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<br /> <br />J <br />1 <br />1 <br />1 <br /> <br />1 <br /> <br /> <br />1 <br /> <br /> <br />t <br /> <br /> <br /> <br /> <br />In contrast to the other study areas, habitats used in Lily Park were <br />mainly pools throughout fall and winter months. This was likely due to the <br />large quantity and high quality of pool habitat available. Very little <br />embayment and no backwater habitat was present in the upper portion of the <br />study area where radiotagged fish were located. Pool habitats were <br />exceptional in that they offered diversity of structure and depths. During the <br />spring habitat use was mainly shoreline and eddy. Some backwater habitat was <br />used in the lower portions of the study area, however this habitat type was <br />not accessible on a regular basis due to fluctuating water levels. Pool <br />habitat was used by one squawfish in late June after runoff flows subsided. <br />Apparently this fish did not migrate to the spawning area. <br />Depth utilization over time <br />Depth utilization was analyzed for each biweekly trip and habitat group <br />(Appendix D). Both effective depth (ice-free water under all forms of ice <br />cover) and total depth (water plus ice) were compared to determine the extent <br />of ice cover and better evaluate water surface elevation and discharge <br />requirements. Habitats were grouped into backwater and embayment (BA EM), run <br />and shoreline (RU SH), and eddy and pool (ED PO). in many cases it was <br />difficult to distinguish between the two types in each group in the field, <br />especially under ice and snow. For this reason, they were grouped for <br />analysis. <br />comparison of depths used between years showed that depths used in all <br />habitat categories decreased in Winter 2, which had lower winter flows (Table <br />12). The average mean monthly flow during ice cover in Winter 1 was 396 cfs, <br />fired to 241 cfs in Winter 2. <br />Some effect on depth utilization can be expected from variation in <br />discharge levels between the two years. However, depth utilization was fairly <br />consistent for BA EM and RU SH habitats considering the magnitude of <br />differences in discharge between years. The major differences in discharge <br />between years occurred in the early and latter portions of the winter. <br />Discharges during January through mid-February were on average only 100 cfs <br />higher during winter 1. This difference could translate into as much as a <br />foot difference in water surface elevation. Depth utilization by squawfish <br />did not reflect this potential difference in BA EM and RU SH habitats. The <br />comparatively high difference in depth utilization in ED PO habitats between <br />years could be misleading. Most data gathered during Winter 1 in eddy habitat <br />were from one fish in a deep eddy at RMI 76.2 and includes no pool habitat. <br />During Winter 2, most pool habitat data were from the Lily Park area where <br />fish used a wide variety of depths in pool habitat. Squawfish utilized shallow <br />pools at the head of riffles and a large pool at RMI 53.3, which had a large, <br />centrally located, submerged, sand bar deposit. <br />The bi weekly means of each habitat group from Appendix D were averaged <br />for the winter period with ice cover (Table 12). This approach gives each <br />trip equal weight and reflects depths on average that one would expect <br />squawfi.sh to utilize in each habitat group throughout the period of ice cover <br />for both years combined. Ranges reported in Table 12 are for bi-weekly means, <br />not the overall ranee of depths utilized. Depth utilization was different <br />between habitat types. Shallowest depths used were in embayments and <br />backwaters and deepest depths used were in eddies and pools. Comparison of <br />differences between mean effective and total depths in each category shows <br />41 <br />t