22 SEPTEMBER 2013 • WORLD AQUACULTURE • WWW.WAS.ORG to global seafood needs (Fig. 10), from less than 10 percent in the 1970s to about 50 percent of what we consume now. This trend will continue as demands increase and fisheries stocks are exploited near or greater than maximum sustainable yields. Calculations based on present per capita consumption and estimated population size 10 years from now reveal that aquaculture will have to provide more than 25 percent more on an annual basis within the next decade. Considering the available global resources for food extraction or production, it is clear that land for crops and pasture will come under serious pressure (Fig. 11). However, the vast area of seas and oceans could be better explored and exploited for mariculture development and eventually play a much more important role in the production of food for humanity. Global primary production is as important in the seas and oceans as it is on land, however, today the marine environment contributes less than 2 percent of the total quantity and only 16 percent of protein to our food supply (Fig. 12). It is largely for historical reasons that aquaculture production today is only slightly greater in marine waters as compared to freshwater habitats (Fig. 13). In future decades we can expect and in fact should promote a significant shift to farming the oceans and seas. It should be clear that aquaculture is expected to expand very significantly. However, can this be achieved following our current expertise and experience? Can it be accomplished without causing environmental risks or human health problems? The answer is yes but only when we shift into a higher gear. We cannot continue along the empirical path of the past. Perhaps this has been an appropriate approach until now, i.e., trial and error using sound scientific principles. However, with the challenges ahead, we need to develop a more knowledge-based bio-industry. We need to understand the underlying mechanisms of all biological processes responsible for the final production outcome. Only then we can develop a more predictable, reliable, cost-effective and ultimately more sustainable industry. Priority Needs for Future Aquaculture In Table 1 (Fig. 14) I propose a long list of what I consider to be the priority needs for future aquaculture. Most of these are discussed in greater detail in FAO/NACA (2012). Priority 1 – Domestication. The lack of domestication in aquaculture has placed us many years behind terrestrial animal farming. For many if not most aquatic species, we are still hunting for wild breeders or seed with all the consequences of introducing a lot of variability, i.e. a year of good performers versus a year of poor stock, eventually carrying parasites or even commensals that can turn into nasty pathogens under farm conditions. Priority 2 – Seed Production. Although many billions of fish and shellfish offspring are produced in more or less sophisticated hatcheries, seed production of delicate aquatic organisms remains a challenge. The predictability of production and especially cost-efficiency can be improved a lot. Consider the example of seabass and seabream hatcheries in the Mediterranean, a sector with an annual turnover of more than 150 million euros. With current levels of survival of only 20 percent at 60 days after hatching, there is much room for improvement. This is not only a concern from a cost-efficiency perspective but also for environmental and overall sustainability reasons. FROM TOP TO BOTTOM. FIGURE 10. Contribution of aquaculture to world food-fish consumption in 1970-2008 (courtesy Rohana Subasinghe, FAO-Rome, 2010). FIGURE 11. Earth’s surface distribution and uses (courtesy Patrick Cunningham, as presented at the workshop “Knowledge Based Bio-Economy towards 2020”, Brussels, 14 September 2010). FIGURE 12. Global primary production and food supply (after Field et al. 1998 and Duarte et al. 2009). FIGURE 13. Aquaculture production by species group and environment (FAO - the State of Aquaculture 2010).
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