BIO150Y: Saving the Whooping Crane Exercise

Management Simulations

You are now a manager! Experiment with different combinations of management options to boost population growth and reduce the long-term extinction risk for Whooping Cranes. The best strategy will give the largest reduction in pE compared to the baseline, at the lowest cost.


  1. With management, can you reduce pE below baseline estimates?
  2. What is the most cost-effective management strategy?
  3. Which options have the greatest impact? Those that affect birth rate, death rate, or carrying capacity?

Suggested Methods

  • Choose your management options from the pulldown menus. The population parameters (r and K) and the total cost will be automatically adjusted. Your budget is $50 million and you cannot exceed this.
  • Select Run simulation to open up the simulation applet and then run your simulations.
  • Conduct replicates.
  • Use the data tables in your lab manual to record your results. You can download a print-ready version of the worksheet as a PDF file (19 Kb).
  • Based on your results, answer the quiz questions below.

Some Tips

  • Baseline comparison: Transfer the average pE you obtained from your baseline simulations to the first row of your data table.
  • Be methodical: Start by just adjusting factors influencing carrying capacity, K. Then birth rate and death rate separately. Finally, start to use a combined strategy.
  • Actual counts: This gives you the actual population growth, so you can see how you did!


Based on your results, answer these questions.

What type of management option is most cost-effective for the 1941 Whooping Crane population?

How many cranes were there after 60 years of management?

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