The New York Times is reporting this week on worries by the “world's foodies” over a potential “environmental mess” have eased some. The concern was that fish farms were gobbling up wild fish stocks, spreading disease and causing marine pollution.
This week, some of the same experts who published that report issued a new paper concluding that fish farming, in many parts of the world, at least, “is a whole lot better.” The most significant improvement was that farmed fish were not being fed as much wild fish. In fact, they are eating more plants, such as soy meal.
The study was highly sophisticated and synthesized hundreds of research papers over the last 20 years across the global aquaculture industry. The latest edition was published on Wednesday in the journal Nature.
The findings are seen to have “real-world implications for nutrition, jobs and biodiversity,” the Times said. Aquaculture is a source of income for millions of small-scale fishers and revenue for fish-exporting countries.
It is also vital if the world's 7.75 billion people who depend on fish and shellfish but want to avoid draining the ocean of wild fish stocks and marine biodiversity. This has led to concerns among some environmentalists about aquaculture's effects on natural habitats. The new paper found promising developments, but also lingering problems. And it didn't quite inform the average fish-eater what they should eat more of — or avoid.
The report called the aquaculture industry “too diverse for broad generalizations,” according to Rosamond Naylor, a professor of earth systems science at Stanford University and the lead author of both the 2000 cautionary paper and the review published Wednesday.
“The aquaculture industry includes over 425 species farmed in all sorts of freshwater, brackish water, and marine systems, so it doesn't make sense to lump them all together into a 'sustainable' or 'non-sustainable' category,” Naylor said. “It has the potential to be sustainable — so how can we ensure it moves in that direction?”
Global aquaculture production has more than tripled in the last 20 years, producing 112 million metric tons in 2017, the most recent year for which statistics were are cited. China leads the way, producing more than half of all farmed fish and shellfish worldwide. Outside of China, Norway and Chile are big players, producing mostly farmed Atlantic salmon, while Egypt produces mostly the Nile tilapia. Most fish produced in Asia is consumed in Asia, meaning that it serves as an important source of protein for citizens of those countries.
The study also found that the production of farmed seaweed and bivalves, like oysters and clams, had greatly expanded as well. That is perhaps the most encouraging news, because neither seaweed nor bivalves need extra food to reproduce. They filter nutrients from the water and, in turn, produce nutrition for human consumption.
The study reported that freshwater aquaculture today accounts for 75% of farmed fish directly consumed by humans. Its most striking finding, though, concerns fish feed, the Times said, especially for carnivorous fish like salmon, which were traditionally fed lots of wild fish, like anchovies. Between 2000 and 2017, the study said the production of farmed fish tripled in volume, even as the catch of wild fish used to make fish feed and fish oil declined.
Martin Smith, an environmental economist at Duke University who was not involved in the study, said the changes in aquaculture resulted partly from new regulations in some countries — rules in Norway, for instance, reduced the spread of sea lice in salmon farms — but mostly because the aquaculture industry had no reason to buy expensive wild fish feed once they had access to plant-based alternatives.
“It was always in aquaculture's interest to reduce their most expensive ingredient,” said Smith, who teaches a class called “Should I Eat Fish?” “The language around aquaculture has been overly negative and overly pessimistic,” he thinks. “But also, the industry has gotten a lot better.”
Still, problems linger, the authors of the latest study point out.
Aquaculture needs better oversight to ensure that environmentally sustainable practices are followed and rewarded. Some countries need to better manage the use of antimicrobials in fish ponds to guard against drug resistant microbes. Aquaculture also remains vulnerable to extreme climate events and disruptions in global trade, such as those created by the coronavirus pandemic. And then there's the question of where the soy used for fish farming comes from. Pressure is mounting on the aquaculture industry to ensure that it does not source soy from deforested areas like the Amazon.
“As is the case with all food systems, consumers must realize that there is no free lunch, but there are important choices that can be made with sufficient information,” Naylor said.
So, we will see. Environmentalists are rarely happy with the way the world is going — and many would prefer totally plant based diets for more people, in spite of the extent that many of these products rely on manufacturing — and in spite of the frequent criticism that often surfaces for farmed fish. As a result, ag producers probably should be happy with the modest, if growing, areas of agreement recently observed and interpret those as possible future growth markets as they do tend to be, Washington Insider believes.