What Happened to the Patagonian Toothfish?


Through basic mathematical operations, students will gain a deeper understanding of the effects of overfishing on a threatened species, the Patagonian toothfish (also known as the Chilean sea bass).


In the late 1990s, the Patagonian toothfish was designated a threatened species. (A plant or animal species is considered endangered when its population is so low that it needs protective measures to survive. A threatened species is one that is likely to become endangered in the foreseeable future.)

Before the 1990s, few people had heard of the Patagonian toothfish. But in the 1990s, it became a popular dish at restaurants. To make it sound appealing to customers, it was renamed the Chilean sea bass, even though most are not caught near Chile, and it's not even a bass. It reached the height of popularity when Bon Appetit magazine named it the “Dish of the Year” in 2001.

The Patagonian toothfish became so popular during the 1990s that it was getting harder for fishermen to find any. Limits were set, but “pirate” ships rushed in to fill the market demand. According to the U.S. Department of State, this species, while not endangered, is seriously threatened as a result of illegal overfishing. By 2003, some environmental groups were claiming that if this overfishing wasn't stopped, the Patagonian toothfish would become commercially extinct in about five years.

What You Need

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What to Do

  1. Introduce the concept of styles and trends. Then ask students to think of examples of foods that are especially popular. Next, ask them for ideas about why certain foods become popular or trendy. (For instance, a food might be associated with a particular role model or be the focus of a strong advertising campaign.)
  2. Tell students that in the 1990s, restaurants looking for a new product to sell popularized a fish called the Patagonian toothfish. However, restaurants called the fish “Chilean sea bass,” even though the toothfish is not a member of the bass family and most toothfish do not live near Chile. Ask students why they think the restaurants changed the fish's name. (Restaurant owners believed that diners would think “Chilean sea bass” sounded better than “Patagonian toothfish.”)
  3. Tell students that the Patagonian toothfish was a very successful menu item. Ask them what effect they think this popularity might have on the Patagonian toothfish.
  4. Explain to students that the Patagonian toothfish was designated a threatened species because too many fish were caught. (A plant or animal species is considered endangered when its population is so low that it needs protective measures to survive. A threatened species is one that is likely to become endangered in the foreseeable future.)
  5. Tell students that they are going to use math to investigate the effects of overfishing on the Patagonian toothfish. Hand out the Toothfish Math worksheets. Have students complete the worksheets, alone or in groups. Review their results with them. Ask them if they can think of any ways to protect fish like the Patagonian toothfish.


Divide the class into small groups. Instruct each group to agree on one endangered or threatened animal. Tell them to use the Internet or other sources to gather facts about their animals. Then have each group create its own list of math word problems related to these facts. Finally, let the groups share their word problems with one another.

Have each group research the reasons why their animals are either endangered or threatened. Instruct them to prepare and present a written report of their findings.

Teaching Options

Internet Resources

Take a Pass on Chilean Sea Bass
This site is devoted to saving the Chilean sea bass, or Patagonian toothfish, from extinction. It suggests actions people can take to protect this fish, and it offers the Flash Movie “Please Don't Eat Me!”

Endangered Species Program, U.S. Fish & Wildlife Service
This site provides the latest information about which species are endangered in the United States and elsewhere. It also offers a Kids Corner with handy links to additional resources.

Defenders of Wildlife—Kids' Planet
A very useful resource for teachers and students, this site offers a comprehensive list of endangered animals from all around the world, along with invaluable information about each species.

BAGHEERA: In the Wild
At this site, students will find facts and figures about specific endangered animals, from the albatross to the gray whale. They will also learn about the causes of endangerment and about conservation efforts.

EndangeredSpecie.com The Rarest Info Around
Among the many highlights of this kid-friendly site are lists of endangered species by state, a great photo gallery, case studies, and profiles of selected endangered species.