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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />Evidence leading to the possibility of spawning by humpback chub in the <br />Little Snake River includes the following. Humpback chub occupied habitats in the <br />Little Snake River during their spawning period which occurs between June and <br />July (Kaeding et al. 1990; Karp and Tyus 1990) and when daily temperatures in the <br />Little Snake River from June 21 until July 26 were 180 C (range 14.4-21.20 C) and <br />adequate for spawning. At 19.50 C (range 14.5-230 C) humpback chub captured in <br />the Yampa River were in breeding condition (Karp and Tyus 1990). None of the <br />humpback chub that we captured had secondary sexual characteristics or <br />expressed gametes, but humpback chub with tubercles have been captured in June <br />in the same area of the Little Snake River (Wick et al. 1 991). Stronger evidence of <br />spawning in the Little Snake River would be the presence of ripe humpback chub, <br />especially females, but definitive proof of spawning will require collection of larval <br />or early juvenile humpback chub. We were unable to identify larval Gila beyond <br />genus because there were no adequate morphometric characteristics to distinguish <br />between larval roundtail chub and humpback chub in the small size range that we <br />captured. <br /> <br />Generally we accomplished our objectives for this study. We know what fish <br />species live in the Little Snake River, their distribution, and abundance. We also <br />have a better understanding of the habitat use by endangered Colorado pikeminnow <br />and humpback chub. But several questions remain, especially those regarding the <br />reasons for long-range movements and long-duration stay of humpback chub in the <br />Little Snake River. The predominant remaining question is whether or not <br />humpback chub were attempting to spawn in the Little Snake River. Specific <br />spawning sites have not been identified for humpback chub in the Upper Basin as <br />they have for Colorado pikeminnow and razorback sucker (Xyrauchen texanus), but <br />this knowledge could be crucial for management and recovery of the species. <br />Considering that so little is known about humpback chub reproductive ecology and <br />early life history, we believe that identifying specific spawning sites and describing <br /> <br />23 <br />