Teacher Information

Target audience

  • Year 10 Biology
  • Year 11 Biology

Class size

  • approximately 28 students. It is suggested students work in teams of three to four.


  • Experiment to operate over a double lesson

Links to SACSA

  • Science 4.5: Investigates and explains the functioning of living systems from the microscopic to the macroscopic.
  • Science 5.5: Interprets and uses information about the structure and function of living systems and their relationship to survival of ecosystems.
  • Science 4.8: Recognises and describes conditions that influence reactions or change in materials.

Learning Outcomes:

At the end of this experiment, students will be expected to understand the:

  • technique of inducing spawning
  • the basics of external fertilisation
  • the difference between male and female gametes
  • the basic elements of experimental design
  • the use of a compound microscope
  • the basics of pacific oyster aquaculture


In these experiments, students will investigate an important aspect of the aquaculture of the pacific oyster, Crassostrea gigas. This oyster species has been farmed in South Australia for over 30 years and is now the second largest industry in the South Australian aquaculture sector.

To determine if oysters are fertile and ready for reproduction, scientists can use a simple experiment that tests to see if the females and males have mature gametes present. This experiment uses thermal shock (rapidly changing the water temperature) to induce spawning in oysters. Oysters are broadcast spawners. This means that they freely disperse their gametes into the water column for external fertilisation. Students will investigate the effect of changing the water temperature on oyster spawning and will also learn about male and female gamete traits.