What actually is overfishing? Overfishing can take place in any body of water such as lakes, rivers, and of course our oceans, and is basically when too many fish are being caught for the ecosystem to manage. This leads to decreases in population sizes to a level where newly bred fish cannot replenish the numbers of those being caught. In addition, the overfishing of one specific species may have an even greater effect on the whole ecosystem by disturbing the fragile balance of the food chain. One example of this is the overfishing of sharks, mainly for their fins, which has changed the paradigm of the whole marine ecosystem.
Fish and chips has forever been a traditional favourite meal in the UK. Cod, in particular the Atlantic cod, is one of the ideal choices of fish within the UK, and its popularity within Europe and North America has creating a huge and unsustainable demand for this particular species of fish. Cod has been a popular fish since the 1950s, and as global demand has increased, technologies and fishing methods have also developed to supply the market. This allows fisherman to trawl larger areas of the sea bed for longer and at greater depths. This has progressively contributed to the current depletion of cod stocks to levels beyond their capability of replenishing. Even with the introduction of fishing laws and regulations, such as the 1992 cod fishing suspension in Canada, current cod stocks have decreased to such a level that research and computational models are in doubt of their capability for natural recovery.
Thailand is the world’s 3rd largest exporter of fish and within 10 years the volume of exported fish has almost doubled. Thailand has a huge fish farming industry, however to feed the farmed fish, breeders are now using the bycatch from commercial fishing, as trawl fishing catches huge quantities of untargeted species. The Gulf of Thailand is now considered as one of the most exploited in the world with some local species now extinct, and others threatened by decreasing population sizes. In the last few decades or so, even with advances in fishing technologies such as sonar, Thai fishing boats are averaging only around 18kg per day, whereas back in the 60s boats they were averaging up to 300kg an hour! This is a huge difference in only 50 years and shows how truly depleted the oceans are becoming. To make matters worse there’s currently a big problem with slavery where migrants, the majority of which are Burmese, are roped in to work on the vessels in poor conditions with little or no wage.
Overfishing and bycatch are affected by many things, one of which being the size of mesh nets. Some nets have such a small mesh that when pulled tight they almost create a solid sheet, therefore scooping up everything they encounter, targeted species or not. These types of nets are more expensive and therefore poorer fisherman using traditional methods to feed their families cannot compete and thus suffer from an unfair disadvantage. These types of nets are also illegal as they remove many developing, juvenile fish, preventing fish populations from regenerating. However, many big fishing vessels would rather pay the legal fines than use alternate methods, as the profit these nets provide far out scales the fines for using the nets in the first place.
The food and agriculture organisation have estimated that 85% of all wild fisheries are over-exploited, resulting in the world’s marine ecosystem being in major decline. Laws and regulations have been put in place regarding quantities of catch net size, fishing areas, quotas; however, these can be very hard to enforce and are proving ineffective as overfishing is still on the increase. It is estimated that almost 30% of our fisheries are now actually obtained illegally.
What can we actually do to help? Firstly cut down how much fish/seafood you eat in your diet. If the demand decreases, then so will the supply, and there will be less need for fisheries. Try replacing fish with other high-protein foods such as chicken or other meats, or alternatively increase your intake of beans, nuts and seeds. Spend time when choosing where to buy you seafood and take into consideration whether it has been sustainably sourced. Join organisations and sign petitions you believe in, some of which will hopefully persuade the governments that they need to take action such as increasing national marine parks. There will be no change without action, and so it is everyone’s responsibility to do what they can to reduce the impact of fishing on a global scale.