Your “catch of the day” causes plumes and marine devastation at a much larger scale than any deep-sea mining activity will cause anytime soon

In the fourteenth century, British fishermen from Essex sent a pe­tition to King Edward III from England. They wanted him to ban a new type of fishing gear that some people were dragging along the sea­floor. It was so heavy, they claimed, that it destroyed the seafloor and caused a by-catch of all sorts of un­wanted fish and other animals.

The King promised to investigate the matter, but there is no record of what happens next, says the voiceover at the start of the video about the effects of bottom trawling. Seven hun­dred years later, thousands of fishing vessels routinely trawl the sea floors of the world’s continental shelves, at increasingly larger depths, to feed a growing population. The letter to King Edward III did not create that much of a stir apparently.

A paper published by Ricardo Am­oroso and his many co-authors in 2018 provides some statistics on the matter. Based on high-resolution satellite ves­sel monitoring systems and logbook data on 24 continental shelves, the team estimates that an area the size of more than 1 million km², similar to the size of a country like Egypt, is routinely trawled. And European countries are the worst offenders, with more than 50 % of the seafloor affect­ed compared to much less in other parts of the world.

Testament to the omnipresent na­ture of trawlers is this sentence in a thesis that was recently published by a PhD student in the Netherlands. Dur­ing experiments to monitor plumes caused by a scaled mining vehicle, she writes: “Even though plume monitor­ing suffered interference from bottom trawling activities in neighbouring ar­eas…” Isn’t it telling that you cannot run an experiment on one of Europe’s shelves without experiencing interfer­ence from trawling nearby?

Am I saying that we should just go ahead with deep-sea mining without any concern around habitat destruc­tion? No. But I do feel it is irrational to prevent deep-sea mining from tak­ing place given the sheer scale of sea­bed disturbance that is already hap­pening around the world’s continental shelves – repeatedly. It is odd to allow that to happen whilst preventing a new sector from trialling methods that will ultimately help power the energy transition.