Guðrún Bjarnadóttir Bech sings to herself while she sorts through baby fish with a pair of tweezers. “Ding! Ding! Ding!” she suddenly bursts out. “That’s a plaice,” she says – her reaction testament to how few she sees.
It is 2021 and Bech is working onboard the Jákup Sverri, a Faroese marine research ship that’s trawling for juvenile fish around the Faroe Islands in the north Atlantic to assess the state of populations including haddock, sand eel and Norwegian pout.
But there is one juvenile the scientists onboard are desperate to find: cod. The babies are minute, each measuring between 2mm and 25mm (0.08in to 1in). The smaller the individual, the more difficult it is to distinguish between different species. But as cod grow, their eyes and heads get bigger, and their skin, though still quite transparent, turns grey-green.
Two decades ago, cod numbers were such that the International Council for the Exploration of the Sea recommended fishing up to 32,000 tonnes in the Faroe Shelf. This year, populations are so small the council has advised no fishing for two years.
Faroese cod is not the only species of the fish that is suffering: all over the world, numbers are reaching critical lows. There are approximately 20 distinct cod populations in the north Atlantic, yet only two are plentiful: one in the Barents Sea and the other Icelandic.
Historically, overfishing was the main reason cod numbers plummeted. But now, scientists warn that warming waters are having dire effects on their ability to reproduce. Indeed, some worry that the climate emergency will make it impossible for certain cod populations to fully recover.
The fuss about cod is not simply economic or biological but also because the fish has such cultural value, according to Tara Marshall, senior lecturer at the University of Aberdeen and co-author of a paper on how the climate crisis is affecting cod.
Cod is arguably one of the most culturally important fish in the western world. It is not only the basis of one of Britain’s favourite dishes; Mark Kurlansky, author of a book on the species, claims it fuelled the Viking conquerers and was a catalyst in world wars. Fishers from the Basque Country found the Americas before Columbus, Kurlansky believes, because they were looking for cod in Newfoundland.
In southern European countries, bacalao (salt cod) has become a staple of Friday fasting and the Roman Catholic observance of Lent. The hunger for cod in mainland Europe and the UK was once the basis for the national economies in Iceland and the Faroe Islands. And Icelandics still boast about their victory in the “cod wars” – a dispute about fishing rights with the UK that took place over two decades beginning in the 1950s.
There has never been such low productivity with such a great spawning stock
But the climate emergency is wreaking havoc. Studies show that cod do not spawn in waters warmer than 9.6C (49F) – but even before that point, reproduction is affected. “Stocks [in Irish and Scottish waters] have not necessarily hit that target of 9.6, but they’re already having a reduced productivity,” says Geir Huse from the Institute of Marine Research in Norway, who also contributed to the research on climate breakdown and cod numbers.
Once caught, cod is transported around the world. But when alive, the fish is loyal to local grounds: Faroese cod spawn and live within the Faroe Shelf; Icelandic cod within Icelandic waters. The species do not interact, and the climate crisis affects them differently.
“The southernmost stocks – the Irish Sea, the Celtic Sea and the southern North Sea – are already struggling,” says Huse.
Even in the Barents Sea, where the water temperature is good for cod spawning, there is a worrying trend. Numbers peaked in 2013 and have been declining since, as juvenile fish fail to replenish the population. “There has never been such low productivity with such a great spawning stock,” says Huse, who speculates that the ecosystem in the Barents Sea must be affecting the fish.
Katie Longo, principal scientist at the Marine Stewardship Council, which sets the benchmark for sustainable fisheries, is also worried about the prospects for cod in colder waters. “The expectation is in the future there might be issues with prey availability and eventually probably also with reproductive potential that we’re not seeing yet,” she says.
Among the complexity of oceanic ecosystems, there is one key takeaway: if the number of new fish each year is reduced, the catch has to go down. Petur Steingrund, head of the demersal department at the Faroe Marine Research Institute, studies fish that live on or near the bottom of the sea. He says: “You could have a big stock but only be able to preserve it if you take a small number of fish from it each year.”
Fishers are already noticing changes in the ocean. “It’s my 22nd season, and I have never seen this small amount of cod on the echo sounder in the area where I fish,” says Tom Vegar Kiil, from Rotsund in northern Norway. New species, such as mackerel, are also turning up and he worries that they are competing with the cod for food.
A few weeks ago Vegar Kiil went fishing with his daughter, and it struck him how the cold breeze from the glaciers – a feeling he remembered so vividly from his childhood – was gone. “Something is happening, for sure,” he says.
In Fraserburgh, on the east coast of Scotland, David Milne says that when he started fishing 44 years ago, haddock and cod made up about 80% of his catch. Today, it does not make sense to target cod because the quotas are so low.
Despite catch limits, some experts suggest cod populations are still being overfished. Far more cod than is recommended by science is being caught as accidental bycatch, says Jonny Hughes, senior UK marine policy manager at the Blue Marine Foundation.
Because cod are unable to spawn in warmer waters, it is only a question of time until all populations will be affected. According to Marshall, the focus should now be on how fishers can adapt and catch new species such as sardines and tuna that are turning up in UK waters, rather than dreaming of the old days when cod was plentiful. “Why would you wish for something that’s not going to happen?” she asks.
Back onboard the Jákup Sverri there was no good news: the crew found very few of anything. Lead scientist Helga Bára Vang’s report for 2021 and 2022 showed the juvenile cod catch was below average, not auguring well for its recovery.
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However, since then, there have been some glimmers of hope. In 2023, the catch of juvenile cod by the Jákup Sverri was slightly above average for the first time since 2017. And after decades of practically no fishing, the Faroe Bank cod – known for its large size and fleshiness, although its numbers are small – has recently shown signs of recovery.
Steingrund is hopeful some populations can be saved: “At least for a while, until the global oceans have heated a couple of more degrees.”