1. Create a conceptual model Assume 3 stages for the toads Juveniles AdultsPre-juveniles

2. A Toad Transition Matrix 0181000 0.020.20 00.010.75 (based on Biek et al. 2002)

3. Sensitivity analysis Sensitivity: changes in popn growth rate with respect to changes in life cycletransitions Change 1 element in matrix at a time Elasticity: sensitivities scaled so that they are proportions- sum to 1.0 (EXCEL DEMO)

4. So what does this tell us? We know that adults, pre-metamorphs, and eggs are all important to population persistence. NOW WHAT?

5. Using sensitivity analysis results The peregrine falcon (Falco peregrinus) Elasticity matrix 00.0040.091 0.0950.0360 00.0910.683

6. Other considerations…. What about variation? demographic environmental

7. Summary Sensitivities and elasticities are rates of change- slopes. They have biological interpretations but must be used carefully They can be very helpful in determining which management actions will be most effective

8. Ungraded Homework 2. Why can’t an elasticity or sensitivity analysis alone be used as the basis for choosing a management strategy? 1. What is the biological interpretation of the matrix element a 34 ?