All about overfishing

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Overfishing happens when people catch too many fish from the ocean, not leaving enough behind for the population to recover. It occurs when fish are caught faster than they can reproduce and replace themselves. Overfishing can happen with any type of fish, from small fish like sardines to large fish like tuna.

All about overfishing catching salmon cwelmer4 / iStock
The development of industrial fishing technology means that the nets used for trawling can be big enough to swallow a Boeing 747 Jumbo Jet.
Where is overfishing happening?

Overfishing is a global problem, affecting oceans all over the world. Some of the most heavily overfished areas include the Mediterranean Sea, the North Atlantic Ocean, and the coastal waters of Southeast Asia. Many fish species that are popular for food, like cod, salmon, and tuna, are overfished in multiple regions.

Why is overfishing a problem?

Overfishing can lead to the collapse of fish populations, meaning there are so few fish left that the population can’t recover. When fish populations collapse, it can disrupt entire marine ecosystems. Overfishing can also affect the livelihoods of people.

Causes of overfishing

As human populations have grown and fishing technology has advanced, the demand for fish has increased dramatically. Some fishing practices, like bottom trawling and the use of huge nets, can catch large numbers of fish indiscriminately, including young fish and non-target species. Illegal, unreported, and unregulated (IUU) fishing also contributes to overfishing, as it’s difficult to monitor and control.

The global decline of fish populations

The United Nations Food and Agriculture Organization (FAO) estimates that about one-third of the world’s fish stocks are overfished. Some fish populations, like Atlantic cod and bluefin tuna, have declined by over 90% due to overfishing. If overfishing continues at the current rate, it’s estimated that many fish populations could collapse by the middle of this century.

All about overfishing shark bycatch Arrlxx / iStock
Top predators in the ocean such as sharks, sailfish, and tuna are among the most over-fished. An estimated 100-150 million sharks are caught each year, whether by targeted fishing or through bycatch.
Hope for the future

Some solutions include setting catch limits, establishing marine protected areas, and promoting sustainable fishing practices. Consumers can also help by choosing to buy sustainably caught fish and supporting businesses that prioritize sustainable seafood. While overfishing is a serious problem, there is hope for the future. In some areas where strict fishing regulations have been implemented, fish populations have started to recover.


Science / Geography | Ages 7-11

Ocean & Climate

Ocean & Climate | Science & Geography | Ages 7-11 is a KS2 teacher resource. Based on the work of the Convex Seascape Survey, this unit develops students' understanding of climate change, ocean, and sustainability topics.