Researchers have raised a genetically engineered crop on land that contains certain nutrients found only in fish oil and algae, and it's hoped that the breakthrough could help the fish-farming industry keep growing.
The development is a step toward developing a sustainable source of Omega-3 fatty acids for the large and growing global fish farming industry, which is exhausting all other sources of the needed nutrients, say researchers from UK-based laboratory Rothamsted Research.
The group published the results this week in the journal Metabolic Engineering Communications.
Fish farming is a booming industry. More than half of all of the seafood people eat around the world comes from fish farms, according to the National Oceanic and Atmospheric Administration, and the agency expects that percentage to rise further.
The global industry is worth somewhere around $100 billion annually, according to NOAA. In 2013, data showed that the world farms more fish than beef, according to the New Scientist. Fish farming accounted for about 57 million tons of fish in 2010 and will farm 93 million tons by 2030, according to the United Nations Food and Agriculture Organization.
That may not be a bad thing, said Johnathan Napier of Rothamsted Research, one of the researchers who worked on the project.
"The fish farming industry gets bad press because it is viewed as not being sustainable. When you compare the inputs it is far more efficient than almost any terrestrial livestock farming," Napier told CNBC.
He said farmed fish holds a lot of promise as an affordable protein source for the world, and health authorities praise fish for being nearly unique sources of a group of nutrients called Omega-3 fatty acids.
Omega-3 acids have been linked to lower risks of heart disease and cholesterol problems and other health benefits. Some Omega-3 fatty acids, such as ALA (alpha-lipolenic acid) can be found in plants, including nuts and seeds, such as the health store fixture called flax seed. But other Omega-3 acids, such as EPA and DHA, originate in ocean algae. Algae-eating fish and other sea animals build up stores of the nutrients and pass them on to the larger predatory fish that eat them.
Therein lies the problem for farmers. The ocean is a "soup of Omega-3" acids, Napier said, but the diets that fish farmers feed their stocks often require supplemental Omega-3 oils in the form of oil extracted from other fish.
In fact, the fish farming industry's demand for fish oil is so great that about 80 percent of 1 million metric tons of oil extracted from fish every year goes right back into fish feed, Napier said. And the industry is running out of oil.
"I would argue that fish farming is relatively sustainable, but the problem is that the fish farming industry has grown 6 percent year over year, and it will soon be constrained by the amount of available fish oil, if it hasn't been already," Napier told CNBC. "In fact, some research from Australia and Scotland has shown that farmed fish already are being fed lower and lower levels of oil, and that means the filet on your plate will have less fish oil in it."
There are few alternatives currently available. In theory, fish farmers could just feed their stocks marine algae, but Napier said algae production is still a small industry, and lacks the infrastructure to meet demand now. Algae production also requires processes such as fermentation that make it more expensive to scale up than an agricultural product, he said.
Rothamsted Research, which is a publicly funded institution classified as a charity in the United Kingdom, has been working on a plant-based source of Omega-3 acids for 10 years, Napier said. Over the last decade, the team has moved the crop from a laboratory to greenhouses, and now, to a field. The team has also successfully tested the product in farmed salmon feed, he said.
The crop can fail at any stage of that process. Rothamsted made news in June when another genetically modified crop—a pest-resistant form of wheat—failed to perform as expected in one of its field trials.
Napier said his team was excited by the positive result.
The researchers are already running a slightly larger field trial that they will complete in the next year. They then will likely test the crop in different environments and climates, and their aim is to create plants that can survive in places close to fish farms, such as Canada or Chile, Napier said.
The team chose Camelina sativa, which Napier calls a "cousin of canola." The crop worked for them because it is relatively easy to genetically modify, does not cross-pollinate with closely related crops, and requires less fertilizer than canola. It also is being farmed for biofuel in some places, including the United States, so producers already have methods for efficiently extracting the oil from the plant.
It further trials are successful, Rothamsted will decide how it will distribute the technology to farmers.
CORRECTION: An earlier version of this article incorrectly stated fish farming numbers taken from a United Nations report.