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21 <br />Ephemeroptera <br />Mayflies were an important component of fish diets. All are benthic <br />in habitat, are important in the drift, and are generally collectors in <br />habit. Immatures were consumed as well as emerging sub-imagos (pre-adults), <br />and adults. Adults were probably fed upon while returning to the water <br />to deposit eggs. <br />Juvenile G. robusta consumed significantly more Ephemeroptera over all <br />strata than did other fish. At Stratum IX, YOY G. robusta consumed <br />significantly more Ephemeroptera than did other fish and at Stratum E, <br />Adult N. lutrensis consumed significantly more than others. <br />Hemiptera <br />True bugs were represented by Corixidae (boatmen) and Veliidae <br />(broad-shouldered striders). The former arefound in the water column and <br />rest on the stream bottom while the latter are surface striders (neuston); <br />both are predators on other invertebrates. They were a minor food item <br />eaten by only three species, Adult N. lutrensis, YOY Pimephales, and <br />YOY Ictalurus. <br />YOY Ictalurus consumed significantly more Hemiptera over all strata and <br />at Stratum A than did other fish. <br />Nematoda <br />Round worms were found only in G. robusta. Some nematodes are <br />free living on the stream bottom but others are parasitic on a large <br />number of organisms. Those in G. robusta were approximately 2 mm long <br />and were in the interstitial convolutions of the stomach. Further <br />examination is necessary to determine-their trophic status.