An MP that uses Martell and Froese (2012) method for estimating MSY to determine the OFL. Since their approach estimates stock trajectories based on catches and a rule for intrinsic rate of increase it also returns depletion. Given their surplus production model predicts K, r and depletion it is straighforward to calculate the OFL based on the Schaefer productivity curve. OFL = dep x (1-dep) x r x K x 2
Usage
SPMSY(x, DLM_data, reps = 100)
Arguments
x
A position in a data-limited methods data object
DLM_data
A data-limited methods data object
reps
The number of samples of the TAC
Details
Requires the assumption that catch is proportional to abundance. Occasionally the rule that limits r and K ranges does not allow r-K pairs to be found that lead to the depletion inferred by the catch trajectories. In this case this method widens the search.
References
Martell, S. and Froese, R. 2012. A simple method for estimating MSY from catch and resilience. Fish and Fisheries. DOI: 10.1111/j.1467-2979.2012.00485.x