Image copyright FAO/S.Kambou Image caption Globally, fish provided 6.7% of all protein consumed by humans, the FAO report estimated

Global per capita fish consumption has hit a record high, passing the 20kg per year mark for the first time, United Nations data has shown.

The Food and Agriculture Organization (FAO) report said it was the result of improved aquaculture and reduced waste.

It added that people, for the first time on record, were now consuming more farmed fish than wild-caught fish.

However, the report's authors warn that marine natural resources continue to be overharvested at unsustainable levels.

The data has been published in the FAO's biennial State of the World's Fisheries and Aquaculture (Sofia) report.

Manuel Barange, director of FAO Fisheries and Aquaculture Policy and Resources, welcomed the fact that global per capita fish consumption has passed the 20kg per year threshold.

"I personally think this is a very good thing because it shows that over the past five decades, fisheries supply - which combines aquaculture, inland fisheries and marine fisheries - has outpaced human population growth very significantly," he said.

"This is very significant because fisheries have a very much smaller footprint than other main sources of animal protein," he told BBC News.

"Fish is six times more efficient at converting feed than cattle, and four times more efficient than pork. Therefore increasing the consumption of fish is good for food security.

Image copyright FAO/S.Gapon Image caption Fish provide an essential source of income, as well as vital nutrition, in many parts of the developing world

The growth in aquaculture has been identified as a key driver in boosting the global per capita consumption levels of fish. In the 1960s, the figure was an average of 9.9kg; in the 1990s, it was in the region of 14.4kg.

Mr Barange said the global aquaculture sector provided 74 million tonnes of fish products. Half of this production came from "non-feed" sources, which were species that did not require additional feeding in order to grow, he explained.

"That is quite important because when aquaculture started to develop as an industry, there were concerns that it would require feeding from, essentially, marine fish turned into fish meal," Mr Barange told BBC News.

"That in itself, the concern was, would be enough to undermine marine fisheries. But, actually, half of the aquaculture production does not need feeding at all."

Growing appetite

He added that another factor for the boost in the per capita figure was a result of more fish products being used for human consumption, rather than being diverted to feed animals etc.

"In the 1960s, we used to eat about 67% of the fish we caught and cultured. Currently, it is about 87%," he said.

"Improving consumption, improving the value chain and reducing losses, combined with aquaculture growth, is what has allowed us to reach this milestone."

Mr Barange said that the FAO was working with its member countries to develop guidelines for sustainable aquaculture that they can implement in their national policies.

"In the initial boom of aquaculture production, there was little attention paid to the underlying environmental impacts. This has improved over time," he observed.

"Clearly, there are still cases where aquaculture is causing damage to habitats but there are a large number of aquaculture industries that are developing in ways that are seen as sustainable."

Image copyright FAO Image caption Global trends in the state of world marine fish stocks since 1974

While there were positive signs from the global aquaculture sector, the FAO Sofia report showed that life beneath the waves was not improving overall.

"Based on FAO's analysis of assessed commercial fish stocks, the share of fish stocks within biologically sustainable levels decreased from 90% in 1974 to 68.6% in 2013. Thus, 31.4% of fish stocks were estimated as fished at a biologically unsustainable level and therefore overfished," it reported.

Mr Barange said it was vital to continue to push for sustainability in the fisheries and aquaculture sector because it was an important source of employment and trade.

"There are about 57 million people that are engaged primarily in fishing; 80% of them are in Asia," he said.

"About 12% of the world's population rely on the fishing industry for their livelihoods. The majority of these people are in the developing world."

He added that trade in fish had grown exponentially in recent decades: "In 1976, fish exports amounted to only US $8bn. In 2014, it had reach US $148bn.

"Of this total, US $80bn was directly improving the finances of developing countries. That amount is higher than the net trade revenues of meat, tobacco, rice and sugar combined.

"The role that fish and fisheries play in economies and labour markets, particularly in the developing world, is very often understated. But it is extremely important.

"It is in this context that we want to improve the sustainability of these resources because so many of the poorest people on Earth depend on those resources."

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