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<br />Concern over endangered species. particularly endangered Kabab ambersnail, prompted development of a U.S'. <br />Fish and Wildlife Service biological Opinion in this federal action, A 2-3 October 1997 habitat and population <br />survey at Vaseys Paradise revealed that 29.8m2 of potential KAS habitat lay downslope from the 934 m3/s <br />(33,000 cfs) flood stage. Five habitat patches were predicted to be inundated and potentially scoured by the . <br />planned November Test Flow, but it was considered unlikely that the inundated vegetation would be completel' . <br />eliminated. The habitat in the flood zone was estimated to support approximately 181 KAS (less than I % of the <br />. estimated total population). Immediately prior to the November Test Flow, the Arizona Game and Fish <br />Department salvaged habitat and 14KAS from the inundated zone an is presently holding that material at the <br />Phoenix Zoo. A GCMRC survey crew reported new sand and driftwood on the inundated habitat patches <br />immediately following the event. Although losing 14.4% of the flood zone habitat to scour, the Test Flow did <br />not completely eliminate vegetation in the habitat patches of concern. No impacts were anticipated or observed <br />on endangered southwestern willow flycatcher habitat. hnpacts on endangered humpback chub were not <br />considered to be detectable, and hence no effort was made to monitor that species. <br /> <br />Conclusions <br /> <br />These preliminary results indicate that top-of-powerplant flows can be used to rebuild low-lying sand bar <br />plantforms, and result in little disruption of terrestrial endangered species. A flow of this magnitude is probably <br />insufficient to create or substantially rejuvenate backwater habitats, which serve as nursery habitats, for native <br />. and non-native fish. Although some sand bars increased in area and volume, this flow may not hayebeen of <br />sufficient dUration to maximize sand bar rebuilding; <br /> <br />'.' <br /> <br />." .",- <br /> <br />". :..-......... <br /> <br />, <br /> <br />-.>-";-o!"-" <br /> <br />: '. <br /> <br />. <br /> <br />.j <br /> <br />";. <br /> <br />. <br />..:) <br />