LAB ASSIGNMENT: ESTIMATING POPULATION SIZE

OBJECTIVE:To estimate population sizes and dynamics, you will be able to:

1. Compare and contrastmethods of estimating population size.
2. Explain and usesimple mathematical models of population dynamics.
3. Synthesize your research with the primary literature in ecology.

Questions to answer(due next Friday)

1. Provide your data as tables, including the raw data, calculated estimate of population size, and upper and lower 95% confidence intervals. Also report your results in a single figure for all estimates (bar chart with 95% confidence intervals for all estimates, i.e. your group data and the entire class data for each of the two methods of estimating population size).

2. Why are indices not useful for estimating population sizes, but only for relative comparisons?

3. Evaluate your estimated population sizes in comparison to the actual population size. Which method of estimation was more accurate? What assumptions, if any, were violated for each method? How could you improve your estimate?

4. Why do ecologists estimate population size? When would an ecologist want to use a density estimate versus a mark-recapture estimate? (Think about organisms, habitats, types of questions...)

5. What would happen to your density estimate if:

a. the area observed was 50% smaller?
b. some individuals (e.g., females) were harder to detect?
c. individuals were attracted to sampling areas?
d. sampling areas were not randomly located?

Provide mathematical explanations for why each would occur, making sure to think about both estimates and confidence intervals.

Attachment:- Lab-Populations.rar