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~ '' t t 1 of red shiners (Notropsis lutrensis) which compete directly with young Colorado squawfish for food. In addition, most backwaters also contain large numbers of green sunfish and bluegills which .act as predators on Colorado squawfish eggs, fry, and fingerlings. There is little doubt that Colorado squawfish reproduction on the lower San Juan River would be :difficult, if not impossible, under current biological con- ditions. -Page 5 - Lt seems that two very important actions taken by the Fish and Wildlife Service (FWS) and the State Game and Fish agencies on the Green and San Juan Rivers, which have affected the Colorado squawfish, have not-been discussed. Specifically, we refer to the rotenone fish eradication program in 1962 carried out on the Green River in conjunc- tion with the closure of Flaming Gorge .Dam and a similar program initiated in conjunction with closure of Navajo Dam. Both of these activities most certainly contributed signifi- cantly to the decline of the endemic species in the Colorado River and its tributaries and should be discussed in the Recovery Plan. There may have been other such programs carried out on other sections of the Colorado River and its tributaries, and we feel strongly that the results of these programs and. how they may have affected the decline of the Colorado squawfish in the Colorado River Basin should be dis- cussed. Section 14 - In both the step-down plan and step-down narrative of this section, several future research requirements are listed. J-3 It is important that research includes plans to describe micro- habitat requirements of all life stages of the Colorado squaw- fish. Until these requirements are known, the effects of flow depletions on critical habitat cannot be adequately answered. Section 1221 - In the step-down narrative of this section, it states: "Trend zones in the Colorado River drainage will be J-4 established where Colorado squawfish are known to exist." The trend zones proposed for monitoring include the San Juan River from Bluff, Utah, downstream to Mexican Hat and the Salt River from the confluence of the White River and Black River down- stream to the State Route 288 bridge. Although both of these areas are historical habitat, no Colorado squawfish are cur- rently known to inhabit these sections. Page 27, Proposed Budget - Job 1144 - The CES, which the Bureau is presently writing, will compile a list of most of the major water-related projects in the Colorado River drainage. 2