The Great Oyster Mystery

Estuary background image with color overlay


In this activity, students read oyster abundance graphs to describe how young oyster abundance in Aransas and Copano Bays responded to short-term environmental changes. Students then access and print monthly average salinity and rainfall data for a two-year period during which oyster abundance in Aransas and Copano Bays declined and then rebounded. Finally students describe and interpret the relationship between several abiotic and biotic conditions in the estuary, including salinity, rainfall, oyster abundance, and the abundance of parasites and predators that attack oysters.

This activity has three parts:

  1. Clues in the Numbers
  2. A Salty Tale of Intrigue
  3. Cracking the Case with Data

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Students should understand that:

  • Environmental conditions, such as salinity, have a direct influence on estuary organisms.
  • Testing hypotheses through scientific investigation helps answer questions about the natural world.
  • Monitoring the responses of estuary organisms to changing environmental conditions helps scientists make predictions about the potential impact of long-term changes, including climate change.

The Great Oyster Mystery: Supporting Resources

Mission Aransas Map

Take a look at the map below, or download the PDF version.

World Estuaries Map