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~ Because of the large number offish collected in 1995 and 1996, total biomass of all fish collected was recorded, but length and weight data were subsampled. Total weight was determined for large (i.e. age-l +) fish by species. Subsamples of length and weight were obtained from each species batch weighed. Subsamples of small (age-O and small cyprinds) fishes were taken to estimate composition. Total weight of mixed species batches were recorded and subsample weights were used to determine the percent composition of the subsample. Subsamples of the original subsamples were taken to estimate length and weight distribution by species and total number in the overall sample. All small fish were scanned on a sorting table for the presence of native /listed species (with the exception of the last drain day in 1995 when volume of fish collected was beyond the capability of sorting, in this case samples were scanned for the presence of native fish in the seine after it was removed from the water). In 1996, fish in the drainage outlet were sampled with the same gear over time. Dates of fish collection were compared, by species, to determine if fish numbers collected differed over time. This effort included removal of fish with 25 mm mesh seines until large fish were removed, and then use of 3 mm mesh seines to capture smaller fishes during each collection day. For biomass comparison, the following sizes offish were considered age-O fish; carp <150 mm, green sunfish <75 mm, black bullhead Amierus melas <100 mm, channel catfish Ictalurus punctatus <150 mm, black crappie Pomoxis nigromaculatus <150 mm. Results In 1994, only five species were collected during wetland draining, whereas 15 and 16 species were collected in 1995 and 1996, respectively (Tables 4, 5, and 6). Northern pike Esox lucius was not collected in 1995. Sand shiners Notropis stramenius and speckled dace Rhynichthys osculus were identified only in 1996, but were probably present in 1995 and categorized as miscellaneous minnows. The biomass collected among years represented a standing stock of 12.6 kg/ha, 126.7 kg/ha, and 71.4 kg/ha in 1994, 1995 and 1996, respectively. The low biomass in 1994 was probably due both to the attempts to exclude fish in the spring and escapement through the drain. The composition of fishes collected during draining was dominated by nonnative fishes, particularly carp and fathead minnows. These two species together made up 94.4% of the weight and 78.9% of the fish collected in all three years. Carp made up the majority of biomass (90.4%) and fathead minnows were the most numerous fish (59.6%) collected during draining. Other species contributing over 1 % of either biomass or numbers among all years include green sunfish, black bullhead, channel catfish and red shiners. Adult fish accessing the wetland from the Green River dominated the biomass of fish collected when draining Old Charley Wash (Figure 15). Fish accessing the wetland directly from the Green River represented 84%,80%, and 77% of the biomass offish collected when the wetland was drained in 1994, 1995 and 1996, respectively (fathead minnows and red shiners were included in the category of fish produced in the wetland, although many probably accessed the wetland from the river). Although making up only a fraction of the biomass collected during draining, age-O fishes consisted of the majority of fish numbers collected. In 1995 and 1996 the biomass of age-O black bullhead and black crappie Pomoxis nigromaculatus was greater than age-l + fish. Biomass of age-O green sunfish was greater than age-l + fish in 1996. Razorback sucker was the most abundant native fish collected during draining Old Charley Wash in both 1995 and 1996. The 28 age-O razorback sucker collected in 1995 averaged 34