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, , ,r". ~ , these flows likely could not be changed without a time- consuming NEPA compliance process for at least 10 years. * Little is known about the relationships of the specific flows to other river conditions and there likely will be a need to change the flows before the proposed period is over in response to documented problems. :: .. .;J . * A substantial time delay would occur while the necessary NEPA compliance and Secretary decision were obtained if changing the flows in the research program is needed due to an awareness that the research flows are causing a significant problem. , * The DEIS provides an incomplete assessment of the impacts of reduced flow fluctuation on reduced downstream productivity through drift of Cladophora. The DEIS offers plenty of supporting language for a need to sustain a high primary productivity level for Cladophora (pg. 104). This algae IIforms the basis of highly productive food chain below Glen Canyon Dam." and "The prolific growth of Cladophora has established the upper portion of the river as an important production area that feeds downstream reaches with particulate organic matter in the form of Cladophora and aquatic invertebrates entrained in current as drift, particularly during increasing flows or upramping. II Even though studies by Liebfried and Blinn (1988) and Angradi et al. (1992) demonstrate an increase in drift with increasing flows (that is, higher fluctuations in flow) the DEIS (pg. 211) incredibly says "the significance of less fluctuation-induced drift is unknown." " " .~ ~ t' ... '. " <:", '}.~ * Since temperatures are too cold for mainstem spawning, the larval fish. which might use backwaters created under this experiment must come from the warm LCR. Recent AGFD studies show a significant mortality occurs to larval fish exposed to temperatures found in the mainstem or they are sufficiently disoriented that predation may be a significant factor. * Can larvae be expected to 1) negotiate cold river water; 2) find a suitable backwater; 3) avoid predation en route; 4) avoid predation from nonnatives after entering a backwater if they find one; 5) survive competition with nonnativesi and 6) survive relocation downstream during Habitat Maintenance or Habitat Building Flows? * We question the validity of an interruptable five (5) year study of low flows to measure long-term effects on Humpback chub. Humpback chub are a long-lived species which evolved such longevity probably in response to a low frequency of satisfactory reproductive conditions. .', .. t' ,',;I p " ", 'i r~ e.;. ~ ;;~ 13