Modern fishing vessels catch staggering amounts of unwanted fish and other marine life. It’s estimated that anywhere from 8 to 25 percent of the total global catch is discarded, cast overboard either dead or dying. That’s up to 27 million tonnes of fish thrown out each year — the equivalent of 600 fully-laden Titanics. And the victims aren’t just fish. Every year, an estimated 300,000 whales, dolphins and porpoises die entangled in fishing nets, along with thousands of critically-endangered sea turtles.
All modern forms of commercial fishing produce bycatch, but shrimp trawling is by far the most destructive: it is responsible for a third of the world’s bycatch, while producing only 2% of all seafood.
Shrimp (and many deep-sea fish) are caught using a fishing method called bottom trawling, which usually involves dragging a net between two trawl doors weighing several tons each across the ocean bed. This has a destructive impact on seabed communities, particularly on fragile deep water coral – a vital part of the marine ecosystem that scientists are just beginning to understand. The effect of bottom trawling on the seafloor has been compared to forest clear-cutting, and the damage it causes can be seen from space. The UN Secretary General reported in 2006 that 95 percent of damage to seamount ecosystems worldwide is caused by deep sea bottom trawling.
