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-3- The endangered humpback chub is now known to harbor pure breeding stocks only in the Yampa River of Colorado, but a. breeding population may also occur in and near the mouth of the Little Colorado River. For this reason, no man- produced environmental disturbances should be undertaken anywhere on that river, which also provides good habitat for the reproduction and maintenance of all 1 o~a~na,ti~e fishes of this part of the Colorado. w,_ Speckled dace were taken along the river and in tributaries at many places, with one exception this year. Tr~peats Creek seems now to have been taken over entirely by the exotic rainbow trout. In contrast to a collection made there in 1968, no Rhinichthys osculus were secured in 1975 despite repeated and thorough efforts to obtain them. Since. no eomparativ~e study of the many speckled dace pop- ulations between Paris River (jest below Lee's Ferry) and Spencer Canyon has been made, it is not possible to estimate how much of a loss to science. the seeming disappearance of the TQ,peats population may be. It is known that dace in and above Paris River and those in the Virgin River basin, below the area surveyed, represent several distinctive forma. It is hoped that adults of Gila cypha can be taken alive and reared, as at the Willow Eeach hatchery facility. In addition to sound management principles for restoring this species, it would be extremely valuable to have a preserved series of known individuals of the humpback chub in order to facilitate identi- fication of juveniles of the species. At the present time only larger fish can be positively identified because the distinctive hump does not develop until the fish are approaching adult size. Consequently our specimens (juveniles) from the mouth of the Little Colorado River are simply assigned to the Gila robusta complex. I understand (from W. L. Minckley) that Gila elegans, the bonytail~is being cultured at the ~;illow Beach hatchery.. This is encouraging news since this species