Why rising farmed salmon demand means less fish in our oceans

By Stephen Beech via SWNS

Soaring demand for farmed salmon is endangering access to local sea fish for poorer communities around the world, warns a new report.

Growing appetite for salmon in the northern hemisphere means more wild fish, not less, is being taken from the ocean, say scientists.

Their findings, published in the journal Science Advances, highlight how demand for expensive farmed salmon can leave coastal communities struggling to access affordable local fish, such as sardines and anchovies - despite industry claims to the contrary,

The research team says that the small fish are frequently caught, processed, and “reduced” to fishmeal and fish oil, almost all of which is used to feed farmed fish.

The ‘reduction fisheries’ account for 26% of global ocean catch, according to the report.

Co-author Dr. Kathryn Matthews said: “As the aquaculture industry grows, so does its dependence on wild fish.

“The continued rapid expansion of the sector will demand ever more fishmeal and fish oil, even as its use in feed becomes more efficient.”

The researchers debunk the industry’s use of the “Fish-in-Fish-out” (FIFO) ratio – the standard measure used to quantify how much wild fish is used to produce farmed fish.

The FIFO ratio is often used as an indicator of the impact of aquaculture on wild fish stocks.

The research team showcases several "misleading" practices about the FIFO ratio in the report, such as averaging fishmeal and fish oil inputs of carnivores and herbivores together to conceal the high feed requirements of carnivorous species.

The researchers say that lowers the FIFO ratio, reaffirming the aquaculture industry’s claim that its dependence on fish oil and fishmeal is reducing.

But fish oil, in particular, is a limited commodity that is increasingly in demand for salmon farms, which now supply 70% of all salmon consumed worldwide.

In 2020, farmed Atlantic salmon alone accounted for 60% of fish oil usage, according to the report.

Dr. Matthews, chief scientist at ocean conservation body Oceana, said: "The salmon industry is not a food production system – it’s a food reduction system.

"It benefits the few who can afford it, but reduces access to nutritious fish for those who need it the most.”

The research team point out, as an example, processing plants in West Africa that are exploiting vast amounts of small, highly nutritious fish, mostly sardinella, to produce fishmeal and fish oil for export.

Oceana senior analyst Dr. Daniel Skerritt said: "This is an equity issue – it puts local fishmongers at an unfair disadvantage because they cannot compete with the prices the plants are willing to pay for this global commodity."

The researchers say there is a "turbulent" future ahead for fishmeal and fish oil production as climate change is impacting fish populations around the world, including the main source of fishmeal and fish oil – the Peruvian anchoveta.

Like many others, that species in warmer waters contains less fish oil.

The team also warned that continued poor management of fisheries allows for ever higher catches of juveniles, which also contain less oil.

Co-author Professor Patricia Majluf, of the Center for Environmental Sustainability at Cayetano Heredia University, Peru, added: "Combined, these factors are driving feed manufacturers to look elsewhere for additional oil, including in fisheries which typically provide fish for direct human consumption, like mackerel."

The researchers urged the industry to utilize substitutes for fishmeal and especially fish oil in aquaculture fish feeds.