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reproduction in 1988. A large number of the channel catfish electrofished in October 1988 were Age 0 or YOY fish. Our late- July seining data verifies the success of the 1988 channel catfish spawn. The number of species captured by electrofishing in 1987 declined from 13 to 9 in 1987. Missing from the 1988 collections were: roundtail chub (1 in 1987), fathead minnow (Pimephales promelas) (1 in 1987), black bullhead (Ictalurus melas) (1 in 1987), bluegill (Lepomis macrochirus) (2 in 1987), and mottled sculpin (Cottus bairdi) (9 in 1987). These species collectively accounted for less than 0.2% of the 1987 total catch. The only species that were not captured in 1988 by either electrofishing or seining were bluegill and mottled sculpin. The absence of bluegill is not surprising, as we have few records of any centrarchids from the study area. The lack of mottled sculpin from our collections (either electrofishing or seining) is an artifact of its distribution as the species is most common in the upper reaches of the San Juan River and its tributaries. Based on our 1987 survey, the downstream-most distribution of mottled sculpin appears to be in the vicinity of River Mile 184. This locale, which is five miles upstream of the Hogback, is outside of our current study area. Flannelmouth x bluehead sucker hybrid was more prominent in our 1988 samples than in 1987. Twenty-eight specimens were taken in the 87 samples in 1988, and this form was the sixth most abundant fish (Table 3). In 1987, only five of these hybrids were recorded-- thereby ranking it eighth in abundance. 17