A simple control rule that allows fishing when the operational control point (OCP) is above some threshold. By default, this function sets the TAC at F = 100% FMSY when spawning depletion > 0.1.
Usage
HCR_escapement(
Assessment,
reps = 1,
OCP_type = "SSB_SSB0",
OCP_threshold = 0.2,
Ftarget_type = "FMSY",
relF_max = 1,
...
)
Arguments
- Assessment
An object of class Assessment with estimates of FMSY or UMSY and vulnerable biomass in terminal year.
- reps
The number of stochastic samples of the TAC recommendation.
- OCP_type
The type of operational control points (OCPs) for the harvest control rule used to determine whether there is fishing. By default, use (
"SSB_SSB0"
for spawning depletion. Other biomass OCPs include"SSB_SSBMSY"
for spawning biomass relative to MSY and"SSB_dSSB0"
, for dynamic depletion (dynamic SSB0 is the historical reconstructed biomass with F = 0). For F-based OCPs, the terminal year fishing mortality relative F01 or Fmax (using yield-per-recruit) or F-SPR% (seeSPR_OCP
argument) can be used.- OCP_threshold
The value of the OCP above which fishing can occur.
- Ftarget_type
The type of F used for the target fishing mortality rate.
- relF_max
The relative value of Ftarget if
OCP > OCP_treshold
.- ...
Miscellaneous arguments.
Details
The catch advice is calculated using the catch equation of the corresponding
assessment. See Assessment@forecast$catch_eq
, a function that returns the catch advice for a specified Ftarget
.
References
Deroba, J.J. and Bence, J.R. 2008. A review of harvest policies: Understanding relative performance of control rules. Fisheries Research 94:210-223.
Examples
# create an MP to run in closed-loop MSE (fishes at FMSY when B/B0 > 0.2)
SP_escapement <- make_MP(SP, HCR_escapement)
# The MP which fishes at 75% of FMSY
SP_escapement75 <- make_MP(SP, HCR_escapement, relF_max = 0.75)
# The MP which fishes at FMSY when BMSY > 0.5
SP_BMSY_escapement <- make_MP(SP, HCR_escapement, OCP_type = "SSB_SSBMSY",
OCP_threshold = 0.5, relF_max = 1)
# \donttest{
myOM <- MSEtool::runMSE(MSEtool::testOM, MPs = c("FMSYref", "SP_escapement", "SP_BMSY_escapement"))
#> ✔ Checking MPs
#> Error: Some MPs are not a functions of class `MP`: SP_escapement, SP_BMSY_escapement
# }