6. Food Webs - Background

Teacher Background

This is a superb activity if you are planning an ecology based field trip or restoration project in an area where local wildlife can be observed. The student research makes students immensely interested and excited about the organisms they might observe in the field. In many ways, this was the highlight of the ecology unit in my students eyes.

The general idea is that students create a field guide to use in the outdoors. Through the process, students gain experience using published field guides, learn about habitats, food webs, and discover threatened/endangered species in their local environment.

I created my list of organisms with a trip to Point Reyes National Seashore in mind. Thus, the creatures represent riparian and coastal California chaparral habitats. If you are planning a trip, the park you plan to visit will usually have a list of wildlife that you can use. I strongly recommend creating your list of organisms to represent local habitats or habitats you plan to visit. If you have too many students for just consumers, consider increasing the number of organisms by including producers as well.

The concluding activity in which a food web is constructed across the classroom floor is fun but often chaotic. I found that 20-30 students can create a complex, representative food web. Therefore it is recommended that you use one class worth of students to assemble a large food web, put away those organisms and start over with the next group of students. Some organisms, such as top carnivores and decomposers are more rare so you can keep those pages available to add to the following class’s food web if you want.

Crowd control in this activity can be quite a challenge if you have an unruly class. In this case, you may want to consider putting the food web together on the board with students still in their seats.

Student Prerequisites
Knowledge of food chains and organisms’ roles within a food chain.
It is helpful if students know what habitats are and how to use a field guide although this can be taught during the lesson.