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Over-Fishing Our Oceans


Many Species of Fish are Endangered Because of Over-Fishing
Over-Fishing Our Oceans

What Causes It

It might be tempting to think that because the ocean is so big, it has an unlimited supply of fish. They do cover ¾ of the Earth's surface and for thousand of years people have gotten food from the sea. We have begun to realize, though, that some ocean animals are disappearing from over-fishing. This happens when fishermen take more fish from an area in the ocean than can be replaced by the new fish eggs being hatched. Fish populations are also being hurt by more ocean pollution.

It's not easy to get fishermen to stop fishing. It is often the job they have always done and may also have been the job done by their fathers and grandfathers. It is hard to break a tradition that has been in a family for generations. It may also be the only job on an island or coastal village. People have to feed their families. Also, no one owns the ocean. It is not like a forest that is owned by a country or person. Anyone in the world can move around on the ocean and fish where they please. For these reasons, it is not easy to get people to stop fishing long enough for fisheries to recover.

How Does It Affect Us

The population levels of fish in different areas in the ocean are kept track of by the U.S. Fisheries Department. The most fish caught by fishermen are the fish that people like to eat -- cod, haddock, and blue finned tuna. These are the fish that have become the most endangered from over-fishing. The U.S. Fisheries department rates populations of fish from abundant to depleted. All three of the most popular food fish and many others are rated as depleted. They have become the most endangered.

What Has Been Done to Fix It

Fisheries experts have suggested many ways to help. They suggest limiting the number of fish that can be caught at any time in one place. They suggest allowing fishing boats to fish only few days per month. They suggest making some parts of the ocean no fishing zones while the fisheries there recover and then rotating which country can fish there at which time of year. They suggest buying out older boats from fishermen so they will retire or move on to other jobs. They suggest making nets with bigger mesh so baby fish can escape and grow up to make more baby fish. They suggest monitoring fishing boat activities by satellite.

Sometimes, countries have agreed to stop fishing if the animals are in danger of going extinct. This worked for several species of whales. Whales used to be hunted by many countries for meat and oil and by the 1940s, some species were so scarce, they were almost extinct. With the development of radar during WWI, it is thought that many whales were killed mistakenly because they looked like submarines on radar. In 1946 the International Whaling Commission (IWC) was formed to study and protect whale herds. Whaling countries like Japan, the U.S., and Norway agreed to follow the rules set out by the IWC. Whale herds have begun to recover, but they will never be what they once where.

Many countries have begun to grow their own ocean fish in saltwater fisheries. This may help ocean fisheries, if it gives them time to recover. To really save ocean fisheries, people will have to fish a lot less and stick to fishing rates that will give fish populations time to recover.

What Can You Do to Help

Try not to eat fish that are considered endangered. You can always check a fish's status on the National Marine Fisheries Service website:

Post Assessment Quiz

(Included in PDF)

Over-Fishing Our Oceans - Read and React

1. Name two reason why fish populations in the ocean have decreased:
2. Name three reasons why fisherman may not want to give up ocean fishing:
3. Name three things governments might help fishermen do to allow fish populations recover:
4. Name a new industry that has developed in the face of our disappearing ocean fish:


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Amsel, Sheri. "Over-Fishing Our Oceans " Exploring Nature Educational Resource ©2005-2020. February 27, 2020

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