Resource Use Efficiency in Aquaculture: Examining the Known and Unknown

The world’s human population is continuing to increase, with a recent UN projection of global population in 2050 of 9.6 billion. That would be a 33.3 percent increase above the current global population of about 7.3 billion. In many countries, economic conditions are improving; it is anticipated that the middle class will grow by 2.6 billion by 2050 (Ward and Neumann 2012). The middle class has more money to spend and they tend to purchase more food, especially protein, than do poorer people. Increasing food production will require more land and water, greater intensification, or both. It also will require more nutrients, energy and other resources and cause more negative impacts. It is imperative that the necessary increase in food production be done as efficiently as possible to minimize resource use and wastes. Programs for improving performance and lessening negative environmental impacts of global food production are important to promote more efficient food production (Clay 2004, WWF 2014). Agriculture has intensified greatly; since 1960, food production has roughly tripled but total agricultural land use has increased by only 10 percent (Boyd et al. 2013). Among other factors, the use of freshwater for irrigation, fertilizers to promote crop growth, energy for mechanization and chemicals for disease and pest control have increased, along with associated environmental perturbations. However, most authorities seem to realize that further intensification of traditional agriculture is necessary, but it must be done sustainably. Assuming the status quo for per capita consumption, demand for fisheries products — like population — will increase by 33.3 percent by 2050, but capture fisheries has reached its limit and the increase in demand for seafood must come from aquaculture. Based on recent statistics, the world production of seafood (excluding aquatic plants) is 159 t, of which 67 t are from aquaculture (FAO 2014). The status quo demand for fisheries products in 2050 will be 212 t with 120 t coming from aquaculture, an increase of about 80 percent, but the actual demand likely will be greater. Intensification also is occurring in aquaculture but many environmentalists and aquaculture professionals have not fully embraced the need for it. The desirability of better practices is widely acknowledged (Boyd et al. 2013) but there is a reluctance to accept highly-intensive aquaculture as a desirable approach. The proliferation of aquaculture eco-label certification programs provides an opportunity to assess the benefits of better practices and to evaluate the advantages and disadvantages of intensification. Much can be learned about the benefits of better practices and the wisdom of intensification by comparing the performance of certified and non-certified aquaculture production facilities across a range of culture species, production methodologies and production intensities in several major aquaculture countries. Efforts to improve the environmental performance of aquaculture typically are broad, taking into account a generally accepted list of resource use concerns and negative impacts, both great and small. Some aquaculture impacts are more serious than others and the greatest benefits accrue from adoption of better practices and achieving performance levels that measurably reduce the major impacts. The number of producers participating in aquaculture improvement and eco-label certification programs is increasing but products produced under these schemes represent a relatively small portion of the global production of certain internationally-traded species (Boyd and McNevin 2010, 2015). Several factors restrain growth of aquaculture improvement and eco-label certification. The market for these products is comparatively small and marketing specialists often do not realize the potential long-term economic benefit of promoting responsible aquaculture. Those marketing aquaculture products need sound documentation that improved performance will provide marketing advantages. There also is little to no demand for responsible aquaculture products in domestic markets in developing countries. Finally, producers usually do not receive a price premium for products of responsible aquaculture, only access to certain markets or increased net profits by becoming more efficient and productive. This raises a much greater concern. Should consumers be able to choose between a responsibly produced product and an irresponsibly produced one or should all products provided to consumers be responsibly produced? Most resource use, waste generation and other negative impacts of aquaculture occur at the farm level (Clay 2004, 2008, Boyd et al. 2013, Boyd and McNevin 2015). The purpose of this article is to discuss the crucial need for developing a better understanding of the efficiency of resource use at the farm level to provide a sound basis for promoting better performance on