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12 I I I I I I I I I I I I ,I I J I I I I killifish (Fundulus zebrinus). Number of larvae captured (n = 5842) was about equal to number of juveniles and adults combined (n = 5528). Four humpback chub (250 - 292-mm total length) were captured from RK 5.6-14.5 in the Little Snake River in June and July (Table 6). One of these fish was subsequently recaptured on two additional occasions in the Little Snake River. All were captured in eddies by either trammel net or angling with Mormon cricket (Anabrus simplex) bait. Two humpback chub were captured together from an eddy at RK 13.2 and a Colorado pikeminnow was also captured from this same eddy 2 weeks earlier. Although all four humpback chub were large enough to be sexually mature lGorman and Stone 1997), none of the humpback chub had tubercles or other secondary sexual characteristics when captured. Three adult Colorado pikeminnow (510 - 830-mm total length) were captured from RK 9.2-14 in the Little Snake River in June and July (Table 6). Two Colorado pikeminnow were captured in eddies by electrofishing boat or trammel net and one was captured from a low-velocity shoreline by angling with a Mormon cricket. None of the Colorado pikeminnow had tubercles or other secondary sexual characteristics. Larval fish were collected in the Little Snake River only during descending runoff and baseflow periods and comprised only four large-bodied and five small- bodied species lTable 7). Most taxa were native. Bluehead sucker and flannel mouth sucker composed 97% of all larvae of large-bodied species and native speckled dace composed 85% of all larvae of small-bodied species. Sand shiner, were the most abundant nonnative larvae collected, but still composed only 8% of all larvae. Red shiner, fathead minnow, and redside shiner each composed only a small portion (::;3%) of larvae collected. Even though seining effort was relatively