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smallest northern pike removed from the Gunnison River. However, many razorbacks in the second stocking were large enough to escape predation by all but the largest of the northern pike collected. Heavy predation on newly stocked razorback suckers by channel catfish Ictalurus punctatus and flathead catfish Pylodictis olivaris was considered to be the most important reason for their poor survival in the Gila River, Arizona (Marsh and Brooks 1989). In the upper basin, Osmundson (1987) reported heavy predation on age-1 Colorado squawfish stocked into gravel-pit ponds containing largemouth bass. Based on the results of those two studies, reducing the predator load in the Gunnison River should increase the survival of newly stocked razorback suckers. This is especially true for a species like northern pike which occupies the same habitats that young razorback suckers would be expected to use. The Gunnison River contains a small number of adult Colorado squawfish. Radiotelemetry indicated movement as far upstream as Hartland Diversion, but their center of distribution is 20 to 30 km downstream (Burdick 1995). All of the adult Colorado squawfish captured to date from the Gunnison would probably evade predation by northern pike because of their large size. However, large numbers of northern pike in the Gunnison might be able to limit recruitment of subadult fish that move upstream through the newly- constructed Redlands fishway. Nesler (1995) felt that limiting recruitment of subadult Colorado squawfish to the Yampa River population might be the biggest impact to the species there. He also felt that roundtail chub populations could be negatively affected by northern pike since chubs appear to be a preferred food item. The Gunnison River near Delta contains a healthy roundtail chub population (Burdick 1995) that could be reduced if northern pike are allowed to increase because of floodplain restoration or other management activity. The lazge white sucker population in the Gunnison River could also pose a threat to razorback suckers as well as to the still common flannelmouth sucker and bluehead sucker. There is a high incidence of hybridization between white sucker and the two native suckers in the Gunnison River. Their abundance could lead to hybridization with razorbacks when stocked fish mature and begin reproducing. Their high abundance in floodplain habitats and 15