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pattern than mottled sculpin, being most common in Browns Park, and were abundant there in spring of each year (Fig. 38). Mountain whitefish was relatively abundant in spring 2003 seine samples in Lodore Canyon, but rare in all other years, reaches, and seasons. Mountain whitefish was most abundant in 2003, and we found a limited number as far downstream as Island- Rainbow Park in spring, but few otherwise. Too few Colorado pikeminnow were captured in seine samples to graph results; we discuss young pikeminnow captures in the species accounts section. Only one bonytail, and no humpback chub or razorback sucker was captured in seine samples. Abundance patterns of the most common non-native fishes, red shiner and sand shiner, generally increased in a downstream direction, being rare or absent in Browns Park, and abundant downstream (Fig. 26, 27, 39). Fathead minnow was most common in upstream Browns Park and declined in abundance downstream (Fig. 29, 40). Seasonal abundance patterns of red shiner, sand shiner, and fathead minnow were highly variable, but generally increased from spring to summer to autumn. Annual abundance was highest in 2002 and 2003 but lower in 2004. Higher spring abundance was not always associated with higher autumn abundance the previous year. Green sunfish abundance was highest in Lodore Canyon and generally low elsewhere (Fig. 40). In Lodore Canyon, spring and summer abundance was relatively low and autumn abundance higher. Patterns elsewhere were variable. Redside shiner and white sucker showed some consistencies in abundance patterns, being more common in upstream Browns Park than in downstream reaches (Fig. 28, 30,41). White sucker showed seasonal abundance patterns similar to native suckers, relatively low in spring, relatively high in summer, and lower in autumn, and was most abundant in 2002 over all seasons, especially in Browns Park. Redside shiner abundance was relatively high in spring and summer, but lower in autumn except in Browns Park and Lodore Canyon in 2003, where autumn abundance was quite high. Smallmouth bass were not found in Browns Park, but were more common in downstream reaches (Fig. 42). Spring abundance of smallmouth bass was low, relatively high in summer, and lower in autumn. Abundance was lowest in 2002 and higher in 2003 and 2004. 42