13.2. The Model
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NP number
Total perch number
Fishwt
Mean perch weight
Total fished number
Total fishable mass
Total seinable number
Total seinable mass
FIGURE 13.5
The "Management period" variable determines how often (in days) the
daily quota is updated in the fishery. If the user would like the managers to
set a daily allowable catch every year , "Management period" should be set
to 365. This determines the temporal resolution of adaptive management,
i.e. how rapidly fishery managers adapt to changes in the fish community.
The two randomness variables, "Max. uncertainty" and "Min. uncertainty"
determine the percentage variance in the fishery and Nile perch controls
and unknowns. The difference between these two user-defined variables
will be the random flux percentage in the model. As a default, both variables are set at 1 so the random flux is O.
13.2.1.4. Nile Perch Module
The model so that it can capture either 1) a small Nile perch population invading a pristine system, or 2) an established Nile perch population of