Food pyramid diagram
The game is played in three rounds. As each round is completed, the students should
discuss the changes that have occurred in the simulated ecosystem.
Setting up the game:
The instructions are based on 30 students. The game should be played in an area large
enough to allow free movement. Begin the game with 10 larval fish, 10 native mussels, and
10 larger fish.
Objective of game:
To survive as long as possible.
1. Students put on the name tags; the teacher scatters the game pieces in a large area
so all students have access to the game pieces.
2. At a signal from the teacher, the students scamble to collect as many game pieces as
3. Each species needs a certain amount of dissolved oxygen and zooplankton to survive.
Students determine which species have survived based on the species needs in the following
* These two species will participate later in the game.
4. Species must have at least the required number of the specific game pieces to
survive; survivors remain the same species for the next round. Species that do not have
the required number of game pieces die and become zebra mussels in the next round (by
turning their tag over). Round Two
5. Collect and rescatter the game pieces. Have the students again collect as many game
pieces as possible.
6. Repeat step thee to determine who survived. If many animals other than zebra mussels
survive, repeat round two.
7.At the end of round two, each animal keeps the game pieces they collected in
preparation for round three.
8. Select three students at random to become diving ducks. The diving ducks may
"eat" any surving animals other than zebra mussels by tagging them.
9. The diving ducks and fish take all the game pieces from each animal as it is tagged.
The tagged animal now has been "eaten" and is out of the game.The round
concludes when all game pieces have been collected.
10. Students discuss who has survived and why. Refer to the chart in step three.
11. Students and teachers discuss the game to illustrate the impact of zebra mussels on
the native species. Students should understand the effects of zebra mussels and how they
can destroy an ecosystem and its biodiversity.
Chart the results from the first and second round. Compare the results to see how in
nature the food web interactions are constantly changing, More zebra mussels will reduce
the number of larger fish because the zebra mussels are depleting necessary nutrients and