Pulse Trawling

Pulse trawling (also known as electro trawling and electric pulse trawling) is a technologically advanced – and highly controversial – method of commercial fishing which has only been used on an experimental basis up until now. Attempts to make pulse trawling a mainstream commercial fishing method across Europe’s seas have led pulse trawling to become a major issue in European politics.

Pulse Trawl
A pulse trawl uses electricity to shock fish out of the seabed.

Little research has been carried out into the long-term effects of this type of fishing and there are serious concerns over the impact pulse trawling has on fish stocks and the wider marine environment. Despite huge pressure to allow pulse trawling to expand and become accepted as a mainstream fishing method, it does now appear that this type of fishing will be banned in European waters in the coming years.

Development of Pulse Trawling

Pulse trawling is an adaptation of beam trawling, a method of commercial fishing which has been used for over one hundred years. Beam trawling is used to catch flatfish species which live and feed over soft sandy or muddy seabeds. A net is dragged across the seabed by a trawler and the mouth of the net is held open by a solid metal bar with up to twenty ‘tickler chains’ thrashing the seabed in front of the net. This stirs up fish (especially flatfish and prawns which bury themselves under the sand and silt of the seabed) which then allows the fish to be scooped into the net. Beam trawling is considered one of the most environmentally destructive forms of trawling by environmental groups such as Greenpeace due to the very high levels of bycatch and the damage caused to the seabed by this type of commercial fishing.

Beam Trawl from 1893
Beam trawling has been around for well over a hundred years. This picture shows a beam trawl in action in 1893.

The pulse trawling system was invented in the Netherlands by Piet Jan Verburg in 1992 and is an adaptation of beam trawling. This method of fishing replaces the tickler chains of traditional beam trawling with a series of electrical drag wires. These wires send electrical pulses into the seabed which causes the muscles of fish to contract. This forces the fish upwards out of the seabed and into the net (1). The Dutch fishing industry has been the biggest proponent of pulse trawling and has pushed for restrictions on pulse trawling to be lifted. They claim that pulse gear has less contact with the seabed meaning that there are lower levels of bycatch, less damage to the seabed and fish that are caught are in better condition and therefore reach a higher price at market. Furthermore – and the point that is of most interest to commercial fishermen – is that pulse trawls are up to ten times lighter than traditional beam trawling gear (2), meaning that fishing with pulse gear uses much less fuel than beam trawling. Although it costs around £300,000 to convert a beam trawler to a pulse trawler and retrain the crew to use the new equipment (3), the savings that can be made mean that this investment can soon repay itself.

Pulse Trawling: Supposedly Banned by the EU

It is important to note that despite commercial pulse trawling taking place in European waters this type of fishing is officially banned by the European Union. Article 31 of Council Regulation (EC) No. 850/98 covers unconventional fishing methods and states:

“The catching of marine organisms using methods incorporating the use of explosives, poisonous or stupefying substances or electric current shall be prohibited.” [Emphasis added]

Technically, this makes pulse trawling (or any kind of fishing using electricity) illegal anywhere within the waters of the European Union, although a legal exception exists to allow pulse trawling to be carried out for research purposes.

This loophole has been heavily exploited by the Dutch fishing industry. They have lobbied to allow greater freedom to use pulse and electrical trawling gear for research purposes and in 2010 were partially successful in getting the restrictions on pulse trawling eased – a maximum of 5 per cent of the Dutch commercial fishing fleet was allowed to use electrical fishing gear (3). This may have seemed like a small rise but it meant a quadrupling of the number of vessels fishing with pulse trawls. In 2012, the number of Dutch trawlers allowed to operate pulse trawls was allowed to increase to 10 per cent of the fleet by the EU (3). This meant that there over one hundred fishing vessels – the vast majority from the Netherlands – have been converted into pulse trawlers despite the supposed EU ban on this type of fishing still being in force (2). Some of the conversions to transform fishing boats into pulse trawlers have even been funded by EU money (4). In a statement given to the BBC a spokesperson from the Government of the Netherlands Department of Agriculture said that the “relatively large number of participating vessels” was necessary because “the current assessment aims to investigate the long-term effects of a large scale introduction of pulse fishing in the North Sea ecosystem” (5).

Diagram of a pulse trawl in action.
Diagram of a pulse trawl in action.

Due to the European Union’s Common Fisheries Policy the Dutch fishing vessels which are fitted with pulse trawls are theoretically allowed to fish anywhere within EU waters. This means they can operate up to twelve miles away from the British coastline, although most pulse trawling has been limited by regulations during the ‘research phase’ to an area in the southern North Sea. As the UK government still controls the twelve-mile zone around Britain it has been able to stop pulse trawling from taking place within British inshore waters, but this changed in 2015 when news emerged that twelve UK registered vessels had been equipped with pulse trawls and could therefore fish within the twelve-mile zone which the UK still controls (3). An article in the Guardian stated that at least some of these vessels had been financed by Dutch fishing companies (3).

It is not difficult to see why the Dutch fishing industry is pushing forward with pulse trawling, and why fishermen from other countries may also be keen to adopt the technology. The lighter fishing gear means huge fuel savings with one Dutch fisherman telling the BBC that he went from taking home €30,000 per year to €70,000 after equipping his fishing boat with pulse trawl equipment (5).

The Impact of Pulse Trawling

With the EU allowing – and in some cases funding – the expansion of pulse trawling many people would assume that it has been fully tested and proven to be a safe and low-impact method of fishing, but this is not the case. Many commercial fishermen, environmental campaigners and marine scientists point to the lack of research into the impact of this type of fishing. Commercial fishermen working out of ports in Kent and Essex reported that they were catching unusually high numbers of dead Dover sole and other flatfish in their nets in 2012 after Dutch pulse trawlers started operating in the area. A Sunday Times article reported on this, with the fishermen interviewed placing the blame squarely on the Dutch pulse trawling fleet (6):

[It’s like] “Fishing in a graveyard…What they don’t catch they annihilate … virtually everything is dead.”

Tom Brown, Secretary of Thanet Fisherman Association.

“This is absolutely devastating for us because we never caught so many fish that [were] already dead … it’s a waste of time going to that area now. It stinks of dead fish.”

Jeff Loveland, owner of two fishing boats operating out of Ramsgate, Kent.

“I have fished there for 30 years and never seen anything like it. I think the pulse is killing the food in the seabed. Three years ago I caught 40 tons of sole in those grounds in one year. It was the best year we’ve ever had. There is nothing there now that I can catch.”

Roger Free, commercial fisherman from West Mersea, Essex.

There are also serious concerns that the spawning grounds of Dover sole could be exploited by pulse trawling. This species moves to the southern North Sea to spawn. These spawning grounds are mostly inaccessible to traditional heavy beam trawls but could be accessed by the much lighter pulse trawls which can work across very soft ground. Dutch pulse trawlers who have a quota to catch sole were allowed to fish in this area during the spawning season (2).

Flatfish Buried in Seabed
Flatfish which bury themselves in the seabed are the main target of pulse trawlers.

The Low Impact Fishers of Europe (LIFE) a campaign group which represents small-scale fishermen working across Europe are also seriously concerned about pulse trawling, pointing out that very little serious research has been carried out into the long-term effects of fishing with electrical pulses, or the impact that it has on marine organisms which live in the seabed. They point out that there is little way of regulating the power of the electricity which is used or the frequency of the pulses which are emitted by the fishing gear (4). ICES (International Council for the Exploration of the Sea), the world-leading marine science organisation, states that pulse trawling could be a benign, ecological option for commercial fishing, but agrees that further research is needed to answer the “unresolved questions” over the impact that this type of fishing has on the marine environment (7).

The prominent environmentalist George Monbiot has been a long-standing critic of pulse trawling. In 2015 he wrote an article in the Guardian entitled We Should be Outraged by Europe Slaughtering Sea Life in the Name of ‘Science’ and expanded on his views on pulse trawling in an interview for the BBC’s Newsnight programme in 2017. Monbiot is critical of the repeated claim that pulse trawling is less damaging than traditional beam trawling, not because it is untrue but because “beam trawling is so fantastically damaging to the seabed” that it is very easy to create a commercial fishing method which causes less damage (5).

An article published in the Independent in 2016 compared pulse trawling to fracking – the fracturing of underground rocks with high-pressure water to release the gas they contain. Both are supposedly clean and safe but little research has been done into the medium and long-term effects (8). In the same article, it was claimed that the damage pulse trawling causes to the small creatures and food sources within the seabed may cause whole areas to become “fished out” if they are subjected to intensive pulse trawling (8).

Further evidence of the destructive potential of pulse trawling can be found outside of Europe. Pulse trawling was used extensively in the East China Sea in the 1990s to catch shrimp. By the year 2000, there were around 10,000 beam trawlers working in the area, around 3,000 of which were equipped with pulse trawling gear (9). Catches of all kinds of shrimp, especially the burrowing species of shrimp, began to increase. However, lack of regulation meant that different levels of power were being used in the pulse gear, and it soon became apparent that damage was being caused to both juvenile shrimp populations and other benthic species (those that live in and on the seabed such as crabs, shellfish and starfish) (9). Pulse trawling was therefore banned in the seas around Zhejiang Province which had previously been the most common area for pulse trawling, and the rest of the East China Sea soon followed (9). Further evidence of the destructive impact of pulse trawling was gathered in 2013 when an article published in the peer-reviewed academic journal Fish and Fisheries found that pulse trawling had a serious impact on fish eggs and embryos in a freshwater environment (6).

Indeed, it is the lack of long-term research which is one of the most worrying aspects of pulse trawling and the knowledge gaps which still exist in the impact that this form of fishing has on the marine environment. In his BBC interview George Monbiot pointed out that the Dutch pulse trawling was more like a commercial fishing operation than scientific research as there was “no control area, no methodology, no way of assessing the results of this experiment” (5).

One serious impact of pulse trawling which has been verified by peer-reviewed scientific research is that large gadoid fishes (cod and related species such as haddock and whiting) which come close to pulse trawl gear can suffer from haemorrhages and muscular contractions which cause breakages of the spine (10). Tammo Bult, Director of the Wageningen Marine Research told the BBC that species such as shellfish, flatfish and sharks and rays did not appear to be affected by pulse trawling, but large cod which come to near to the pulse trawl gear can “have breakage of the spine … in that size of cod their own muscles break the spine” (5).

MSC Logo
The Dutch pulse trawl fishery only narrowly missed out on MSC certification.

Despite these concerns, the Dutch plaice and sole fishery in the North Sea which uses pulse trawling was put forward for certification as a sustainable fishery by the MSC (Marine Stewardship Council) in 2016. There are three criteria assessed for MSC certification: healthy stocks, minimum ecosystem impact and effective management. A score of over 80 points must be reached in all three categories to be awarded certification. The fishery reached this in the healthy stocks and effective management category, but only scored 77 for minimum ecosystem impact, and was therefore not awarded the MSC certification (11). Many conservationists, scientists and other groups who are opposed to pulse trawling were concerned that a fishery based around pulse trawling came so close to being able to refer to itself as an officially sustainable fishery.

Push for Pulse Trawling to Become a Mainstream Fishing Method

In July 2017 it was reported that pulse trawling was set to “get the green light” after a special meeting at the EU parliament, with the European Commission and the Dutch fishing industry pushing for regulations limiting pulse trawling to be lifted. Elisa Roller, the Head of Unit at Directorate General Maritime and Fisheries Affairs of the European Commission was quoted as saying that pulse trawling was the “the most innovative, most researched and most fuel-efficient” (2) and was satisfied that enough research and testing had been carried out to make pulse trawling a mainstream fishing method throughout European Union waters (2).

Sole
No one knows what the long-term impact of pulse trawling will be on species such as sole and the creatures they feed on.

Many anglers, commercial fishermen, scientists and marine conservationists were deeply concerned to hear that the European Commission had taken so little notice of the many voices speaking out against pulse trawling and seemed determined to expand this form of fishing across Europe. However, the European Commission had to get the legislation allowing the expansion of pulse trawling through a vote by the European Parliament Fisheries Committee and then a vote by MEPs in the European Parliament.

In November 2017 the European Parliament Fisheries Committee voted in favour of expanding pulse trawling and re-classifying it as a conventional fishing method (13). A number of campaign groups joined together to attempt to get the European Commission to stop pushing forward with the expansion of pulse trawling (14) but were unsuccessful, and only the vote by MEPs in the European Parliament stood in the way of pulse trawling becoming a widespread fishing method in European waters.

MEPs Vote to Ban Pulse Trawling

On 16th January 2018 the European Parliament – the only directly elected institution of the European Union – voted by 402 to 232 votes (with 40 abstentions) to ban electric pulse trawling in European waters (15), defying the European Commission which backed the Dutch fishing industry’s plans to expand pulse trawling. The BBC reported there were “cheers and applause” in the European Parliament when the result of the vote was announced (16). Dutch fishermen will be able to continue existing pulse trawling until the ban comes into force.

European Parliament
The European Parliament in Strasbourg where MEPs voted to defy the European Commission and ban pulse trawling.

This was seen as a major surprise by many, as the amount of enthusiasm and political capital the European Commission had expended on pushing forward pulse trawling led many to believe that MEPs would vote in favour of allowing pulse trawling to be classed as a conventional fishing method. Representatives of the Dutch fishing industry were left shocked (17), with fishermen who had invested hundreds of thousands of euros in equipping their vessels with pulse fishing gear being left in a very uncertain situation.

The fact that pulse trawling is still a serious and contentious issue across Europe was underlined in October 2018 when it was revealed that Dutch pulse trawlers were operating in the Dogger Bank, an area of the North Sea which covers British, Dutch and German territorial waters. This provoked outrage as the EU has designated the Dogger Bank as a Special Area of Conservation under its own Habitats Directive. Marine conservation charities such as the UK’s Blue Marine Foundation and France’s BLOOM believe that pulse trawling in the Dogger Bank is illegal and have filed a formal complaint to the European Commission (18).

The End of Pulse Trawling?

Following the MEPs voting in 2018 to ban pulse trawling support for the Dutch fishing industry to continue to develop pulse trawling has ebbed away. In February 2019 the European Parliament and EU member states reached a new agreement on fishing and conservation measures which confirmed a ban on pulse trawling within the EU waters from mid-2021 (19). This date was chosen to allow fishermen who had invested in pulse trawling gear to adapt and change back to other forms of commercial fishing. At the same time, the UK also announced that following Brexit EU vessels would be banned from operating in EU waters if they used pulse trawling technology. George Eustice MP, then the Fisheries Minister, stated that there were “serious concerns about pulse fishing” and it was “wrong that the EU has allowed it to happen” (20).

Dutch MEP Annie Schreijer Pierik
Dutch MEPs Annie Schreijer Pierik (pictured), Peter van Dalen and Jan Huitema made a last-ditch attempt to prevent pulse trawling from being banned.

The Dutch government has resorted to increasingly desperate measures to try and regain support for pulse trawling. In April 2019 three Dutch MEPs launched a last-minute appeal to try to prevent the pulse trawling ban from being officially approved by the European Parliament. This included hanging a pulse trawl net from a crane on the back of a lorry outside of the European Parliament while the Dutch folk singer Geke van der Sloot sang a specially written song entitled Lied Voor de Vissers.  This translates as Song for the Fishermen and the website euractiv.com reported that the lyrics said that “jealousy” was the reason for the pulse trawl ban, as Dutch fishermen are the best in the world (21).

Despite the protest, the ban on pulse trawling in EU waters was officially approved by the European Parliament. Estimates state that the cost of banning pulse trawling could cost the dutch fishing industry as much as €200 million (£173 million) and cost hundreds of jobs (22). There have also been calls for the EU Commission to be investigated with many environmental groups such as BLOOM asking why the Commission pushed so hard to expand and fund a type of fishing when the EU’s own legislation clearly banned such fishing practices and so little is known about the long-term environmental impacts of fishing with electricity (23). In 2019 research carried out by Cefas (Centre for Environment, Fisheries and Aquaculture Science) appeared to confirm that pulse trawling had a significant impact on the health of the marine environment. Research trawls found that there were fewer fish found in areas which had been subjected to pulse trawls with numbers of thornback rays and sole being 2.6 times lower, although the study acknowledged that previous beam trawling may have impacted these numbers (24).

Professor Daniel Pauly, the world-renowned fisheries scientist is a prominent critic of the way that the EU has managed its fisheries. He spoke about pulse trawling at a conference in London in January 2017 saying:

“Trawling is very destructive gear, pulling everything in and destroying habitat and so on . . . But you can make things worse. You can add insult to injury by electrifying this thing. So the animals that would slip under the net get a spasm of electricity. They jump up and they are caught. So you can add to the things that you catch: the last worm, the last little shrimp in the sea. That is literally scraping the bottom of the sea” (12).

References:

  1. Project Pulsefishing – pulsefishing.eu
  2. Pulse Trawling Set to Get Green Light – Fishing News, 11th July 2017
  3. We Should be Outraged by Europe Slaughtering Sea Life in the Name of ‘Science’ – The Guardian, 9th February 2015
  4. Shocking the Fish – LIFE Platform
  5. Pulse Trawling – BBC Newsnight – 5th August 2017
  6. Zapped: Britain’s Fishing Graveyard – The Sunday Times, 24th June 2012
  7. Advice Released on the Effects of Pulse Trawling – ICES.dk, 4th February 2016
  8. Nature Studies: Pulse Fishing is the ‘Marine Equivalent of Fracking’ – The Independent, 14th March 2016
  9. Yu, C., Chen, Z., Chen, L., and He, P. (2007) The Rise and Fall of Electrical Shrimp Beam Trawling in the East China Sea: Technology, Fishery, and Conservation Implications. – ICES Journal of Marine Science, Volume 64, Issue 8, 1st November 2007.
  10. de Haan, J., Fosseidengen, J.E., Fjelldal, P. G., Burggraaf, D., Rijnsdorp, A. D. (2016) Pulse Trawl Fishing: Characteristics of the Electrical Stimulation and the effect on Behaviour and Injuries of Atlantic Cod (Gadus morhua). – ICES Journal of Marine Science, Volume 73, Issue 6, 1st June 2016.
  11. CVO Pulse Sole & Plaice, Marine Stewardship Council.
  12. The Wit and Wisdom of Daniel Pauly and Dirk Zeller, Transcript of a Press Briefing at the Science Media Centre, London – Blue Marine Foundation, 18th January 2017.
  13. ‘The Marine Equivalent of Fracking’: Europe to Legalise Controversial Pulse Fishing – TheJournal.ie, 26th November 2017.
  14. Calls for EU to Reinstate Ban on ‘Destructive’ Electric Pulse Fishing – The Guardian, 8th January 2018.
  15. EU Parliament Calls for Ban on Electric Pulse Fishing – phys.org, 16th January 2018.
  16. Pulse fishing: MEPs vote for ban on controversial method – BBC News, 16th January 2018.
  17. Dutch shocked by call to ban EU electric pulse fishing – Yahoo News, 20th January 2018.
  18. Dutch devastate marine life with electric shock fishing – The Times, 1st October 2018.
  19. EU approves ban on electric pulse fishing from 2021 – Euractiv.com, 14th February, 2019.
  20. EU vessels prevented from electric shock fishing post Brexit – Gov.uk, 13th February 2019.
  21. MEPs confirm electric fishing ban, despite eleventh-hour Dutch effort – Euractiv.com, 18th April, 2019.
  22. Dutch trawler industry furious as Brussels votes to ban pulse fishing – DutchNews.nl, 14th February 2019.
  23. EU Ombudsman urged to probe Commission support of pulse fishing – The Parliament Magazine, 7th November 2018.
  24. A Study to Investigate the Potential Ecological Impacts of Pulse Trawling – Cefas, 20th June, 2019.

Note: This article was originally published in 2012 and was extensively rewritten in 2017 (and updated in 2018 and 2019) to account for developments which have taken place in pulse trawling. Events which have taken place after this date will not be reflected in the text above.