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Expand the evidence base:

Support enabling frameworks:

Enhance financing options:

Implement practices in the field: 

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 Eradication^iv (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. 

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.

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:

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. 

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.