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RESULTS AND DISCUSSION: SUMMARY The focus of the Utah State University study was to describe in a broad and historical perspective the process of humpback chub habitat maintenance in Deso/Gray. rom work in the Grand Canyon, eddy habitats were identified as the critical habitat to support a population of humpback chub (Valdez and Ryel 1995), Juvenile and adult humpback chub equently use eddies and eddy fences (see Report A for a habitat description). Young of the ear humpback chub use shoreline low velocity areas, habitats that in Deso/Gray are most ofte formed by eddy action, but not necessarily flowing eddy habitats. Thus, the indirect link betwe n Report A and Bin this volume. The changes in channel morphology identified in the USU s dy are discussed as factors limiting the humpback chub population in Deso/Gray. Day et al. 1999 took a critical look at Gila spp. and Colorado pikeminn w reproductive success and young of the year habitat use. Similar in design to pikeminnow nu sexy habitat investigations in the floodplain reaches of the Green River (Trammell and Ch 1999; Day et al. 1999), this was the definitive data set for this life stage from 1994-1996. Theo ly failing of their investigations was that only three years of data were accumulated seriousl limiting their ability to develop relationships between- Green River flow and observed respon es in the fish community: Chart and Lentsch (1998) summarize data collected over a longer eriod of time. However, since 1985, in some analyses, their single annual fish community s pling effort was more subject to the problems of sampling efficiency, particularly with regard to the YOY monitoring data subset. Data from these monitoring efforts was used to bolster the YOY analyses when possible, and provides the assessment of recruitment to the Age + year class. Several of the salient points of each study are summarized in Table 2, while sp cific project findings are discussed in the text. ,. ;~, .<`i viii