism. For aquaculture, there are also interactions and trade-offs with other sectors, particularly regarding land and water use, aquatic and terrestrially derived feeds, and the negotiation of coastal space. Defining and valuing the role and needs of the fisheries and aquaculture sector, raising awareness about the sector and designing policies to address climate change and other aspects of development that can deliver cross-sectoral benefits are key challenges.

Box B4.4 Options for culture based fisheries to improve climate resilience 

Culture-based fisheries is typically a perennial and seasonal stock enhancement process. It is practiced in smaller water bodies and even flooded fields, which under normal conditions would not support a significant fishery through natural recruitment. In culture-based fisheries, the stocked fish are managed communally with ownership rights. It therefore falls within the realm of aquaculture. Recently, the practice has gained momentum due to the increasing demand for fish and improvements in seed stock production and availability. Culture-based fisheries has also become a major part of government strategies to increase fish production for food and improve livelihoods, particularly in impoverished rural communities (Amarasinghe and Nguyen, 2009). 

Culture-based fisheries as an environmentally friendly food production system

In many instances, culture-based fisheries is seen as a practice with a small environmental footprint and a good example of multiple, effective use of water resources (De Silva, 2003). Culture-based fisheries does not consume water or external feed resources. The only input is the seed stock. The stocked species are selected in a manner that fills vacant food niches and ensures that natural food production can maintain the growth and well-being of the stock. Consequently, the yields are similar to wild capture fisheries but less than in most intensive aquaculture practices. However, culture-based fisheries is environmentally friendly, the costs are minimal and there are no emissions related to feed. This semi-intensive to extensive form of aquaculture often utilizes communal water bodies. For governments in developing countries, the practice is an attractive means for increasing fish production and food security in rural communities.

The possibilities of stocked fish mingling with wild counterparts are higher than in normal aquaculture practices. For this reason, whenever possible, indigenous fish species are recommended for culture-based fisheries in purposely constructed, artificial water bodies. The stocking or enhancement of open waters is far more complex and raises a range of issue relating to the mixing of farmed and wild stocks, genetic introgression and disease. The hatchery bred stocks that are introduced should originate from well managed broodstock. Ideally, the broodstock would originate from wild stocks and be as close as possible to the wild type. In all cases, risk assessment is recommended before stocking to ensure that potential downstream impacts on the wild stocks and the environment are identified and mitigated.

Culture-based fisheries sensitivity to climate change and adaptation potential

As in all primary production activities, culture-based fisheries cycles are subject to the elements, primarily rainfall patterns, which entails a certain degree of unpredictability in the water levels. This is beyond human control. The available mitigating measures will involve careful planning to accomodate the hydrological cycle of the waterbodies. This might involve, for example, making adjustments in stocking and harvesting. Risks are associated with the greater frequency of flash floods, changes in monsoonal rain patterns and longer periods of dry weather, all of which are attributed to climate change and can have an impact the productivity of the system. In seasonal or perennial waters bodies, stocking is best done when the water body is filling up or full, and harvesting often takes place when the water level recedes. In areas where a large number of water bodies are used for culture-based fisheries, there may be a seasonal glut of fish at harvest, which can affect prices. Ideally, organizing marketing activities so that sales are staggered can help stabilize prices. Culture-based fisheries fits within an ecosystem management perspective and can be a sustainable and successful food production strategy, if appropriate precautions and strategies are in place. This requires both coordination within the fishery sector and with water management authorities to ensure that water bodies are not drained unexpectedly. 

Increasing resilience

It has been observed that marine and inland fisheries and aquaculture resources and those dependent on them are likely to continue to be affected by climate change. Depending on the region, these affects can either be positive or negative. Response strategies for different fisheries and aquaculture systems, taking into account the severity of (potential) impacts are outlined in Annex 2. These strategies aim to preserve the natural environment and related ecosystem services that communities and societies directly and indirectly  depend on. When designing and implementing these strategies, several key principles to base analysis and action should be included:

  • Systems with more diversity tend to have greater resilience.
  • Initiatives to build resilience can connect across scales. Actions to build resilience at the local-level can reinforce each other to create greater resilience on a broader scale. National resilience, which can be improved, for example, through market and economic strategies, can create a more positive environment for building local resilience.
  • Perspectives for resilience need to acknowledge all the elements in the impact pathway for development.
  • Trade-offs between the risk to resilience and costs of building resilience should be identified.
  • Climate change-induced drivers can be important, but they may not be the only factors that need to be addressed.
  • If vulnerability is addressed only selectively or partially, remaining vulnerabilities may jeopardize or even negate any positive effects.
  • People with resilient livelihoods are better able to withstand damage, recover and adapt to change. 
  • Unresolved issues outside the fisheries and aquaculture sector may limit the potential for building resilience. The analysis for identifying best adaptation and disaster risk reduction strategies should therefore understand the fisheries and aquaculture sector in a wider setting (e.g. the socio-economic situation, the status of other environmental resources, policies outside the sector that entail implications for its sustainability). 

B4 - 4.3 Reducing and removing greenhouse gases

Greenhouse gas emissions from fisheries and aquaculture are associated with various aspects of production and distribution. The management of the aquatic ecosystem has important potential for reducing net greenhouse gas emissions through the natural sequestration of carbon. One possible mitigation option is aquatic biofuel production, which could be linked with fisheries and aquaculture production. There are also potential connections with mitigation efforts in the energy sector in areas such as hydropower and coastal and offshore renewable energy. The next section address three areas: the sector’s own contribution to greenhouse gas emissions and the potential for reducing these emissions; the sector’s potential role in supporting the natural system’s removal of emissions; and the sector’s role in providing alternative energy sources.

The role of fisheries and aquaculture in reducing emissions

Information on greenhouse gas emissions from aquatic food production and distribution systems and the potential to reduce them is becoming more clearly understood (Hall et al., 2011; Poseidon, 2012; Muir, 2012; Waite et al., 2014). For capture fisheries emissions are primarily related to fuel use. The nature of these emissions and their levels depend on technical aspects, such as types of vessels and gear used (e.g. active/passive gear, trawl, dredge, seine, gillnet, longline, light-attraction fishing, traps) (Muir, 2013). Emissions are also determined by market forces and the management of fishing capacity. For example, when too many vessels chase after fewer and fewer fish fuel use tends to increase. Emissions of particulate ‘black’ carbon could significantly add to current estimates, but this issue needs further investigation. For aquaculture, feed is considered to be the primary determining factor for emission levels, with fertilizers being a secondary factor (FAO, 2016c). Emissions tend to increase as aquaculture production progresses from an extensive system, in which there is no treatment and/or only partial fertilization, to semi-intensive systems which use fertilizers and/or partial feeding, to intensive systems, in which the stock is completely nourished on feed. Fuel and energy used to exchange and treat the water, and power service vessels, vehicles, and equipment also generate carbon dioxide emissions, but usually at much less significant levels. The effects of methane and nitrous oxide in sediments and the water column, which are relatively undetermined, are also potentially important and require further study.

The processing of fish and aquatic animals ranges from simple artisanal drying and smoking to tightly controlled seafood preparation using high-specification packaging and labelling. In the processing stages, energy use is the primary determining factor for greenhouse gas emissions. There are wide variations in emissions depending on local practices, input variations (e.g species, sourcing, quantity and quality) and operating efficiency. Water used in food processing may also be an important factor in determining greenhouse gas emissions. Aquatic foods may travel considerable distances in a range of forms and in various states of perishability. During transport, greenhouse gas outputs are usually directly related to fuel and energy use in handling and cold and freezer storage. The specific choice of refrigerants is also important. Leakage from old or poorly maintained equipment can be critical, as many low ozone-depleting gases have significant global warming potential. The most perishable fresh products require transport methods (e.g. local trucks, live fish vessels and air transport) that emit relatively high levels of greenhouse gas. Cooled and frozen product that require less time-critical transport methods (e.g. ship-borne reefer and freezer containers) generate fewer emissions. More stable products (dried, smoked and salted products), particularly those processed in artisanal supply chains, require methods for transport that are not time-sensitive and produce the lowest levels of emissions.

The ratios of greenhouse gas emissions per tonne of fish and aquatic foods at the production, distribution and retail stages are similar to those for other foods. Emissions at first sale account for typically 25-40 percent of total outputs. However, these figures vary widely. Limited numbers of comparative assessments of carbon dioxide equivalents per kilogram (kg) across the different food production systems suggest that fisheries operations that use high amounts of fuel (e.g. poorly catching trawl or dredge fisheries) combined with energy-intensive post-harvest processing can be among the most greenhouse gas-intensive food systems. Passive fishing gear systems or lower trophic level aquaculture (e.g. bivalves, seaweeds) can produce as much foods as most systems of meat or animal protein production, but release far fewer emissions. The expansion of these systems has the potential to contribute to strategic shifts in consumption patterns and reduce global greenhouse gas emissions. 

Box B4.5 provides an overview on a comparative analysis conducted by Hilborn and Tellier (2012) on the energy efficiency of fisheries production systems. 

Box B4.5 The environmental costs of New Zealand food production

In New Zealand, fisheries had a lower impact in terms of water and fertilizer use, eutrophication  potential and antibiotics when compared with dairy and meat production. Most fisheries also had lower levels of greenhouse gas emission than the meat industry, and some were lower than those for average dairy production. The dairy and meat industries were more efficient in energy inputs and production per unit, but the healthy state of major fish stocks ensured relatively efficient fuel consumption scores. The New Zealand quota management system also discouraged excessive vessel capacity and largely eliminated competitive open access fishing, which reduced fuel consumption. Compared to other countries, the New Zealand dairy and meat industries were more efficient in energy use and greenhouse gas emissions. The authors attribute this relative efficiency to high year-round productivity, and the ability to raise both dairy animals and other livestock on pasture for most of the year, which reduces the need to use feed crops.

Environmental indicators per 40 g protein portion in New Zealand food production systems 

Inputs

Outputs

Energy

FreshWater

Fertilizer

Pesticides

Antibiotics

Surface Area Impacted

Greenhouse gases

Eutrophicatin potential*

Acidification potential**

Megajoules

   (litres)

   (g)

    (kg)

     (mg)

     (m2)

  (kg CO2)

        (g)

      (g)

NZ Dairy

1.56

171

26

24

1.17

1.24

0.86

3

8.4

NZ Meat

4.9

262

188

129

1.17

18.14

3.7

13.3

36.8

NZ Squid

7.11

0

0

n/a

0

17

0.62

1.7

3.9

NZ Hoki

7.11

0

0

n/a

0

100

0.64

1.7

4

NZ Jack Mackerel

7.69

0

0

n/a

0

57

0.68

1.8

4.3

NZ Rock Lobster

99.53

0

0

n/a

0

n/a

8.75

23.6

55.1

NZ Orange roughy

14.4

0

0

n/a

0

104

1.27

3.4

8

NZ Barracouta

5.55

0

0

n/a

0

n/a

0.49

1.3

3.1

NZ Southern Blue Whiting

5.88

0

0

n/a

0

24

0.52

1.4

3.3

NZ Ling

7.26

0

0

n/a

0

36

0.64

1.7

4

NZ snapper

12.6

0

0

n/a

0

n/a

1.11

3

7


* Eutrophication potential = measure used in life cycle assessment to calculate impacts due to excessive levels of macronutrients in the environment caused by emissions of nutrients to air, water and soil. Expressed as equivalent kg of phosphate (PO4).

** Acidification potential = contribution to acidic substances to air, water and soils that are implicated in a range of environmental threats including acid rain, soil acidification and changing pH of soils and water. Typical substances are: sulphur dioxide (SO2), nitrogen oxides (NO x), ammonia (NH3). Expressed as tonnes of SO2 equivalents.

Source: Hilborn and Tellier, 2012

The role of fisheries and aquaculture in supporting the natural removal of emissions

The significant role oceans and coastal margins play in capturing and sequestering carbon is becoming increasingly understood and recognized. It is estimated that around 93 percent of global carbon is stored in aquatic systems, and around 30 percent of annual emissions are sequestrated in aquatic environments, primarily in mangroves, seaweeds, seagrasses, floodplain forests and coastal sediments (Nellemann et al., 2009). To improve the sector’s capacity to remove emissions, it is of primary importance to halt the disruption of carbon sequestration caused by habitat destruction and improve the often inadequate management of fisheries and aquaculture. Secondly, there may be valuable opportunities to enhance sequestration by expanding planted areas of mangroves and floodplain forests. This expanded planting would also lead to healthier ecosystems and a greater abundance of aquatic species, which would contributed to improving the quantity and quality of local and regional ecosystem services. A higher abundance of aquatic species, if managed sustainably, can provide stable livelihoods and safeguard food and nutrition security. In developing carbon funds to support greenhouse gas sequestration in aquatic systems. attention needs to be given to ensuring that communities that rely on fisheries and aquaculture are properly represented and benefit from this funding.

There is also potential to explore the role of aquaculture in carbon sequestration. Primary options include integrated multitrophic aquaculture (IMTA), where molluscs and seaweeds are grown as by-products using waste from more intensive aquaculture; and systems where the sediments in aquaculture cages or ponds are managed to enhance sequestration. Although these systems offer potentially valuable means of storing carbon, removing the carbon over the long term would require more secure means of disposal.

The role of fisheries and aquaculture in providing alternative energy sources

There is tremendous technical and environmental interest in developing renewable aquatic energy. Options include aquatic substrate biofuels, hydropower and other aquatic-based energy systems that exploit the energy potential of tides, currents, waves and wind. There are also opportunities for the physical integration of aquatic-based energy systems with newly developing infrastructure, such as offshore wind and wave installations. There is particular interest in algal biofuels based on either microalgae, which are typically cultivated in coastal ponds or intensive stirred tank systems, or macroalgae (seaweeds), which is grown in conventional culture systems. The use of microbial enzymes to produce fuels, such as bio-ethanol and biodiesels, is an already established practice, and efficiency and yields are increasing. This is particularly the case with genetically engineered bacterial enzyme systems capable of digesting celluloses and, in some cases, converting it direct into biofuel. Genetically engineered algae are also a possibility, but they would require more expensive containment and biosecurity systems. The costs of producing and harvesting algal raw materials are currently too high to make production viable for any of the proposed systems and fuel routes. However, as oil prices rise and production efficiencies improve, this procedure may become more attractive. It should be noted that, as is the case for terrestrial biofuels, algal biofuels will only provide an emission displacement function; they will not lead to a net sequestration of carbon.