What is overfishing? The term overfishing refers to the practice of catching so many fish that the ability of the fish population to sustain itself is in jeopardy. This can result from catching too many parent fish which prevents ample breeding from taking place. It can also result from just catching too many of the species until they are completely gone. Discover some real-world overfishing examples.
The cause of overfishing is largely due to the number of commercial fishing fleets and the methods of fishing that make it impossible for the ocean to sustain the existence of fish in these fishing areas. As a result of commercial overfishing, some species are extinct or approaching extinction. Discover a few real-world examples of overfishing.
- British overfishing of cod in Icelandic waters led to an ensuing argument between the British and the Icelandic that became known as the "Cod War." A ban on foreign fishing within a 100-mile zone has helped cod to breed and exist in greater numbers now, though the population of cod in this area reached an all-time low in 2007. Conservation efforts continue to this day.
- Overfishing of Swordfish became a worldwide problem in the 1980s. While the population of North American swordfish has largely been restored, there is still a crisis in the Mediterranean. There, continual overfishing and a lack of a population management plan have reduced the swordfish population by 70%. Without intervention, the Swordfish population is expected to collapse.
- Overfishing has long been a serious problem with Bluefin tuna, which is harvested from the Atlantic Ocean and the Mediterranean Sea. Overfishing of this species peaked In the 1990s, at which time this slow-to-breed species became endangered. By 2015, the species transitioned from endangered to threatened. By 2017, these fish were no longer considered to be overfished.
- Wild salmon in the U.S., primarily on the West Coast, are seriously overfished. In 2018, the fisheries division of the National Oceanic and Atmospheric Administration (NOAA) identified five types of Pacific salmon that are currently overfished (Juan de Fuca coho, Klamath River fall-run Chinook salmon, Queets coho, Sacramento River fall-run Chinook salmon, Snohomish coho).
- While Chilean sea bass is not considered endangered (as of 2021), overfishing is a serious problem with this type of fish. These fish, which are actually Patagonian toothfish and Antarctic toothfish, take a very long time to reach maturity. Due to high demand and prices, they are being fished at a rate that is causing pressure on a population that is slow to rebuild itself.
- Krill, which are small shrimp, seemed to be in abundance in the ocean. However, several countries have started harvesting large amounts of krill in the last several decades. As a result, the krill population itself is not yet endangered necessarily, but the lives of those who eat it, such as seals, penguins, squid, and fish, may be negatively affected by the harvesting.
- The Bering Sea's king crab population has long been overfished. In 2018, an NOAA Fisheries report indicated that two types of blue crab in U.S. waters in this region are overfished. Blue king crab from the waters around St. Matthew Island was added to the overfished stock list that year, joining Pribilof Island blue king crab, which has been considered overfished since 2002.
- A study completed in 1997 revealed that red snapper was being overfished in the Gulf of Mexico. In the 1980s, NOAA Fisheries and the Gulf Council implemented a rebuilding plan with many regulations, which is still in place. A snapper fishing season was designated with limits placed on the number of licenses, the fish size that could be kept and how many pounds could be caught.
- In 1992 it was found that there were no remaining cod in Newfoundland due to overfishing. A cod fishing moratorium was implemented that lasted until the late 2000s. Sadly, shortly after reopening to cod fishing, the limits were raised too soon and the population quickly suffered a drastic decline. As of 2019, a decision was made to commit to a long-term rebuilding plan.
- Holothurians in the Indo-Pacific have been overfished, particularly sandfish and teatfish. Researchers are seeking to identify data that will allow for a more complete understanding of the overfishing of these species to help make informed recommendations for a recovery and conservation plant.
- Marlin, skate, flounder, and halibut are also fish that have been overfished. This is largely because they, along with many other fish listed above, are in high demand by the seafood industry. The World Wildlife Fund (WWF) indicates that species fished for food could be completely deleted by 2048 if the rate of fishing does not slow.
Some overfishing occurs as a result of bycatch, which is when fishers seeking to lure certain types of fish end up also trapping and capturing other species incidentally.
- Turtles are subject to overfishing as a result of bycatch. They have often been caught in shrimp or tuna nets. Turtle excluder devices can be used to help keep turtles from getting caught in nets. These devices are required on some nets in some areas but are not universally mandated.
- Dolphins have often been victims of accidental overfishing, by becoming bycatch of tuna fishers in large numbers. More recently, dolphins have increased in number after media attention and dolphin-safe stamps were applied to tuna cans of fishers that used sustainable, dolphin-friendly practices.
- All kinds of sharks and rays are in danger of depletion via overfishing as a result of being fished for their meat and skin and through ending up as bycatch by commercial fishers seeking to capture other kinds of marine life. In this class, sawfish are the most significantly impacted. The U.S. population has declined by up to 99%, while the European ones are believed extinct.
The previous overfishing of herring resulted in ill effects on cod because herring are cod's primary prey. In the U.S., as of 2020, herring are no longer considered subject to overfishing due to U.S. regulations that now require sustainable harvesting and population management. This indicates that an important key to solving the problem of overfishing is to stop poor fishing practices and to better monitor exploited populations of fish.
Individuals can help by remaining informed on overfishing and supporting sustainable practices, namely by purchasing fish that have been sourced in a sustainable fashion. When purchasing fish, look for inventory sourced via a fishery that carries the Marine Stewardship Council (MSC) seal. This indicates that the fishing company focuses on sustainable fishing practices and effective fisheries management, along with proactively taking steps to minimize their environmental impact.
Overfishing is a "tragedy of the commons" problem. It is better for each individual person to overfish to benefit himself, but it would be better for all the fisherman collectively if everyone refrained from overfishing to sustain the population. Those who refuse to follow catch and size limits, which exist specifically to help combat overfishing, are causing problems that will ultimately have a negative impact on their own livelihood or recreation, as well as everyone else's, to the detriment of wildlife and the overall environment.
Now that you have reviewed some overfishing examples, spend some time exploring natural ecosystems in biology. From there, learn about keystone species and what happens when they are removed from a habitat.