STUDENT INSTRUCTIONS

Now that you have seen the data in Figure sets 1 and 2, you are ready to address the following question: "Why was elk browsing on cottonwoods and willows so intense during much of the 20^th century in Yellowstone National Park?" Using your hypothesis from the last exercise, can you make predictions about the population dynamics of the elk herds in and around Yellowstone during this time? Were they most likely growing, declining, or relatively constant, and why? Write down your predictions, and then with your partner examine the data presented in Figure 3. Were your predictions upheld, or not? Why?

Be prepared to discuss your impressions and conclusions with the rest of the class.