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26 <br />Other explanations for the large percentage of empty stomachs <br />in captured bass include: 1) rapid rate of digestion (Merriman, 1941; <br />Raney, 1952), 2) sporadic feeding, and 3) regurgitation of stomach <br />' - contents by gillnetted fish. Regurgitation of food by gillnetted <br />fish is a common phenomenon and results in lower estimates of the <br />percentage of fish feeding. The components of the diet are not <br />affected by regurgitation, only the percentage of stomachs containing <br />food. In our study, the similarity of the percentage of stomachs <br />containing food (30%) and intestinal tracts containing food (41%) <br />suggested that regurgitation was not a major problem because regurg- <br />itation does not evacuate the intestine. Rapid digestion rate can <br />alter composition of stomach contents by digestion of soft-bodied <br />organisms first, but was also not considered a problem because most <br />of the food items were fish which should dissolve at a somewhat <br />similar rate. <br />Incidental to the bass study, walleye and catfish stomachs <br />were collected (Table 7). Approximately 60% of walleye and 50% <br />of catfish stomachs contained food. Shad was the most common food <br />item; carp and catfish were also consumed. Walleye fed most heavily <br />on threadfin shad, whereas channel catfish had a more varied diet. <br />Adult striped bass evidently do not often prey on native fishes <br />during the spring and early summer while in the Gypsum Canyon area. <br />Threadfin shad appear to provide tha major food source within the <br />reservoir for striped bass. Although endemic species were not found <br />in bass stomachs, adult Colorado squawfish and razorback sucker <br />were captured along with striped bass near Gypsum Canyon. Four small'