The rest of this article is structured as follows: First, each of the four basic forces of stock dynamics (eqn [1]) is considered in turn. Then, models that include various combinations of those forces are described, starting with relatively simple models, and progressing to more detailed ones. Finally, we discuss extensions of conventional models. Selected content reflects a decided emphasis on marine systems.

Table 1 Common biological reference points (BRPs) and typical applications as target (TRP) or limit (LRP) | ||

BRP |
Description |
Application |

Mortality-based biological reference points | ||

FMSY |
Fishing mortality rate (F) at maximum sustainable yield |
LRP |

X%FMSY |
F equal to X% of FMSY; X<100 |
TRP |

Fcrash |
F giving stock extinction |
LRP |

Fmbp |
F at maximum biological production |
TRP |

Fmax |
F giving maximum yield per recruit (YPR) |
LRP |

F0.1 |
F where slope of YPR curve is 10% that at the origin |
TRP |

FX% |
F giving X% of spawning biomass per recruit at F=0 |
LRP |

Flow |
F giving >50% of years with stock replacement |
TRP |

Fmed |
F giving 50% of years with stock replacement |
LRP |

Fhigh |
F giving <50% of years with stock replacement |
LRP |

Floss |
F giving replacement of lowest observed biomass |
LRP |

Biomass-based biological reference points | ||

bmsy |
Biomass (B) at maximum sustainable yield |
TRP |

x%bmsy |
B equal to X% of BMSY; X> 100 |
TRP |

x%bmsy |
B equal to X% of BMSY; X< 100 |
LRP |

Bloss |
Lowest observed B |
LRP |

Bpa |
B below which expected recruitment is decreased |
LRP |

B50%R |
B at which recruitment is one half its maximum |
LRP |

BX% |
B corresponding to X% of B at F = 0 |
LRP |

Adapted from Collie JS and Glslason H (2001) Biological reference points for fish stocks In a multlspecles context. Canadian Journal of Fisheries and Aquatic Sciences 58: 2167-2176, with permission from NRC Research Press.

Adapted from Collie JS and Glslason H (2001) Biological reference points for fish stocks In a multlspecles context. Canadian Journal of Fisheries and Aquatic Sciences 58: 2167-2176, with permission from NRC Research Press.

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