Lesson 2: Designing Food Webs

A food web is a series of interacting food chains. Food chains show the order in which animals consume food. Food chains and food webs are made up of Producers, Consumers, and Decomposers.

Producers: Plants. Plants pull nutrients from the soil and transform those nutrients into matter which animals, fungi, or bacteria can use.
 
Consumers: Animals or other organisms which consume (eat) something. Consumers eat producers (plants) or other consumers. An animal that eats a plant is a primary (first level) consumer. An animal that eats an animal that eats plants is a secondary (2nd level) consumer
 
Decomposers: Animals, fungi, or other organisms which break down animal or plant matter after it dies. This puts minerals back into the soil for plants to use again.

Using the information above, and the example of a food web below, design your own food web, using at least 10 organisms from the website. There are endless combinations to choose from. Illustrate your food web on a large piece of paper or poster board. Be sure to label each organism correctly. Draw arrows clearly. Arrows should point to the animal that is doing the eating (Note: Some animals can eat each other. For example, an adult Bullfrog may eat a Crayfish, but the Crayfish will eat Bullfrog eggs or young).

Sample Food Web:

   

The example above is a simple food web showing how some consumers eat some producers and other consumers. There is even an earthworm, which is a decomposer, that gets eaten by consumers. In turn, the earthworm eats decaying plant material from the plants.

To make a more challenging food web, label your organisms as "producer," "consumer," or "decomposer," as well as the organisms' species names.

For an even greater challenge, you could label your consumers as "primary consumer," "secondary consumer," and so on. After secondary consumer comes tertiary (3rd level) and quartenary (4th level).

 

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