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Not enough, not soon enough: the urgent hunt for young cod fish

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.

In the year 2021, Bech is currently employed on the Jákup Sverri, a research vessel from the Faroe Islands that is surveying the northern Atlantic region for young fish. The purpose of this expedition is to evaluate the current status of various populations, such as haddock, sand eel, and Norwegian pout.

However, the researchers on board are determined to locate one specific young fish: cod. These juveniles are extremely small, ranging from 2mm to 25mm in size. The smaller the fish, the harder it is to differentiate between various species. As the cod mature, their eyes and heads increase in size and their skin, although still somewhat see-through, changes to a grey-green color.

Two men leaning over a green fishing net.

Twenty years ago, the amount of cod was at a level where the International Council for the Exploration of the Sea suggested fishing up to 32,000 tonnes in the Faroe Shelf. However, this year the population has decreased significantly and the council has advised against fishing for a period of two years.

The population of Faroese cod is not the only one facing challenges, as other cod species around the world are also declining. In the northern Atlantic, there are about 20 different populations of cod, but only two are currently thriving: one in the Barents Sea and the other in Iceland.

In the past, excessive fishing was the primary cause of the decline in cod populations. However, experts are now cautioning that rising temperatures in the water are greatly impacting their ability to breed. In fact, there are concerns that the current climate crisis may prevent certain cod communities from ever fully rebounding.

The attention surrounding cod is not solely based on economic or biological factors, but also stems from its cultural significance. According to Tara Marshall, a senior lecturer at the University of Aberdeen and co-author of a study on the impact of the climate crisis on cod, this fish holds great cultural value.

The fish known as cod holds significant cultural significance in the Western world. Not only is it a staple in one of Britain’s beloved dishes, but author Mark Kurlansky suggests that it played a role in fueling Viking conquerors and even served as a catalyst in major world conflicts. According to Kurlansky, the Basque fishers who discovered the Americas may have been searching for cod in Newfoundland.

A hand holds a baby fish trapped in a purple jellyfish over a bucket of water

Bacalao, or salt cod, is a staple in southern European countries for Friday fasting and during the Roman Catholic observance of Lent. In the past, the demand for cod in mainland Europe and the UK was crucial to the economies of Iceland and the Faroe Islands. Even today, Iceland takes pride in their success in the “cod wars,” a 20-year conflict over fishing rights with the UK that began in the 1950s.

The climate crisis is causing significant damage. Research indicates that cod cannot reproduce in waters above 9.6C (49F) – and even at lower temperatures, their reproductive abilities are impacted. Geir Huse from the Institute of Marine Research in Norway, who assisted with the study on climate change and cod populations, explains that cod stocks in Irish and Scottish waters may not have reached the critical temperature of 9.6C, but they are still experiencing reduced productivity.

After being caught, cod is shipped globally. However, while alive, the fish remains within their local grounds. Faroese cod reproduce and reside in the Faroe Shelf, while Icelandic cod are found in Icelandic waters. These two species do not cross paths and are impacted differently by the changing climate.

Baby fish lined up on metal counter top, sorted by a pair of tweezers

According to Huse, the stocks in the southern regions (Irish Sea, Celtic Sea, and southern North Sea) are currently facing challenges.

Despite the favorable water temperature for cod spawning in the Barents Sea, there is a concerning pattern emerging. After reaching its peak in 2013, the population has been steadily declining due to a lack of juvenile fish replenishing the stock. According to Huse, this is an unusual situation where there is a large spawning stock but low productivity, potentially due to the impact of the Barents Sea ecosystem on the fish.

Katie Longo, a leading scientist at the Marine Stewardship Council, is concerned about the future of cod in colder regions. As the standard setter for sustainable fishing practices, she fears that there may be challenges in finding enough food for cod and potential issues with their ability to reproduce in the future.

In the intricate ocean ecosystems, there is a crucial lesson to learn: when there are fewer new fish in a year, the fishing yield must decrease. Petur Steingrund, the director of the demersal division at the Faroe Marine Research Institute, specializes in studying fish that reside on or near the ocean floor. He explains, “Even if you have a large stock, it can only be sustained if you harvest a small amount of fish from it annually.”

View out to sea off a ship’s deck.

Fishermen are observing alterations in the sea. According to Tom Vegar Kiil from Rotsund, Norway, who has been fishing for 22 seasons, the echo sounder in his fishing area is showing a significantly reduced amount of cod. He also expresses concern about the appearance of new species like mackerel, which may be competing with cod for resources.

Vegar Kiil recently went on a fishing trip with his daughter and noticed that the familiar chill from the glaciers, which he vividly remembered from his own childhood, was no longer present. He believes that this change is a sign of something happening.

David Milne, a fisherman from Fraserburgh, Scotland, shares that 44 years ago, haddock and cod accounted for 80% of his catch. However, due to significantly reduced quotas, it is no longer practical to focus on catching cod.

Even with regulations on catch limits, there are concerns that cod populations are still being depleted due to excessive fishing. According to Jonny Hughes, senior UK marine policy manager at the Blue Marine Foundation, a significant amount of cod is being unintentionally caught as bycatch, exceeding the recommended amount advised by scientific research.

Scientist peering over sheet of paper with various baby fish species.

Since cod cannot reproduce in warmer temperatures, it is inevitable that all populations will eventually be impacted. Marshall suggests shifting attention towards how fishermen can adjust and target different species like sardines and tuna, which are now appearing in UK waters, instead of clinging to the idea of abundant cod from the past. She questions the logic of longing for something that is no longer feasible.

Upon returning to the Jákup Sverri, the crew received disappointing news – they had only managed to find a small amount of resources. The report from lead scientist Helga Bára Vang for 2021 and 2022 revealed that the catch of juvenile cod was below the expected average, indicating a potentially difficult recovery ahead.

Nevertheless, there have been some positive signs since then. In 2023, the Jákup Sverri caught more juvenile cod than usual for the first time since 2017. Additionally, the Faroe Bank cod, which is known for its large size and quality meat but has been rarely fished in the past, has started to show signs of improvement.

Steingrund remains optimistic that certain populations may be preserved, at least temporarily, until the world’s oceans increase in temperature by a few more degrees.

Source: theguardian.com