Due to stronger aquaculture supply and firm demand, record hauls for some key species and reduced wastage, global per capita fish consumption has risen above 20 kilograms for the first time according to a new FAO report.
Yet, despite notable progress in some areas, the state of the world's marine resources has not improved. The latest edition of the UN agency's The State of World Fisheries and Aquaculture
(SOFIA) says that almost a third of commercial fish stocks are now fished at biologically unsustainable levels, triple the level of 1974.
Global total capture fishery production in 2014 was 93.4 million tonnes, including output from inland waters, up slightly over the previous two years. Alaska pollock was the top species, replacing anchoveta for the first time since 1998 and offering evidence that effective resource management practices have worked well. Record catches for four highly valuable groups - tunas, lobsters, shrimps, and cephalopods - were reported in 2014.
There were around 4.6 million fishing vessels in the world in 2014, 90 percent of which are in Asia and Africa, and only 64,000 of which were 24 meters or longer, according to SOFIA.
Globally, fish provided 6.7 percent of all protein consumed by humans, as well as offering a rich source of long-chain omega-3 fatty acids, vitamins, calcium, zinc and iron. Some 57 million people were engaged in the primary fish production sectors, a third of them in aquaculture.
Fishery products accounted for one percent of all global merchandise trade in value terms, representing more than nine percent of total agricultural exports. Worldwide exports amounted to $148 billion in 2014, up from $8 billion in 1976. Developing countries were the source of $80 billion of fishery exports, providing higher net trade revenues than meat, tobacco, rice and sugar combined.
"Life below water, which the Sustainable Development Agenda commits us to conserve, is a major ally in our effort to meet a host of challenges, from food security to climate change," FAO director-general José Graziano da Silva. "This report shows that capture fisheries can be managed sustainably, while also pointing to the enormous and growing potential of aquaculture to boost human nutrition and support livelihoods with productive jobs."
That the global supply of fish for human consumption has outpaced population growth in the past five decades - preliminary estimates suggest per capita intakes higher than 20 kilograms, double the level of the 1960s - is due in large measure to growth in aquaculture.
The sector's global production rose to 73.8 million tonnes in 2014, a third of which comprised molluscs, crustaceans, and other non-fish animals. Importantly in terms of both food security and environmental sustainability, about half of the world's aquaculture production of animals - often shellfish and carp - and plants - including seaweeds and microalgae - came from non-fed species.
While China remains by far the leading nation for aquaculture, it is expanding even faster elsewhere, the report notes. In Nigeria, aquaculture output is up almost 20-fold over the past two decades, and all of Sub-Saharan Africa is not far behind. Chile and Indonesia have also posted remarkable growth, as have Norway and Vietnam - now the world's No. 2 and No. 3 fish exporters.
Aquaculture's strengths and challenges are also influencing what fish end up on our plates. The report shows that, measured as a share of world trade in value terms, salmon and trout are now the largest single commodity, an honor that for decades belonged to shrimp.
The state of sustainability
Some 31.4 percent of the commercial wild fish stocks regularly monitored by FAO were overfished in 2013, a level that has been stable since 2007. FAO's methodology is consistent with international agreements stating that fish stocks should be maintained at or rebuilt to a size that can support Maximum Sustainable Yield (MSY). Thus, stocks are classified as being fished at biologically unsustainable levels - overfished - when they have an abundance lower than the level that can produce the Maximum Sustainable Yield.
Decreased fish landings have been observed in some regions due to the implementation of effective management regulations, like in the Northwest Atlantic, where the annual catch is now less than half the level of the early 1970s. Halibut, flounder and haddock stocks in that area are showing signs of recovery, although that is not yet the case for cod.
Management measures also appear to be working for the highly-priced Patagonian toothfish - a type of whitefish from Antarctica often marketed (in US restaurants) as Chilean sea bass - as the catch of that fish in Antarctic waters has been stable since 2005. Catches of Antarctic krill, which feed directly on phytoplankton, jumped substantially to levels not reached since the early 1990s while being maintained at sustainable levels.
The report described the situation in the Mediterranean and Black Sea - where 59% of assessed stocks are fished at biologically unsustainable levels - as "alarming". This is especially true for larger fish such as hake, mullet, sole and sea breams. In the Eastern Mediterranean, the possible expansion of invasive fish species associated with climate change is a concern.
FAO continues to work with all countries to improve the quality and reliability of annual landing figures. The doubling since 1996 of the number of species in the FAO database - now 2,033 - indicates overall quality improvements in the data collected, according to the report. Supply-chain and other improvements have also raised the share of world fish production utilised for direct human consumption to 87 percent or 146 million tonnes in 2016, according to the report. That's up from 85 percent or 136 million tonnes in 2014.
The growing fish-processing sector also offers opportunities to improve the sustainability of the fish supply chain, as a host of byproducts have multiple potential and actual uses, ranging from fishmeal for aquaculture, through collagen for the cosmetics industry to small fish bones humans can eat as snacks.