Length-Based SPR MPs
LBSPR.Rd
The spawning potential ratio (SPR) is estimated using the LBSPR method and compared to a target of 0.4.
Usage
LBSPR(
x,
Data,
reps = 1,
plot = FALSE,
SPRtarg = 0.4,
theta1 = 0.3,
theta2 = 0.05,
maxchange = 0.3,
n = 5,
smoother = TRUE,
R = 0.2
)
LBSPR_MLL(
x,
Data,
reps = 1,
plot = FALSE,
SPRtarg = 0.4,
n = 5,
smoother = TRUE,
R = 0.2
)
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?
- SPRtarg
The target SPR
- theta1
Control parameter for the harvest control rule
- theta2
Control parameter for the harvest control rule
- maxchange
Maximum change in effort
- n
Last number of years to run the model on.
- smoother
Logical. Should the SPR estimates be smoothed?
- R
variance of sampling noise for smoother
Value
An object of class Rec-class
with the TAE slot populated
Details
Effort is modified according to the harvest control rules described in Hordyk et al. (2015b):
Functions
LBSPR_MLL
: Fishing retention-at-length is set equivalent to slightly higher than the maturity curve if SPR < 0.4
Required Data
See Data-class
for information on the Data
object
LBSPR
: CAL, CAL_bins, L50, L95, LHYear, MPeff, Mort, Year, vbK, vbLinf, wlb
Rendered Equations
See Online Documentation for correctly rendered equations
References
Hordyk, A., Ono, K., Valencia, S., Loneragan, N., and Prince J (2015a). A novel length-based empirical estimation method of spawning potential ratio (SPR), and tests of its performance, for small-scale, data-poor fisheries, ICES Journal of Marine Science, 72 (1), 217-231
Hordyk, A. R., Loneragan, N. R., & Prince, J. D. (2015b). An evaluation of an iterative harvest strategy for data-poor fisheries using the length-based spawning potential ratio assessment methodology. Fisheries Research, 171, 20-32. https://doi.org/10.1016/j.fishres.2014.12.018
Examples
LBSPR(1, Data=MSEtool::SimulatedData, plot=TRUE)
#> Effort
#> 0.870804
LBSPR_MLL(1, Data=MSEtool::SimulatedData, plot=FALSE)
#> LR5 LFR
#> 99.65718 104.90229