Industrial fishing does a great deal of damage to the planet’s ecosystems. Its consequences tend to be underestimated by the general public because most of the damage is invisible, occurring beneath the surface of the oceans and often out on the open sea. Many fishing methods, whether they use lines or nets, impact numerous species that are of no interest to fishermen and result in what are described as “involuntary catches.” Sea birds are drowned or strangled while feeding off bait or trying to snatch fish trapped in nets. Hundreds of millions of fish and hundreds of thousands of birds are lost each year, as well as a great many marine mammals (seals, porpoises, dolphins, and sea turtles), though there are no precise global figures.
Trawling is a particularly destructive practice, which consists in dragging weighted nets along the sea bed. It is also the most heavily used fishing method in the world thanks to the increased power of fishing vessels (itself the fruit of government subsidies): trawling is responsible for 50% of global catches and 80% of all catches in the open sea. As they rake over the rocks, trawlers’ nets stir up clouds of sediments and turn the sea bed into a wilderness. Fishing trawlers are like marine bulldozers, plowing half the surface of the world’s continental shelf each year, and no doubt reducing its productivity (although studies are lacking). They are also greedy consumers of fossil fuels.
Everything interconnects in the living world: the disappearance of a single species can destabilize entire ecosystems. The disappearance of fish stocks threatens all the creatures that feed off them— not just mankind, but birds and marine mammals too.
Part of the solution—even though it may not solve all the problems—lies in the creation of an international network of marine parks, where fishing would be banned or subject to severe restrictions. Only 0.7% of the ocean’s surface is protected in this way today. The international target periodically mentioned is 20%, and if this were to be achieved, the damage caused by fishing would be considerably reduced, while still leaving fishermen sufficient space to pursue their activity.