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1 <br />' <br />Step 3. Accounting for population demographics <br />Based on the N. calculated for each species (Table 6) and a 95% certainty that subadult and adult <br />fish (>4-yr old) would not fall below that minimum target, the demographic model developed by <br />Crowl and Bouwes (1998) was used to determine how many adults (N.) were required to maintain <br />each population or subpopulation. The models for each species were initiated with a set number <br />of adults in a particular subpopulation (chosen to maintain a target goal ie. Ng in Table 6). Model <br />simulations were then performed iteratively to determine how many total adults (N.) were <br />required, under the above assumptions for 95 out of 100 simulations not to fall below the cut-off <br />value of Ng. Each simulation represented 120 years. Each time the adult population fell below the <br />target value of Ng, or the population showed a negative trajectory, suggesting an extinction vortex, <br />that particular simulation was scored as a failure. If the adult population did not drop below N. <br />between year 20 to 120, the simulation was scored successful. If fewer than 95 of the 100 <br />simulations were successful then, a higher number of initial adults was entered and the process <br />' began again. Figure 2 represents `typical' simulations for each of the four species using the <br />number of initial adults that ultimately met this criteria. This process was continued until at least 95 <br />of the 100 simulations were successful. An average population size number (N.) was calculated <br />' from the successful simulations for each species (Table 7 and Figure 2). This number (N.) is the <br />target interim management objective for recovery for each species based on current demographic <br />values for all life-stages and genetic maintenance criteria (Table 7). <br />1 <br /> <br /> <br />1 <br /> <br /> <br />1 <br /> <br /> <br />17 <br />1