1. Read Chapter 10 in Introductory Fisheries Analyses with R and these notes and consider the items below.
• Define N0, Kt-1, Nt, Ct, ft, q, and Et-1
• What is the equation for the Leslie model? What type of equation is this?
• How is q estimated from the Leslie model?
• How is N0 estimated from the Leslie model?
• Geometrically, how is N0 represented?
• What was Ricker’s suggested modification to the Leslie model?
• What are the six assumptions of the Leslie model?
• Which assumptions are most likely to be violated? Discuss why.
• What is the equation for the DeLury model? What type of equation is this?
• How is q estimated from the FeLury model?
• How is N0 estimated from the DeLury model?
• When should the Leslie model be used in comparison to the DeLury model?
• What R function can be used to fit the Leslie and DeLury methods in R?
• How is the population abundance and catchability estimates extracted from the results of this function.
• How are confidence intervals for the population abundance and catchability estimates extracted from the results of this function.
• What R function is used to perform a K-pass removal estimate?
• How is the population abundance and probability of capture estimates extracted from the results of this function.
• How are confidence intervals for the population abundance and probability of capture estimates extracted from the results of this function.
2. Read Rosenberger’s Box 11.1 in Pope et al. (2010) (the complete chapter is here) and consider the items below.
• What is a primary assumption of the removal method?
• Describe a common behavior of fish that leads to a violation of this assumption?
• What does this particular assumption violation mean for the estimates of abundance and catchability from the removal method?
• What is the author’s argument for how biased results from the removal method could still be useful?
• However, how does the stated findings from the Rosenberger and Dunham (2005) study go against the previous argument?