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Resource limitation <br />The response of relative growth gave no indication that resource <br />limitation was reduced at higher feeding regimes. The highest feeding regime <br />was thought to represent a superabundance of prey relative to number of fish, <br />but relative growth increased at all resource levels suggesting that <br />zooplankton were limiting. Rotifera and nauplii were the most abundant types <br />of zooplankton in collections and made up an average of 61 % total <br />zooplankton. However, rotifera and nauplii were identified in only 3 % of <br />fish guts. It is uncertain whether the low occurrence of these food items in <br />fish guts resulted from our inability to discern them from other contents, or <br />because they were not consumed by study fish. It was anticipated that <br />rotifera and nauplii would be consumed, at least at the beginning of the <br />experiment when fish were small. If they were consumed ear]y in the <br />experiment, but not at the end, diet analysis would have shown similar results <br />to those observed. Alternatively, if rotifera and nauplii were too small to <br />be consumed by fish (i.e., were not available), zooplankton availability was <br />overestimated. If zooplankton availability estimates are adjusted assuming <br />that rotifera and nauplii were not available to fish, then the actual feeding <br />regimes were 12, 31, and 78 rather than 32, 80, and <br />200 zooplankton•fish-~•day-~, respectively. <br />Diet overlay <br />Diet overlap varied slightly in response to changes in resource <br />availability. Diet overlap only decreased in the lowest feeding regime where <br />survival and growth responses indicated that resource competition was intense. <br />However, relative growth at other feeding regimes showed that competition <br />18 <br />