Table 3.
Harvesting parameters
Parameter | Description | Value or range | Unit | Comments on range |
---|---|---|---|---|
Ms | Length at which selectivity equals 50%, as a fraction of the maximum observed length | 0.17–0.43 | – | Chosen to cover approximately the sizes at 25% through 75% maturation probability across the age ranges examined (e.g., Fig. 1D) |
a | Steepness of the size-specific selectivity curve around Ms | 0.5–25 | – | Chosen to cover a range of shapes of the selectivity curve (e.g., Fig. 2) |
bH | Density–dependent component of harvesting | 0.01–0.2 | – | Chosen to cover a range of harvest regimes not resulting in extinctions |
aH | Total allowable catch for Ht=0 | 50 | g | Chosen to minimize the fraction of biomass harvested when bH=0 |
ϕ | Relative importance managers attach to avoiding harvest-induced evolutionary change | 0.1–2 | – | Chosen to cover a range of distinct levels importance attached to avoiding harvest-induced evolutionary change |