It is difficult to identify exactly when commercial fishing – that is catching fish for the purpose of trade – first began (1). Analysis of fish teeth recovered from archaeological sites on the shores of the southeastern Mediterranean suggests that bream were traded between peoples in Egypt and the Levant from as early as 1,500 BC, with these trade routes continuing until the year 500 AD (2). In 2003 evidence was uncovered that showed that a catfish species which was native to the River Nile in Egypt had been transported to Sagalassos in southern Turkey, then a major Roman city (3). This showed that the Romans had well-organised trade routes to move fish that had been preserved in salt long distances around the lands they controlled (3).
The Vikings also traded fish which they had caught and preserved as early as the 9th century. Cod would be caught in Arctic waters and then hung from wooden racks, allowing it to dry out and freeze. Preserved in this way the cod would have a hard wood-like texture and would last for months. This allowed the Vikings to have sufficient food supplies to travel across the Atlantic to explore North America (4), and excess preserved cod was also traded throughout northern Europe in an early example of a commercial fishery. But it was the Basques who began the world’s first truly international fishery. They travelled from what is now northwest Spain to the coast of North America, and like the Vikings they also caught cod. But while the Vikings relied on drying cod, the Basques were able to salt the cod they caught. This made it last much longer than drying and meant the Basques could travel further than the Vikings and take much greater quantities of the cod they had caught back to Europe to sell and trade (4).
The Dawn of Trawling
In the 1300s the first sail-powered trawlers appeared with the world’s first known reference to trawling being made in 1376. This consisted of a message being sent to King Edward III requesting that a new type of trawling be banned as it was so destructive and caught so many small fish. This new development was known as the “wondryechaun” and was a type of heavy beam trawl which was fitted with a net which was described as:
“So close meshed that no fish be in it ever so small which enters therein can escape, but must stay and be taken. And the great and long iron of the wondryechaun runs so heavily and hardly over the ground when fishing that it destroys the flowers of the land below water there, and also the spat of oysters, mussels and other fish upon which the great fish are accustomed to be fed and nourished. By which instrument in many places, the fishermen take such quantity of small fish that they do not know what to do with them” (5).
As Professor Callum Roberts points out in The Unnatural History of the Sea, this first-ever historical reference to trawling was to complain about its destructive power and the number of fish that were indiscriminately taken. Roberts states that the arguments about the destruction caused by the trawl have “echoed down the centuries” and yet despite this trawling remains the most commonly used method of commercial fishing in the world.
Sail trawlers powered by the wind became increasingly common from the late Middle Ages onwards. In the 1380s the Dutch fisherman Willem Bueckelszoon (known in English as William Buckles) developed the process of preserving herring by salting them (6). This allowed herring to be traded widely and led to the emergence of the herring buss, a vessel used specifically for catching herrings, and salt became a hugely valuable commodity due to its use in preserving fish (4). This allowed the Dutch herring fishing to expand to such an extent that by the 17th century one million Dutch people were involved in herring fishing and the wider herring industry – one-fifth of the nation’s entire population (1).
Sail-powered vessels were, however, limited to fishing in the right tide and wind conditions, and the inability to preserve fresh fish meant that for hundreds of years commercial trawling was relatively limited, with only salted fish being traded in large quantities. Fresh fish were much rarer and were only supplied by small-scale local fishermen who could catch fish close to the shore and get it to market the same day.
Sail-powered trawling remained the dominant type of commercial fishing until the late 1800s. The main type of commercial vessel used in Britain was the smack, a type of trawler that often had distinctive red sails due to a coating which was applied to protect the sail from the weather and saltwater. In the USA, particularly around the cod fisheries of New England schooners were the dominant type of fishing boat. These were fast but somewhat unstable sail-powered vessels that would act as a mothership to much smaller boats which were known as dories (4). The dories, which typically had a crew of one or two men, would catch fish with handlines and then return to the schooner to unload their catch. While sail power was dominant during this era it was not the only method used to power fishing boats – Iceland still used fishing boats powered by the crew rowing until the early years of the twentieth century (4).
The amount of marine life in the sea during the pre-industrial era cannot be overstated. In the late 1400s the explored John Cabot sailed from England to Newfoundland in Canada and reported that the sea was so full of cod that they could be caught by simply lowering a weighted basket down from the side of a boat and then rapidly raising it to the surface (7). Throughout the age of sail-powered vessels fishermen described seeing shoals of herring were many miles long, skate of 200lbs were common and the nets of trawlers could become so full of fish they would tear open when pulled out of the water, or become so heavy they would prevent the trawler from moving through the sea (5). North Sea cod and coalfish would average 4 – 5ft (120 – 150cm) in length and fishermen using handlines could each catch hundreds of cod in a single day (4). In the Firth of Clyde fishermen would regularly catch 350 fish on 400 baited hooks (5). North Sea oyster beds were over one hundred miles long (6), and herring fishing boats could catch hundreds of thousands of fish, and would only return to port as they had run out of salt to preserve their catch (1).
After five centuries of sail-powered fishing, attempts were made in the 1800s to ascertain if commercial fishing had any impact on fish stocks. While complaints were often made that overfishing could happen this almost always referred to sheltered inshore areas such as estuaries where the fish stocks could be closely monitored from land, or areas where isolated populations of fish could be seen to be depleted (1). Very few people seriously believed that the vast, deep ocean could be overfished. Eminent scientists of the time, such as T. H. Huxley stated in 1883:
“I believe that it may be affirmed with confidence that, in relation to our present modes of fishing, a number of the most important sea fisheries, such as the cod fishery, the herring fishery, and the mackerel fishery, are inexhaustible. And I base this conviction on two grounds, first, that the multitude of these fishes is so inconceivably great that the number we catch is relatively insignificant: and secondly … the destruction effected by the fishermen cannot sensibly increase the death rate” (7).
Huxley had significant influence on the fishing policies of the time. He was a member of an influential Royal Commission which tried to ascertain levels of fish stocks, with Huxley reporting back that there was little cause for concern as no human actions could possibly result in any meaningful decline in the number of fish in the sea. At the 1883 International Fisheries Exhibition in London which was attended by most of the world’s major fishing nations Huxley said:
“Notwithstanding the enormous and continually increasing quantities of fish caught annually along the coasts of Great Britain, the English fisheries show no signs of exhaustion” (5).
Huxley is often held up as the main proponent of the belief in a limitless sea as his claims neatly encapsulate the thinking of the time. It is, however, important to note that the belief that the fish stocks were so vast and so numerous that human actions simply could not impact them was widespread among policymakers, scientists and the general public in the late 1800s.
Trawling changed in the late 1800s with the advent of steam power. Early steam-powered trawlers were manufactured from wood and still featured sails as a backup means of propulsion, but purely steam-powered vessels made with steel hulls soon became common. These vessels were more expensive to construct and could be expensive to run – Robert Hewett, the builder of some of the first steam trawlers is said to have remarked “the wind is free, coal is not” (8). Despite this steam-powered trawlers soon overtook sail vessels, particularly with European fishermen in the North Sea who pioneered much of the technology which went on to become used across the world. The reason for this is outlined by Mark Kurlansky in his book Cod: A Biography of a Fish that Changed the World:
“In fishing, new technologies usually came first from Europe, where the water had been fished longer and it was harder to catch fish than in North America. Competition for dwindling catches was the greatest incentive, and the North Sea, shared by eight affluent and fiercely competitive fishing nations, was the leading laboratory for innovation” (4).
Steam-powered trawlers were larger and did not need room for sails, meaning they could carry bigger nets and more fish, and they were much less affected by rough seas and bad weather as they did not have to wait for the correct wind conditions to go to sea. Even with the greater construction and running costs an investment in steam-powered trawlers soon paid off through the much greater catches these vessels could provide. By 1890 there was not a single sail-powered trawler left in the major English fishing port of Hull, with the entire fleet now steam-powered (4).
The fishing gear used by these vessels was also advancing at a rapid pace. In 1892 the otter trawl was invented in Scotland. This was a trawl which has rolling metal bobbins on its underside with heavy metal plates keeping it open on either side. Previous trawls could only be used over relatively smooth ground, but the otter trawl could be used over rough and rugged seabeds, opening up new fishing opportunities to fishermen equipped with this type of trawl. The otter trawl soon became the main type of trawl used across Europe, and the majority of modern trawls used today are still based on a broadly similar design (4).
The increased amounts of fish that could be caught by steam-powered vessels fitted with otter trawls soon became apparent. These vessels reported catches six times greater than traditional sail vessels (6). These increasing catch levels needed a new market to sell to, and this was found by using the growing network of railways which were being built around Britain at this time. Catches could be unloaded at ports and then transferred to railways packed in ice, allowing towns and cities far inland to be supplied with a reliable supply of fresh fish for the first time (4). The species Dover sole is so-called as it was caught in and around Dover and then rapidly transported by rail to London where there was a growing demand for this species.
Historians such as Ingo Heidbrink have found that concern over declining fish stocks was starting to become more widespread at the turn of the twentieth century (9) as the first signs that the sea may in fact be exhaustible were starting to emerge. In the early decades of the twentieth century commercial fishing technology continued to improve. Vessels were now larger with diesel replacing steam power and a growing number of trawlers were able to produce ice on board to preserve fish. This allowed trawlers to stay out at sea for weeks at a time and still return to port with fresh fish. Heidbrink points out that between the first steam trawlers emerging in the 1880s and the outbreak of the First World War in 1914 it had become apparent that there was a “declining ratio between the ever-increasing fishing capacity and catch results” (9). From 1889 onwards accurate records of fish landings in British ports began to be kept which provided the first verifiable evidence that fish catches were declining despite the ever-increasing fish-catching technology which was becoming available (10).
Further evidence was provided when the First World War led to commercial fishing being severely curtailed between 1914 and 1918. In the years immediately following the war fish stocks had increased and catches were much higher than in the pre-war years, proving that fishing had a clear and direct impact on the number of fish in the sea. This new abundance was not to last with the resumption of commercial fishing, and the increasing power and efficiency of vessels soon seeing catches soon slump back to pre-1914 levels (4).
Technological Advances, and the Signs of Overfishing
In the inter-war years, it became apparent that British fisheries, particular the North Sea, were showing clear signs of overfishing. Landings into English and Welsh ports fell from 193,00 tons a year between 1909 and 1913 to 93,000 tons between 1934 and 1939 (5). This led to the first regulations for many vessels which fished beyond inshore waters including minimum mesh sizes for nets and landing size limits for key commercial species (5), but these changes did little to restore fish stocks.
Just as the First World War had allowed fish stocks to replenish the same happened during the Second World War, with naval blockades and the threat from German U-boats severely restricting commercial fishing. This led to a short-lived post-war bonanza as commercial vessels saw huge catches for relatively little effort, but within years the fish stocks were again reduced back to pre-war levels. It was in the years immediately following the Second World War that commercial fishing technology made further rapid advances. Fishing nets had often been made by hand out of natural fibres such as cotton or hemp which rotted over time, but these were replaced with nets made out of synthetic materials which were fully resistant to degrading, even in the harshest conditions (11). Increasing mechanisation also saw the power block invented in 1953 by the Croatian-American Mario Mario Puratic. This was a type of powered winch that made it much easier to haul nets on board vessels and hugely increased the efficiency of purse seine vessels. This was followed by much more powerful winches and machinery which allowed the size of trawl nets to be constantly increased.
A further development that increased the availability of fish to consumers was freezing. The fast-freezing process had been developed by Clarence Birdseye in 1924 and at around the same time fish filleting factories were being established where fish would be processed into ready-to-cook fillets which could be sold to the consumer instead of whole fish. By the mid-1940s factories could process, fillet and freeze fish which could then be sold to consumers or exported, opening up whole new markets for fishing companies (4), and these markets became increasingly lucrative as home freezers became common around the developed world in the second half of the twentieth century.
In the late 1940s a new type of fishing vessel arrived – the factory ship. These huge vessels incorporated many of the new innovations which had revolutionised fishing such as high-powered diesel engines, new net and trawl technology and the ability to both process and freeze catches on board (4). Often over one hundred metres long, factory trawlers could travel huge distances and stay out at sea for weeks at a time and the fish that they caught could be processed and frozen on board (11). Britain, the USA, the Soviet Union, Poland, Spain and East Germany all developed large distant-water factory fleets during this time, with Britain alone having 168 factory vessels by the 1960s (11). Experiments in using sonar to locate fish began as early as the 1920s, but it was only in the post-Second World War years that it began widespread use in commercial fishing (12). The Japanese company Furuno Industries began selling the world’s first commercial fish-finding sonar in 1948, with a similar device from Norway’s Kongsberg Simrad Corporation soon following (12). Echo locators could also be used to determine the type of seabed which was being fished and identify underwater obstructions which would snag trawl nets. This allowed vessels to trawl in areas that had previously been unfishable, removing areas that had acted as safe havens for fish and allowing fishing companies to increase catches.
The Enduring Belief in the Inexhaustible Sea
Unsurprisingly, the emergence of factory trawlers saw the number of fish caught reach new highs in the 1950s. As Mark Kurlansky writes:
“By the 1950s, a time now thought of as the golden age of long-distance net trawling, cod catches were larger every year off the North Sea, off Iceland, Norway, off all of the banks, in the Gulf of St. Lawrence, and along the New England coast. Most of the world’s commercial catches were increasing” (4).
Huxley’s belief that the number of fish in the sea was effectively limitless lived on. In 1955 the book The Inexhaustible Sea was published in the USA. Callum Roberts writes that the book was “continuously upbeat” and urged greater exploitation of the world’s fish stocks and ends with the line “someday men will learn that in its bounty the sea is inexhaustible” (5). Roberts notes that The Inexhaustible Sea was not the work of “hack journalists” or “ill-informed popular writer[s]” but was written by Francis Minot, the director of the Marine and Fisheries Engineering Research Institute at Woods Hole Oceanographic Institute and Hawthorne Daniel, who was an employee of New York’s Museum of Natural History (5).
The optimism of The Inexhaustible Sea was based on an analysis of catch levels at the time the book was published, and in the ten years between 1945 and 1955 global catches did indeed increase, and continued increasing until the late 1970s (9). Fisheries across the world were producing higher and higher catches, despite the centuries of commercial fishing which preceded the publication of the book. With so much commercial fishing having taken place, and more and more fish still being caught Minot and Daniel clearly believed in the claims they made. But they ignored a key factor – catches were only increasing because fishermen were working harder, fishing further afield and using ever more efficient fish-catching technology. As Mark Kurlansky states:
“It was difficult to think of overfishing when the catches were getting bigger every year, but the catches were improving not because the stocks were plentiful, but because fishing was getting more efficient. Nevertheless, as long as better fishing technology yielded bigger catches, it didn’t seem that the stocks were being depleted” (4).
By the mid-1960s fishing technology had advanced to such an extent that seabeds in the deepest parts of the ocean – between 1,000 metres (3,280 ft) and 3,000 metres (9,840 ft) could be trawled. The vessels which carried out this type of fishing were adaptations of existing distant-water trawlers with upgraded winches and stronger and longer cables. Net designs were also changed to incorporate steel and rubber rollers called rock hoppers which allowed the gear to bounce over rocks and obstructions without becoming snagged (5). With the advent of deep-sea fishing almost any area of seabed anywhere in the world could be trawled.
Deep-sea trawling is very different from any other form of trawling. In the cold, entirely dark depths of the deep-sea fish are long-lived and very slow-growing. Orange roughy, for example, is estimated to live for up to 150 years and do not reproduce until they are around thirty years old (7), although some commercial fishermen dispute this and claim the species matures much earlier (7). Other deep-sea species such as roundnose grenadier can live for seventy-five years and need to be around ten before they can reproduce, and leafscale gulper sharks can live to seventy. All of these species are much less fecund than shallower water fish. The orange roughy, for example, lays tens of thousands of eggs, compared to the millions laid by cod (7). The habitat in which deep-sea fish live is also immensely fragile. Seamounts (underwater mountains which can be hundreds of metres high) are home to many creatures and deep-sea corals can be thousands of years old (13). It is estimated that many deep-sea coral reefs were established during the last ice age, meaning that they have been present for between 25,000 and 100,000 years.
While any area of seabed is damaged by trawling, the deep-sea is particularly vulnerable to trawling. Deep-sea fish species simply cannot spawn fast enough to replace the numbers being caught, meaning that entire populations can be fished out in a matter of years. By the early 2000s deep-water trawling of the North Atlantic reduced the populations of fish there to 20 per cent of 1970s levels (7). Britain’s own deep-water fisheries consist of the Rockall Trough to the west of the British Isles and the Faroe-Shetland Channel to the north of Scotland. Deep-sea trawling started in these areas in 1991 and catch rates had fallen by seventy-five per cent by 1994 (7). The same is true of deep-sea fish species elsewhere in the world. The Soviet and Japanese fishery for pelagic armourhead fish in the Pacific Ocean saw tens of thousands of tons of fish caught each year before a sudden crash saw 30,000 tons caught in 1976 and just 3,500 in 1977 (4). Similarly, New Zealand’s fishery for orange roughy produced 100,000 tons a year in the 1980s (7), but after scientists warned that the population was far smaller than fishermen claimed quotas have been cut down, with around 9,000 tons being taken in 2015 (14). In the early days of deep-sea fishing many fishermen and fisheries scientists claimed that huge catches were nothing to be concerned about as they believed that deep-sea species could spawn as quickly and in as high numbers as shallower water fish and used this as evidence to continue fishing (5).
The reality is that this is not the case and deep-sea trawling causes immense, and likely permanent, damage to the ecosystems where it takes place. In The Unnatural History of the Sea, Callum Roberts likens deep-sea fishing to mining rather than fishing, as the resources it takes cannot be replenished. He goes on to describe the damage deep-sea fishing causes:
“Bizarre and beautiful fields of glass sponges have been trawled to oblivion … seamounts that once supported lush forests of invertebrates have been stripped to bare rock by a few decades of orange roughy trawling … untrawled seamounts were carpeted with a near-complete cover of corals and other invertebrates. Trawled seamounts were shocking in their sterility: exposed stark vistas of bare rock, crisscrossed with the scars of repeated trawl passes. The damage being wrought by deep-sea trawlers will last for generations, if indeed it can ever be repaired” (4).
Roberts states that it is impossible to fish the deep sea both sustainably and profitably. The vessels which fish the deep sea cost thousands of dollars a day to run and “have to fish at unsustainable rates simply to break even … if stocks were fished at sustainable rates people would go broke” (5).
In the second half of the twentieth century it had become clear that modern fishing vessels were so effective at removing fish from the sea that unregulated commercial fishing would lead to depleted and in some cases collapsed fish stocks. The Huxlian belief of the inexhaustible sea had finally and definitively been proven to be wrong.
One of the first, and most famous, fishing conflicts happened in the late 1950s when the first Cod War between Britain and Iceland began. British fishermen, no longer able to satisfy the demand for cod and other whitefish species from stocks in their own waters, relied on fishing in Icelandic waters. In 1958 Iceland unilaterally increased their exclusive economic zone (the area of the sea they control) from three nautical miles from the Icelandic coastline to twelve (15), pushing the British trawlers out of some of the most productive cod fishing grounds in the world. The British government claimed the move was illegal and conflict erupted when Royal Navy vessels were sent to protect British trawlers and clashed with Icelandic coastguard boats.
Eventually, Britain had to accept the new twelve-mile limit, but two further Cod Wars took place in the 1970s when Iceland increased its exclusive economic zone to fifty and then 200 miles. The latter two cod wars saw some of the most serious incidents take place, such as Royal Navy frigates ramming Icelandic coastguard boats, Icelandic vessels using specially designed devices to sever the nets of British trawlers and live ammunition being fired at British trawlers. Despite the scale of the British response in all three Cod Wars the British government eventually had to accept defeat and Iceland was successful in extending its exclusive economic zone. Click here to read our full article on The Cod Wars.
Further so-called fish wars (although it is more accurate to describe them as disputes) saw Spain and Canada clash over the right to catch turbot in the mid-1990s, and Britain, Norway and the EU have argued with Iceland and the Faroe Islands over mackerel quotas since 2010. French and British shellfish fishermen have also been involved in a dispute over the rights to catch scallops in the English Channel since 2018, with rocks, flares, iron bars and oil being thrown at vessels. At the time of writing [March 2022] the Scallop War is unresolved.
North America provides two examples of once-abundant fisheries which were reduced to a fraction of their former productivity by unregulated overfishing and mismanagement. The Grand Banks off the coast of Newfoundland in Canada are a range of underwater plateaus which are located where the cold Labrador Current meets the warm Gulf Stream. This unique combination has produced one of the most productive fishing grounds in the world with huge numbers of species such as cod, haddock, redfish, flounder, capelin and swordfish, as well as lobster, crab and shellfish. Canada only controlled the waters to three miles from its coastline, meaning that from this point onwards the Grand Banks were an unregulated fishery. By the 1960s factory trawlers were coming from Britain, West Germany, Poland, Spain, France and the Soviet Union, with 800,000 tons of fish being caught each year from the Grand Banks by 1968 (16).
With fish populations in the area being rapidly depleted the Canadian government extended their exclusive economic zone to 200 miles, banishing the foreign trawlers and taking back control of the Grand Banks for themselves. But instead of using this opportunity to restore stocks and fish within sustainable limits, the Canadian government did the opposite. New fishing vessels were commissioned, shore-based processing plants were expanded, and the number of people employed in the Grand Banks fishing industry increased (4). Throughout the 1970s and early to mid-1980s hundreds of thousands of tons of cod were still being caught from the Grand Banks, but by the late 1980s it had become clear that catches were significantly diminished (4). A report was commissioned which suggested that serious reductions in fishing effort were needed to protect remaining stocks, but under pressure from the fishing industry, a quota of 125,000 tons was still permitted in 1988 (4).
In 1992 the reality of the situation could no longer be denied and a moratorium on cod fishing was announced, and then extended indefinitely in 1994. It was estimated that the spawning stock of Grand Banks cod would have been around seven million tons in pre-industrial times but in 1992 it was calculated at 22,000 tons, just 0.3 per cent of the original population. The collapse of the Grand Banks fishery caused huge economic and social upheaval for the people of Newfoundland, with 44,000 people involved in fishing and fish processing being put out of work (7). Our full article on the loss of Grand Banks cod fishery can be read by clicking here.
The story of Georges Bank is similar. Like the Grand Banks, Georges Bank is an underwater plateau and is located off the Gulf of Maine and shared by American and Canadian fishermen. Due to its relatively shallow waters light reaches much of the seabed of Georges Bank, allowing marine vegetation to thrive which in turn attracts a huge range of fish such as cod, haddock, American plaice, redfish, herring and yellowtail flounder, as well as commercially valuable shellfish such as scallops (17). Just as the Grand Banks were unregulated and fished by foreign trawlers, the same happened on Georges Bank, with factory trawlers from all over the world fishing the bank by the 1960s.
In 1976 the American and Canadian governments passed an act that expanded their exclusive economic zone to 200 miles, pushing out the foreign trawlers and allowing the two nations to fish Georges Bank as they saw fit. But just as the Canadian government failed to use this new opportunity to fish the Grand Banks sustainably, the same happened with Georges Bank. The number of American and Canadian boats fishing Georges Bank almost doubled between the late 1970s and early 1980s (5), with low-interest loans and other financial incentives provided by the government to encourage more fishing vessels to be constructed and more people to join the fishing industry (5). As Callum Roberts states “domestic overfishing replaced foreign overfishing” (5).
Throughout the 1980s catches of key commercial species from Georges Bank declined, with only 40,000 tons of yellowtail flounder, cod and haddock being caught in 1989 (5), and by 1994 scientists calculated that cod stocks were only 40 per cent of what they were four years previously (4). Low-value species such as dogfish and small skates were appearing in catches more and more often as the numbers of these species exploded due to the absence of the cod and larger species that once preyed on them (4). Plans were made for no more than 15 per cent of the total stock of fish to be taken each year, and trawlers had the number of days they could spend at sea limited. This provoked an outcry from much of the Georges Bank fishing industry, who would find it impossible to turn a profit if they could only fish for part of the year (4). Many fishermen turned to catching the skate and dogfish which they once threw away or sold for low prices as lobster pot bait, with others seeking financial assistance from the government to convert their vessels to catch mid-water species such as herring which were still present across Georges Bank (4). Today the number of boats fishing Georges Bank continues to decline and the commercial fishing which still takes place is subject to severe restrictions. Read our full article on the decline of the Georges Bank fishery by clicking here.
Both the Grand Banks and Georges Bank fisheries find themselves stuck in an impossible situation. Fish stocks in both areas have been reduced to a fraction of what they once were, but the pressure to allow commercial fishing to continue remains intense. This means that any successful conservation measures which see fish stocks begin to increase are immediately met with loud campaigns from powerful commercial fishing lobby groups to allow fishing to restart. As Mark Kurlansky writes “The problem with the people … out here on the headlands of North America, is that they are on the wrong end of a 1,000-year fishing spree” (4).
The World’s Fish Stocks Today
Despite the collapsed fisheries, growing numbers of factory vessels, ever-improving fisheries technology and more and more fishing boats operating across the world, the total of world fish catches appeared to continue during the twentieth century. In 1950, 40 million tons were reported globally. This rose to 80 million tons in the early 1990s and 95 million tons in 2000 (7). These figures were used by representatives of the commercial fishing industry to justify continual expansion and were reported as accurate by the Food and Agriculture Organisation of the United Nations. This changed when Reg Watson and Daniel Pauly, both renowned scientists at the University of British Columbia in Canada, reanalysed old statistics on fish catches. They found that across most of the world catches had actually been falling but catches in Chinese had been reportedly increasing (18). This had the effect of pushing the total world catch into growth. Pauly and Watson worked out that China had been over-reporting its catches, possibly because its fishermen were under political pressure to show continued expansion of the nation’s fishery sector. If the true figures for China were used then global fisheries catches had peaked in 1988, and had been in decline, not growth, during the 1990s and early 2000s (18).
What is the true state of the world’s fish populations today? In 2019 a study reported by the journal Science found that the number of fishing boats in the world doubled from 1.5 million in 1950 to 3.7 million in 2015. Despite a much higher proportion of these boats having engines and more advanced fish finding and catching technology, it was calculated that modern fishing vessels caught 20 per cent as much fish as 1950s vessels for the same effort (19). But this fails to acknowledge that even by 1950 the world’s fish stocks were significantly degraded compared to the levels they were at in pre-industrial times, and fishermen then would have had to work much harder then than their predecessors to make the same catch levels. As Chris Armstrong states in A Blue New Deal:
“Despite a massive increase in fishing effort, overall catches have gradually declined. Endless sums of money and ever-improving technology are being pushed into an industry which is chasing fewer and fewer fish and gradually destroying its own future” (1).
There can be no doubt that fish stocks across the world have seen serious declines due to the ongoing expansion of commercial fishing and are now at their lowest point in human history. In a 2003 report in the scientific journal Nature, Boris Worm and Ransom A. Myers used a meta-analytic approach that combined data from multiple previous studies and concluded that the global biomass of large predatory fish was at 10 per cent of pre-industrial levels (18). As Charles Clover states in The End of the Line:
“The sea is almost empty of older fish. A plaice gets no older than six nowadays, but, given the chance, can reach the age of forty. A cod, likewise, will rarely reach six years old, but has evolved to live twenty years and more, laying larger, healthier and more numerous eggs when it does so.” (7)
There is also evidence that overfishing is changing the evolution of fish. As smaller fish are more likely to escape fishing nets scientists have found that fish may be adapting to grow more slowly and reach a smaller overall size to increase their chances of avoiding being caught in nets. A 2002 study on Atlantic silversides, a small fish that grows to around six inches (15cm) in length. Around 900 fish were used in the study, which found that when the largest fish were removed from a population the overall size of fish in the group could begin to reduce within just four generations (21).
Despite this, eating fish is still heavily promoted and encouraged. The UK government has actively stated that people should eat more fish saying “the majority of the UK population does not consume enough fish, particularly oily fish, and should be encouraged to increase consumption.” It was recommended that fish should be eaten twice a week, with at least one of these being a portion of oily fish, such as mackerel or herring. It was not until 2016 that this advice was amended. It was still recommended that fish be eaten twice a week, but the government now said that the fish should be sustainably sourced (22).
The global demand for fish and seafood continues to grow, as fish stocks continue to decline. As Charles Clover warns: “Our love affair with fish is unsustainable” (7).
The second part of this article which looks at modern fishing and what can be done to restore fish stocks and allow the marine environment to recover is currently being written and will be uploaded later in 2022.
1. Armstrong, C. (2022), A Blue New Deal: Why We Need a New Politics for the Ocean, Yale.
2. Gutenberg, J. Extensive Trade in Fish between Egypt and Canaan 3,500 Years Ago, Science Daily, October 15, 2018.
3. Pilcher, H. Fish Fossils Reveal Roman Trade Routes, Nature, July 14, 2003.
4. Kurlansky, M. (1997), Cod: A Biography of the Fish that Changed the World, Vintage.
5. Roberts, C. (2007), The Unnatural History of the Sea: The Past and Future of Humanity and Fishing, Gaia.
6. The Inventor of Salt Herring, The New York Times, September 26, 1886.
7. Clover, C. (2004,) The End of the Line: How Overfishing is Changing the World and What We Eat, Ebury Press.
8. The Advent of Steam Trawlers, The Short Blue Fleet, accessed on March 1, 2022.
9. Heidbrink , I. The First World War and the Beginning of Overfishing in the North Sea in Environmental Histories of the First World War (2018), Tucker, P., Keller, T., McNeill, J. R., and Martin, S. (Editors), Cambridge University Press.
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