The contribution of fisheries and aquaculture to the global protein supply

Food Security https://doi.org/10.1007/s12571-021-01246-9 ORIGINAL PAPER The contribution of fisheries and aquaculture to the global protein supply Claude E. Boyd1 · Aaron A. McNevin2 · Robert P. Davis1 Received: 15 June 2021 / Accepted: 6 December 2021 © The Author(s) 2022 Abstract The contribution of aquatic animal protein to the global, animal-source protein supply and the relative importance of aquaculture to capture fisheries in supplying this protein is relevant in assessments and decisions related to the future of aquatic food production and its security. Meat of terrestrial animals, milk, and eggs resulted in 76,966 Kt crude protein compared with 13,950 Kt or 15.3% from aquatic animals in 2018.While aquaculture produced a greater tonnage of aquatic animals, capture fisheries resulted in 7,135 Kt crude protein while aquaculture yielded 6,815 Kt. Capture fisheries production has not increased in the past two decades, and aquaculture production must increase to assure the growing demand for fisheries products by a larger and more affluent population. We estimated based on status quo consumption, that aquaculture production would need to increase from 82,087 Kt in 2018 to 129,000 Kt by 2050 to meet the demand of the greater population. About two-thirds of finfish and crustacean production by aquaculture is feed-based, and feeds for these species include fishmeal and fish oil as ingredients. Aquaculture feeds require a major portion of the global supply of fishmeal and fish oil. An estimated 71.0% of fishmeal and 73.9% of fish oil are made from the catch with the rest coming from aquatic animal processing waste. The catch of small, pelagic fish from the ocean is not predicted to increase in the future. Aquaculture should reduce its fishmeal and oil use to lessen its dependency on small wild fish important to the integrity of marine food webs and food security for the poor in many coastal areas. Fishmeal and fish oil shortages for use in aquaculture feed will result in a limit on production in the future if goals to lessen their use in feeds are not met. Keywords Animal-source protein · Aquaculture production · Capture fisheries production · Global protein production · Resource use efficiency · Animal feeds 1 Introduction Agriculture has provided humans with terrestrial, animalsource food for at least 5,000 years (Larsen, 2003; Modlinska & Pisula, 2018), but fish and other aquatic animals have traditionally been caught from the ocean and inland waters. Farming of aquatic animals has been done for more than 2,000 years, although this practice did not become a noticeable factor in global meat production until the twentieth century (Stickney, 2000). Global aquaculture production has increased rapidly since the 1950s while global capture fisheries production has * Claude E. Boyd 1 School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama 36849, USA 2 World Wildlife Fund, Washington, D.C, USA shown no trend of increase after the early 1990s (Fig. 1). Aquaculture production surpassed capture fisheries production for human consumption in 2016 (FAO, 2020a), and it contributed 52% of the total harvest weight of aquatic animals for human consumption in 2018 (FAO, 2020a, c). The amount of consumed meat from an animal is less than the animal’s weight because certain of its parts are not suitable for food or are not preferred for food (Boler & Woerner, 2017; Wright, 2016). The importance of differences in meat yields of animals is evident from a study by Edwards et al. (2019) in which they found that although aquaculture production of animals for human consumption exceeds capture fisheries production, more meat was produced by the capture fisheries as a result of differences in meat yield among different species within the two sectors. Meat is important in human diets because a dietary portion of it typically has a higher protein concentration with a better balance of essential amino acids than does an equal 13 Vol.:(0123456789) C. E. Boyd et al. Fig. 1  World production of capture fisheries and of aquaculture from 1950 to 2018 (source: FAO, 2020a) size portion of a plant-source food (Wyness, 2016, McNeill et al., 2017; Klurfeld, 2018; Tilami & Samples, 2018). Milk and eggs have lower protein concentrations than do meats, but they have an excellent balance of essential amino acids (Muehlhoff et al., 2013; Nassar, 2016). The supply of protein available to humans is a critical factor in global food security (Henchion et al., 2017), and information about the contribution of aquatic animals to food supply is relevant to a better understanding of this aspect of the world food system. According to FAO (2020c), aquaculture and fisheries combined accounted for 17% of total animal-source protein for human consumption. The FAO statement did not separate the protein contribution of capture fisheries and aquaculture to the supply. It is important to know the contribution of each of the two sources of aquatic animal protein, and the amounts of protein from each of the major animal groups, i.e., fish, crustaceans, and molluscs, of capture fisheries and of aquaculture. Oceans are overfished (FAO, 2020c; Sumaila & Tai, 2020), but there are those (such as Duarte et al., 2009; Costello et al., 2020) who propose that mariculture (ocean aquaculture) in combination with adequate ocean conservation measures would allow the ocean to provide more protein for humans in the future. There is scant prospect for increasing the capture from the ocean while applying the current methods of fishing (Costello et al., 2020). The changing climatic conditions are expected to worsen in years to come, and this challenge provides opportunity to create new systems of food production and to abandon or lessen the use of some systems in efforts to conserve land, water, and energy as well as to reduce greenhouse gas emissions (GHGs) or increase carbon sequestration (Campbell et al., 2016; Gephart et al., 2021; Rosenzweig et al., 2021; Thiault et al., 2019). This is important because food production uses 38% of land (FAO, 2016) and 70% of freshwater 13 (FAO, 2016), while resulting in 25–35% of global greenhouse gas emission (IPCC, 2013; Tubiello et al., 2014). Capture fisheries and aquaculture are rather minor components of global use of most resources. Boyd and McNevin (2015) estimated land use by aquaculture as 0.17% of the global land area, and consumptive water use as 0.82% of renewable, available freshwater. Consumptive water use does not include the “so-called” green water (rainwater) that falls on agricultural fields and aquaculture ponds only to evaporate. Verdegem and Bosma (2009) included green water and concluded that 3.2% of global freshwater use was by aquaculture. Boyd and McNevin (2015) estimated that capture fisheries and aquaculture produced 0.61% and 0.49% of global GHG emissions, respectively. A more recent estimate by Macleod et al. (2020) also gave an e (...truncated)