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1 <br />1 <br /> <br /> <br />fs3 = 1 if simulating the feeding strategy of predator group 3; else = 0, <br />fs4 = 1 if simulating the feeding strategy of predator group 4; else = 0. <br />Note that when all fs coefficients = 0, the model simulates the feeding strategy of predator <br />group 5. <br />Standard errors for coefficients are: intercept = 0.557, x, = 0.0294, x2 = 0.266, x3 = 0.331, <br />fs, = 0.272, fsZ = 0.239, fs3 = 1.224, and fs4 = 0.360. <br />A goodness-of--fit test did not detect significant lack of fit (p = 0.25) and suggested that <br />the model fit the data reasonably well. Model fit was further assessed by plotting deviance and <br />chi-square residuals as functions of predictor variables and predicted values. No trends in <br />residuals were observed. <br />The attack-rate equation was used in model simulations in the following way to <br />determine the daily number of predator attacks on each larva. For each larva on each day, <br />equation 4 was solved using the size of the larva, conditions of water clarity and alternate prey, <br />and one of the five feeding strategies selected at random. This daily attack rate was then <br />multiplied by predator density (number/m2) to estimate mean total attacks: <br />Mean total attacks =predator density • daily attack rate <br />The actual number of attacks on the larva for that day was determined by randomly drawing a <br />value from a Poisson distribution with a mean equal to mean total attacks. <br />16 <br />(5) <br />