Food Webs – How did the elimination and return of wolves affect other populations in Yellowstone?

To begin this hands-on, minds-on activity, students view a video about ecosystem changes that resulted when wolves were eliminated from Yellowstone National Park and later returned to Yellowstone. Then, students learn about food chains and food webs, and they construct and analyze a food web for Yellowstone. Finally, students use what they have learned to understand a trophic cascade caused by the elimination of wolves from Yellowstone.

This learning activity provides an introduction to the learning activities, Carbon Cycles and Energy Flow through Ecosystems and the Biosphere and Trophic Pyramids. All three of these activities are included in Food Webs, Energy Flow, Carbon Cycle and Trophic Pyramids, which is intended for classroom instruction.

Download Student Handout: PDF format or Word format

Download Teacher Preparation Notes: PDF format or Word format

The Student Handout is also available as a Google Doc (see first link below) which can be used for distance learning. As explained in the Teacher Preparation Notes, we offer another version of the Student Handout for distance learning; this version does not require that students have a printer at home; it is available as a Word doc, PDF and Google Doc (see attachments and second link below). The Teacher Preparation Notes provide instructional suggestions and background information and explain how this activity is aligned with the Next Generation Science Standards.

Copy Google Doc Student Handout

Copy Google Doc No Printer Required