Build a food web

Card game: producer, consumer or decomposer

Class size will determine if you are able to use all 34 organisms in the food web card set. If your class is small, you can place cards on chairs or on the floor. Alternatively, you can reduce the number of organisms — but be sure to have a balance or producers, consumers and decomposers or your food web won’t work. If your class is greater than 34, producer cards can be doubled up to ensure everyone can make a connection.

Materials

• Producer, consumer or decomposer cards — must be assembled by printing, gluing to construction card, and cutting out to form a double-sided card for each organism).
• Roll of string (you will need around 20 lengths of approximately 2 to 3m each).
• (Remove the feral animals from the pack for the first round — see Alien invaders for more information)

Stage 1: info cards (prediction and learning)

These cards introduce students to a diversity of species that can live in or rely on wetlands.

1. Divide students into groups of up to six.

2. Take one card from the set and use it to demonstrate. That is, show features that could help decide which category it fits within (producer, consumer or decomposer).

   Prompting questions:

   • What does the animal eat?
   • What eats the plant or animal?

3. Then distribute one card per student. They must not turn the card over until instructed.

4. Using only the picture and name on the front, table groups discuss each animal or plant to predict which category it belongs in.

5. Students then turn over the cards and see if they were correct.

6. Each table shares with the class, explaining diet, habitat or other details that helped them work out their categories.

7. Then have the consumers identify if they are herbivores or carnivores.

Stage 2: build a food web with string (game)

This game demonstrates how plants and animals living in wetlands rely on each other to survive.

NB. You may not be able to make absolutely every connection described below, especially with decomposers, but make as many connections as you practically can.

1. Line the producers up and give each a few lengths of string. The producer remains stationary, like most plants in real life.

2. Ask herbivore (plant) consumers to find their food source and connect to them (they may have more than one) by holding on to the middle of strings from one or more producers. (That is, leaving the ends hanging down.)

3. Once all herbivores are connected, the carnivores join on to the string attached to the animals that they eat.

4. Decomposers then need to connect to any bits of string left. (If string is not long enough you may need to knot on more.)

5. Before concluding, ask if there are any other plants or animals that might not be eaten, but might be important for providing homes to other ones? (As an example, river red gums provide shade for the water in the summer, and drop branches which become safe homes for baby fish).

After the game, conclude by asking: What do you think might happen if one of the plants in the food web suddenly died? What would happen if there were no decomposers?