In 2016, aquaculture production reached 80 million metric tons (mmt), according to the latest report, The State of the World Fisheries and Aquaculture 2018, from the United Nations’ Food and Agriculture Organization, FAO. Leading the global rankings is China, with an output of more than 49 mmt.
Total global fish production in that year was 171 mmt, including 79.3 mmt from marine fisheries, and 11.6 mmt from freshwater fisheries. FAO estimates that by 2030, total output will increase by 18 percent to reach 201 mmt.
Aquaculture will continue to expand in the coming decades, particularly in Africa, although the rate of growth has slowed from an annual rate of 10 percent in the 1980s and 1990s to an average 5.8 percent between 2010 and 2016.
Challenges ahead for the aquafeed sector
Aquaculture will need to fill the gap between growing global demand and supplies as more fishery stocks approach — or even exceed — the level of sustainable fishing, says the report.
FAO highlights that the sector’s main challenges are the resources — such as space and feed — consumed by the sector, its products, and external threats such as climate change and diseases.
Greater intensification of production in aquaculture means that, by 2016, 48 percent of total output relied on exogenous feed, and this is increasingly taking the form of commercially manufactured aquafeeds. Production of such diets increased by a factor of six between 1995 and 2015, from 8 mmt to 48 mmt.
Of all aquafeed production, 31 percent is used for carp production, with the other largest species groups being tilapia (17 percent), shrimp (15 percent), catfish (11 percent), and salmon (7 percent), according to the FAO’s estimates.
The use of wild fish for the manufacture of fishmeal and fish oils has been in decline over recent years as inclusion rates have increased for ingredients based on plants and waste fish. Improvements in feed conversion ratio by farmed species have also contributed to this trend. Marine shrimp culture is the largest user of fishmeal and fish oils in the aquafeed sector, the report says.
Despite the rapid growth of aquaculture, the sector has relatively little environmental impact in terms of greenhouse gas emissions at just five percent that of agriculture.
As fishmeal and fish oil inclusion in aquafeeds continues to decline while production levels rise, the future sustainability of aquaculture will be ever more closely linked to supplies of land-based sources of protein, oils and carbohydrates, states the FAO report. This factor is driving the exploration for novel feed ingredients for aquafeeds, including microbial seaweeds and insects.