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Perfect Pearl, The

Classroom Activity


Objective
To consider political, economic, and technological solutions for challenges faced by pearl farmers.

Materials for each team
  • copy of "Pearls of Wisdom" student handout (PDF or HTML)
Procedure
  1. In this program, Japanese and Australian pearl farmers and scientists describe some of the problems they face, and explain how they have responded.

  2. Distribute to students the "Pearls of Wisdom" student handout. As they watch, have students list the problems they observe and any solutions that exist. Explain that after viewing, they will prepare recommendations for solving some of the current problems faced by the pearl farmers.

  3. Ask students to describe all the problems that pearl farmers had or are having. Write the list on the board. Using their "Pearls of Wisdom" activity sheet, have each student or group of students consider all the problems and how they were solved or could be solved. Allow time for students to complete the activity, then have volunteers present their suggestions to the class.

  4. To conclude, have students compare how pearls are extracted with how some other items are extracted from nature, such as precious stones, minerals, ivory, and furs. What do all of these have in common? How are they different? How are they taken from nature? How is the environment affected? What are some factors that create a demand for these items?

Activity Answer

There are several problems described in the program, including the following:

  • very few perfectly round pearls occur naturally

  • Australian oysters are less hearty than Japanese oysters, resulting in a high oyster mortality rate using Japanese farming methods

  • natural pollution in bay (red tide)

  • overcrowding of oysters in bay that restricts tidal movement, resulting in earlier harvesting and fewer high-quality pearls from Japanese farmers

Students will see that some of the problems were solved through technology: A method to culture pearls solved the problem of having to harvest so many oysters to find high-quality pearls, and a variety of techniques developed to farm Australian oysters with less stress solved the high mortality rates.

Other problems were solved through political or business measures: When scientists monitoring water quality detect dangerously high levels of plankton, they notify government authorities who advise farmers to evacuate their oysters; with fewer good-quality Japanese pearls, Japanese pearl dealers have moved more into brokering pearls.

Still other problems remain unsolved: how to cope with overcrowding in Japan's Ago Bay, how to lower mortality rates for Tahitian-farmed oysters, and how to artificially breed oysters in hatcheries to allow small South Pacific island states a chance to enter the industry.

Student recommendations can vary. Some suggestions might include designing new methods to limit overcrowding, such as finding a new waterway that is less crowded or polluted, reducing the number of oysters each season, or limiting new pearl farms from starting. Students might also suggest cleaning the bay to reduce pollution or redesigning oyster nets to allow for greater water circulation. Or, they may propose genetically engineering a strain of oysters to resist harsh environments.

Teacher's Guide
Perfect Pearl, The
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