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<br />Model Description - lacustrine <br /> <br />t <br /> <br />lacustrine habitat suitability was assumed to be determined by the same <br />life requisite components as riverine habitat suitability (Fig. 2). Little <br />information was available to determine how variables combine to determine <br />habi tat sui tabi 1 i ty. We assumed that compensation for one 1 i fe requi site <br />value by another life requisite value occurs except when values for a variable <br />approach levels that have clearly demonstrated negative impacts on growth or <br />survival. <br /> <br />Food component. Average TDS (V1S) is included because the TDS is a <br /> <br />measure of lacustrine productivity. There is a positive correlation between <br />sunfish standing crops and TDS levels, presumably due to the greater amount of <br />food organisms produced at higher TDS levels. <br /> <br />Cover component. Percent bottom cover (V1) <br /> <br />abundance is positively correlated with percent <br />resting areas and protection from predation. <br /> <br />quantifies the amount of cover habitat. <br /> <br />is included because species <br /> <br />cover. Bottom cover provides <br />Percent 1 i ttora 1 area (V 16) <br /> <br />Water qua 1 i ty component. Same exp 1 anat i on as presented in the ri veri ne <br />model description. <br /> <br />Reproduct i on component. Temperature for spawn i ng (V g) descri bes water t <br /> <br />quality conditions that affect embryonic development. Substrate (VlO) is <br /> <br />important in determining spawning success. Reservoir drawdown (V17) is <br /> <br />included because optimal embryo development and survival are dependent on <br />stable water levels during spawning. <br /> <br />Suitability Index (SI) Graphs for Model Variables <br /> <br />This section contains suitability index graphs for the 18 variables <br />described above and equations that quantify assumptions for combining selected <br />variable indices into a species HSI with the component approach. The "R" <br />pertains to riverine habitat variables, and the "L" refers to lacustrine <br />habitat variables. <br /> <br />t <br /> <br />6 <br />