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For bluehead and flannelmouth suckers, condition was significantly (P < 0.05) higher in spring 1994 than in spring 1995. For bluehead suckers, condition during fall 1994 was significantly lower than in fall 1995. For flannelmouth suckers, condition during fall was similar between years. Roundtail chub condition during fall was similar between years as was condition during spring. To determine if condition in spring was related to seasonal enlargement of gonadal tissues, mean condition of immature and mature fish was compared. For all three species, condition of mature and immature fish during spring was not significantly different (Figure 12; Appendix Table 14). This was partly true for fall also. During fall of both years, condition of mature and immature roundtail chubs was similar. This was also the case for bluehead and flannelmouth suckers in fall 1994, but not in 1995, when immature fish condition was significantly higher than that of mature fish. Diet of Native Fish Among-Species Variation Miscellaneous organic debris made up the largest portion of the diet (by volume) for each of the three species examined (Figures 13-15). This mostly consisted of fibrous particles of vascular plant tissue and sometimes filamentous algae. Bluehead sucker diets contained the most organic debris (83 %), followed by flannelmouth sucker (55 %) and roundtail chub (43 %).' Invertebrates were the second most common food item of bluehead and flannelmouth suckers. Flannelmouth sucker diets contained a greater percentage of invertebrates than bluehead sucker diets (41% versus 16%). In bluehead sucker diets, chironomid larvae made up about half of the volume of invertebrates; in flannelmouth sucker diets, a third. Ephemeropteran and trichopteran larvae were important components of diets of both sucker species. In bluehead sucker diets, simulid larvae were also important; in flannelmouth sucker diets, chironomid pupae and plecopteran larvae were also important. The primary difference between the diets of roundtail chub and the suckers was the consumption of fish by roundtail chubs (Figure 15). Organic debris and algae made up approximately 57 % of the roundtail chub diet; fish made up 29 %; invertebrates, 12 %. Most of the fish remains in the diet consisted of unidentifiable parts; cyprinids made up most of those that could be identified. Ephemeropteran and trichopteran larvae were important components of the invertebrate portion of the roundtail chub diet. 'Diets of these three native species, as depicted in Figures 13-15, were derived by weighting the diet of fish from each strata according to how abundant the species was in that strata. The graphs thus depict diets of the overall population, i.e., those strata with the highest catch rates of a given species have the most influence on the overall diet. Diets of fish within each strata were averaged (strata averages for each period were then averaged across periods) and catch rates from the fall 1994, and spring and fall 1995 electrofishing efforts (periods averaged) were used for weighting. 24