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<br />' Conclusions and Recommendations for Future Research <br />' Our level of knowledge about factors that affect recruitment patterns of Colorado <br />t ~ squawfish has been greatly expanded over the last 18 years. The conceptual life-history model <br />represents a summary of this knowledge in a holistic format (Figure 1), It encourages a <br />process-oriented view of Colorado squawfish recruitment and of potential controlling <br />' environmental factors. Unfortunately, our ability to conceptualize and hypothesize about <br />recruitment of Colorado squawfish far exceeds our ability to quantitatively describe this process. <br />' The IBM resented here re resents an attem tat uantitative s nthesis of biotic and <br />P P P q Y <br />' abiotic factors that influence growth and survival of age-0 Colorado squawfish. The model and <br />' its output are intended to be used as a tool to evaluate the relative changes in recruitment that <br />might be observed under different environmental conditions. Emphasis should be placed on the <br />' direction of the predicted change and the prediction should be viewed as a hypothesis to be tested <br />' during the course of future research. For example, red shiner predation was the only source of <br />mortality in our model; mortality from other sources can be expected to act in addition to red <br />' shiner redation. Therefore em hasis should not be laced on the absolute values of model <br />P P P <br />' predictions because the model is a simplification of the natural world and it is unlikely that it will <br />' exactly correspond to events that occur there. <br />The model simulations suggest that predation by red shiners may be a major source of <br />' mortality for larval Colorado squawfish. Our simulations generally assumed relatively benign <br />conditions with low red shiner densities and an environment that greatly reduced the efficiency <br />of red shiner predation (turbid water, alternate prey present). Simulations that used conditions of <br />' clear water or no alternate rey showed that red shiner redation reduced squawfish survival <br />P P <br />' 22 <br />ii <br />