Instructions

• First, do your reading assignment.
• Next, go through Session 1 on the Internet making rough notes and questions you want answered.
• Then do the exercises making notes of questions you want answered.
• Discuss problems or questions with you instructor in person or by e-mail.
• Make a final draft of your notes for this session in your notebook.
• Send a copy of your notebook covering this session to the instructor if you wish or save it until the end of the course.

Reading

• Berryman, A. A. 1997. Chapter 2 and 3 in Principles of Population Dynamics.
• Andrewartha, H. G. and L. C. Birch. 1984. The meaning of "population". Chapter 8 in The ecological web. University of Chicago Press, Chicago.

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Exercises

1. 758 elk spend 3 months each winter in a 5 hectare feed lot. These elk are known to range over a watershed of 1,230 hectares. What is the absolute size of the population and what is its density?
2. A scientist sampled the white grubs in a 3.4 hectare pasture by taking 200 randomly located 1 decimeter (= 100 square centimeters) soil cores. He counted 7564 white grubs in these samples. Calculate the density of white grubs per square meter of soil, per hectare, and the absolute population in the pasture.
3. The elk population (see above) produced 58 calves in 1990 but only 22 were alive by December 31, 1990. In addition, 37 yearling and older elk died during 1990. What was the per-capita birth and death rate and the net per-capita rate of change R over the year? Is this elk population increasing? Define population change in terms of population density and per-capita birth and death rates.
4. If you have $10,000 in the bank at 10 percent annual interest rate, how much will you have in 10 years if the interest is compounded at the end of each year? What is the relationship between the interest rate I = 0.1 and the population parameters G, R, B and D?
5. Use a spreadsheet such as Excel to simulate the dynamics of a population for 10 years using the exponential growth equation and given that the initial density of the population is 10 individuals, the per-capita rate of change is R = 0.8, and the standard deviation is s = 0 (i.e., no environmental disturbances). Plot the trajectory on both arithmetic and logarithmic scales. Click here for hints on building an Excel model.
6. Repeat the simulation above but this time make the standard deviation 0.2. Plot the trajectory on both arithmetic and logarithmic scales.
7. Compare Andrewartha and Birche's concept of "population" to that developed in the textbook.

Examples of the kind of question that may appear on the next examination are:

1. What is a population?
2. How would you decide on the size of the area in which to study a population of organisms?
3. What is a local population?
4. What is a metapopulation?
5. What is an absolute population?
6. What is population density?
7. What is a population index?
8. What is the 1^st principle of population?
9. What is exponential growth?
10. What is the step-ahead equation for forecasting population change?
11. Define the instantaneous per-capita rate of change in terms of per-capita birth and death rates.
12. What is the difference between the finite and instantaneous per-capita rates of change?
13. What two sub-components make up the total per-capita death rate?
14. What is the difference between a differential and a difference equation?
15. What is sensitive dependence?
16. What are transient dynamics?
17. What is a stochastic simulation?
18. What did you learn from reading the article by Andrewartha and Birch?
19. Discuss the results of the exercises.

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