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<br />. <br /> <br />. <br /> <br />5 <br /> <br />Examples of positive. negative and neutral population responses are shown in <br />Tables 2-4 and Figures 2-4. In the positive example (Table 2. Figure 2), the <br />initial population estimate. 850i220. in years 1998-2000. would be neutral <br />because 850-220=630. which is less than 850. the upper threshold value. and <br />850+220=1070, which is above 350, the lower threshold value. However. in <br />years 2003-05 Pop.-CI ~ 1000 (1300-300). and in years 2008-10 Pop.-CI = 1100 <br />(1400-300). Since these values exceed 850. they express a positive response. <br /> <br />In the negative example (Table 3. Figure 3). the initial population estimate. <br />400i220 indicates a neutral response. because 400+220~620. which is greater <br />than 350. and 400-220=180, which is less than 850, But population estimates <br />for years 2003-05 (220i100) and years 2008-10 (150i100). indicate a negative <br />response. because 220+100=320 and 150+100~250. both of which are less than <br />350. the negative threshold value. <br /> <br />In the neutral example (Table 4, Figure 4). for all years. Pop.+CI is greater <br />than 350 and Pop.-CI is less than 850. Therefore, in this case the response <br />is neither positive nor negative. <br /> <br />Based on a preliminary estimate of the pikeminnow population in 1998 there are <br />735 adults in two reaches. Although it suggests an increase over the baseline <br />population estimate (600i250). this would be considered a neutral response. <br />since it does not exceed 850 (600+250). <br />