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I I I I I I I I I I I I I I I I I I I From May through October, five native and seven nonnative species were collected. We collected no endangered fishes even though we sampled the same sites where Wick et al. (1 991) previously captured humpback chub and Colorado squawfish. Of 4,490 fish collected, 69% were native species (Table 2). The most abundant taxa (31 %) were native bluehead sucker (Catostomus discobolus), 23% were flannelmouth sucker (Catostomus latipinnis), and 20% were nonnative redside shiner (Richardsonius balteatus). All of the five native species except mottled sculpin (Cottus baird/) and larval roundtail chub were relatively abundant (Figure 3; Appendix Figures C.1-C.5). The most common nonnative species collected were sand shiner (Notropis stramineus) and redside shiner, all other nonnative species were few in number (Table 2; Appendix Figures C.6-C.1 0) All common carp (Cyprinus carpio) and channel catfish (lctalurus punctatus) collected were adults or juveniles (Figure 4). Reproduction Collection of larvae confirmed reproduction in 1994 of native: roundtail chub, speckled dace (Rhinichthys osculus), bluehead sucker, flannelmouth sucker, and mottled sculpin and nonnative: red shiner (Cyprinella lutrensis), sand shiner, fathead minnow (Pimephales promelas), white sucker (Catostomus commersom), and redside shiner (Table 2). Few larvae of roundtail chub, mottled sculpin, red shiner, fathead minnow, or white sucker were collected and no larvae of channel catfish or common carp were collected. Roundtail chub spawned between late June and early July based on adult roundtail chub expressing milt on June 18, and with orange or red spawning color between June 18 and July 13. In mid-June, 49% of all roundtail chub (n = 16) collected were in spawning color while only 14% of roundtail chub (n = 59) collected in mid-July were in spawning color. Collections in May and June also 13