What does overfishing mean?
Most of us think of a fisherman as a guy in rubber pants and rubber boots holding a fishing rod and a net to catch fish he either eats himself or sells to make a living. The fisherman of our imagination knows when and how to hunt for specific species and respects the oceans so that his catch will be guaranteed for many years to come.
Modern fishing has nothing to do with this ideal. High-tech vessels as big as football fields stay out on the ocean for months, fishing, processing, and freezing fish on board. They use miles-long lines, huge nets that trawl along the ocean floors, and explosives to catch large amounts of fish in a very short time. These fishing fleets are so big, one can even see them from space.
With all the fishing equipment that exists on Earth we could fish on four Earth-like planets. But we only have one Earth and only five oceans, which will eventually be empty if humans continue to fish as much as they currently do, because our modern fishing methods destroy the marine ecosystem. Only a tenth of what is caught is eaten by humans or their pets. The rest consists of fish waste and by-catch, such as other fish species, turtles or dolphins that are accidentally caught and killed. For example, for each pound of shrimp caught, about thirteen pounds of other animals are killed and thrown back in the water.
Overfishing means humans catch so many fish in such a short time that nature can’t keep up. Ninety percent of the world’s large predatory fish like tuna and shark have already been killed. And you know that when pieces in a food web are missing, the whole system is threatened to collapse.
In marine parks fish – especially large predators like sharks and tunas — can breed and thrive. High-tech, satellite monitoring is clamping down on illegal fishing. Sustainable aqua farms are built where fish are raised and caught in specific areas. And marine parks create awareness for the dangers of destroying our ecosystems. Healthy oceans make all humans better off — not just fishermen.
What you can do:
Make sure the seafood you eat is caught in a sustainable way by checking fish shopping guides. Spread the word about the overfishing problem among your friends and classmates. Support organizations such as Pristine Seas that help create marine parks.
By Constanze Niedermaier (Whyzz writer), from "33 Things to talk to kids about global challenges".