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positively identify roundtail chub, Gila robusta, in northern pike stomachs taken from the Yampa River, but presumably one Gila spp. was a roundtail chub. T.P. Nesler (personal communication) reported roundtail chub were present in northern pike stomachs he examined from the Yampa River. Most of the pike we examined were from the Green River where roundtail chub are rare (Tyus et al 1982), and this may have resulted in the relative absence of roundtail chub as prey in pike stomachs we examined. Northern pike may spawn in the mainstream Green River, but if so, recruitment is presumed low. We did not capture small northern pike (<321mm TL) in this study, and to our knowledge, pike reproduction has not been noted there by others. However, one 115 mm TL specimen was seined by HMT and others from a shoreline area of the Green River in Dinosaur National Monument on 8 July 1988. It is not known whether this fish hatched in the Green River or was transported there from another location. Also, we captured several ripe female pike, and it is possible that some of these fish spawned in the Green River. Most ripe female pike (76%) had empty stomachs, suggesting a reduction in feeding activity with increasing water temperatures and ripening ovaries (Frost 1954, Lawler 1965). Walleye were rare in the Green River, and their long period of residency suggests that their numbers will probably not increase. Walleye were easily captured by electrofishing, and very few fish sighted escaped capture. However, it was difficult to capture northern pike with electrofishing, and many fish escaped. A direct comparison of the relative abundance of walleye with that of northern pike could be somewhat misleading, and it is noted that walleye were more rare, and northern pike more abundant, than indicated by electrofishing catch rates. We captured only one female walleye with developed 7