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<br />to coincide with the final BIS and that Reclamation would provide comments on the draft <br />.biological opinion. Those comments were provided August 16 and incorporated into this draft. <br />A draft of the reasonable and prodent alternative was provided to Reclamation September 1. <br />The following biological opinion is based on information provided by the Glen Canyon <br />Environmental Studies (GCES) including endangered fish annual research reports for <br />Conservation Measure Five, information in the Preliminary Draft BIS dated January 8, 1993, <br />the Advanced Draft EIS dated July 1993, data in our files, and other sources of information. <br />Additionally, because final GCES technical and integration reports are not scheduled to be <br />completed until January and April 1995, the benefit of those analyses was not available for this <br />biological opinion. <br /> <br />BIOWGICAL OPINION <br /> <br />It is my biological opinion that the proposed operation of Glen Canyon Dam according to <br />operating and other criteria of the MLFF, as described in the Preliminary Draft ElS, is likely <br />to jeopardize the continued existence of the humpback chub and razorback sucker. It is my <br />biological opinion that the proposed operation of Glen Canyon Dam according to operating and <br />other criteria of the MLFF, as described in the Preliminary Draft EIS, is not likely to jeopardize <br />the continued existence of the bald eagle, Kailab ambersnail, or peregrine falcon. Proposed <br />critical habitat for the humpback chub and razorback sucker will be addressed in a separate <br />conference report when background material to support the listing role is released. This report <br />will include aily other species proposed for listing at that time. This biological opinion supports <br />maintenance of biological diversity associated with the pre-dam hydrograph and the dependent <br />ecosystem components including other native fishes. <br /> <br />DESCRIPTION OF PROJECT <br /> <br />BACKGROUND <br /> <br />Glen Canyon Dam was completed in 1963 as a feature of the Colorado River Storage Project <br />(CRSP). At Reclamation's request, a biological opinion was prepared on May 25, 1978, on the <br />effects of the dam on the Colorado River. That opinion found that past, present, and future <br />operations of the dam jeopardized the continued existence of the humpback chub and limited <br />recovery of the humpback chub and Colorado squawfish (Ptychocheilus lucius). The Service <br />recommended studies to determine the potential impact of warming the release water, the <br />ecological needs of the species, methods to reduce known constraining factors of low <br />temperature and frequent fluctuations, and relationship between mainstem and tributaries and <br />utilization by species. Jeopardy was not included for the Colorado squawfish since it was <br />considered extirpated from Grand Canyon in 1978, and it remains in that status today. The <br />bony tail chub (Gila elegans) and razorback sucker were not listed in 1978 and, therefore, were <br />not included in the opinion. The bonytail chub, a species closely related to the humpback chub, <br />was listed as endangered in 1980, but is considl:red extirpated from the Grand Canyon. The <br />razorback sucker was listed as an endangered species in 1991. <br /> <br />13 October 1m Oraft biological opinion 2,21-93-F-167 <br /> <br />3 <br />