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. 2020 Apr 29;10:7298. doi: 10.1038/s41598-020-64216-9

Table 4.

Modelled management scenarios that yielding a population growth rate of λ ≈ 1 (i.e., a stable population).

Management scenario LJ HJ Yearlings Adults Sum λ
(190) (89) (122) (100) (501)
unselective HMR (%) 30 30 30 30 1.01
No. 57 27 37 30 151
NH1 HMR (%) 40 40 25 25 1.00
No. 76 36 41 25 168
NH2 HMR (%) 0 80 25 25 0.99
No. 0 71 41 25 137
NH3 HMR (%) 100 0 25 25 1.00
No. 190 0 41 25 246
Juveniles (unselectively) HMR (%) 75 75 0 0 0.98
No. 142 67 0 0 209
Light juveniles HMR (%) 100 0 0 0 1.25
No. 190 0 0 0 190
Heavy juveniles HMR (%) 0 100 0 0 1.15
No. 0 89 0 0 89
Yearlings HMR (%) 0 0 80 0 0.97
No. 0 0 98 0 98
Adults HMR (%) 0 0 0 100 0.97
No. 0 0 0 100 100

Harvesting classes are light (LJ) and heavy juveniles (HJ), yearlings and adults. The number of animals within an exemplary population structured according to the stable stage distribution identified under favourable conditions without hunting mortality is given in parenthesis. For each management-scenario the proportion (i.e., the hunting mortality rate, HMR) and the actual numbers of individuals that need to be harvested (No.) to achieve a stable population (i.e., λ ≈ 1) are given as well as the overall sum of individuals over all classes and the exact λ under the respective scenario. The management scenarios light juveniles and heavy juveniles did not result in a stable population even when 100% of the respective individuals were harvested (i.e., λ ≫ 1).