March 24 (UPI) — Aquaculture has come a long way over the last few decades, becoming more sustainable and efficient.
But to deliver on its promise to ease pressures on land and ocean resources, a new survey suggests the aquaculture industry requires a combination of innovation and oversight.
In their paper, published Wednesday in the journal Nature, a team of researchers offer a 20-year retrospective on developments in global aquaculture, as well as recommendations for how the industry can boost sustainability, while remaining economically viable.
“As the demand for seafood around the world continues to expand, aquaculture will keep growing,” lead author Rosamond Naylor said in a news release.
“If we don’t get it right, we risk the same environmental problems we’ve seen in land-based crop and livestock systems: nutrient pollution, excessive use of antibiotics and habitat change that threatens biodiversity,” said Naylor, a professor of Earth system science at Stanford University.
More than twenty years ago, Naylor lead an investigation of fish farming’s environmental impacts. The research showed fish farms — which require large amounts of wild fish for fish feed — might do more harm than good.
Since then, the industry has grown rapidly — and the latest research suggests fish farms have become much more sustainable.
“Pressure on the aquaculture industry to embrace comprehensive sustainability measures during this 20-year period have improved the governance, technology, siting and management in many cases,” researchers wrote.
The sheer size and scope of global aquaculture is one of the biggest takeaways of the newly published retrospective. Many people think of farm-raised salmon when they think of aquaculture, but the industry is dominated by freshwater species.
According to the latest findings, freshwater aquaculture — of which there are more than 150 species of fish, shellfish and plants — accounts for 75 percent of farmed aquatic food eaten by humans.
“Most aquaculture is about fish people can afford to eat — and most of the farming of aquatic animals happening in Asian countries stays in those countries,” said study co-author David Little.
“It’s having an important impact on food security and rural livelihoods,” said Little, a professor at the University of Stirling Institute for Aquaculture in Britain.
Aquaculture industries in Asia and Africa have grown significantly over the last two decades, often with little oversight. Researchers suggest policy makers must take steps to ensure the industry’s rapid growth doesn’t undermine sustainability.
Since 1997, the ratio of wild fish input to fed fish output has been reduced seven-fold — in other words, fish farms are putting less pressure on natural resources.
However, the industry faces a variety of other environmental problems, including the overuse of antibiotics and cross-contamination between fish waste and surrounding waters.
“When done well, aquaculture can play a sustaining role in global food systems by providing expanded food production and livelihood benefits with relatively minimal environmental harm,” said study co-author Dane Klinger.
“This assessment will help industry, government and other stakeholders navigate the opportunities and obstacles that remain ahead,” said Klinger, director of aquaculture at Conservation International.