# Demographic FMSY method

`Fdem.Rd`

FMSY is calculated as r/2 where r is calculated from a demographic approach (inc steepness). Coupled with an estimate of current abundance that gives you the OFL.

## Usage

```
Fdem(x, Data, reps = 100, plot = FALSE)
Fdem_CC(x, Data, reps = 100, plot = FALSE, Fmin = 0.005)
Fdem_ML(x, Data, reps = 100, plot = FALSE, Fmin = 0.005)
```

## Arguments

- x
A position in the data object

- Data
A data object

- reps
The number of stochastic samples of the MP recommendation(s)

- plot
Logical. Show the plot?

- Fmin
The minimum fishing mortality rate derived from the catch-curve analysis

## Value

An object of class `Rec-class`

with the `TAC`

slot populated with a numeric vector of length `reps`

## Details

The TAC is calculated as:
$$\textrm{TAC} = F_{\textrm{MSY}} A$$
where *A* is an estimate of current abundance, and \(F_{\textrm{MSY}}\) is estimated
as \(r/2\), where \(r\) is the intrinsic rate of population growth, estimated
from the life-history parameters using the methods of McAllister et al. (2001).

## Functions

`Fdem`

: Current abundance is assumed to be known (i.e`Data@Abun`

)`Fdem_CC`

: Current abundance is estimated from catch curve analysis`Fdem_ML`

: Current abundance is estimated from mean length

## Required Data

See `Data-class`

for information on the `Data`

object

`Fdem`

: Abun, FMSY_M, L50, MaxAge, Mort, steep, vbK, vbLinf, vbt0, wla, wlb

`Fdem_CC`

: CAA, Cat, FMSY_M, L50, MaxAge, Mort, steep, vbK, vbLinf, vbt0, wla, wlb

`Fdem_ML`

: CAL, Cat, FMSY_M, L50, Lbar, Lc, MaxAge, Mort, steep, vbK, vbLinf, vbt0, wla, wlb

## Rendered Equations

See Online Documentation for correctly rendered equations

## References

McAllister, M.K., Pikitch, E.K., and Babcock, E.A. 2001. Using demographic methods to construct Bayesian priors for the intrinsic rate of increase in the Schaefer model and implications for stock rebuilding. Can. J. Fish. Aquat. Sci. 58: 1871-1890.

## Examples

```
Fdem(1, MSEtool::SimulatedData, plot=TRUE)
#> TAC (median)
#> 1302.129
Fdem_CC(1, MSEtool::SimulatedData, plot=TRUE)
#> TAC (median)
#> 2251.832
Fdem_ML(1, MSEtool::SimulatedData, plot=TRUE)
#> TAC (median)
#> 616.2736
```