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<br />002776 <br /> <br />1. The investigation of mOl:phological (shape) characteristics involves the use of canonical <br />discriminant and cluster analysis to categorize patterns of morphological variation at three <br />levels of biological organization: population, species, and generic. No tissue samples are <br />required for this type of analysis. <br /> <br />2. An a1lo~e investigation for a given fish species involves the analysis of the allozymes within <br />a tissue sample. An allozyme is defined as an enzyme produced by an allele at a structural <br />gene locus. In order to help "larifY this definition, the following additional definitions are <br />provided. <br />I. allele - one of two or more alternate forms of the same gene; alleles for the same <br />gene occur at the same locus. <br />2. gene - a segment of DNA that occupies a specific position (locus) on a <br />chromosome, is heritable, and has one or more specific effects on the <br />physical characteristics of an organism. <br /> <br />Through the use of an electrophoresis procedure, the allozymes can be separated within a <br />particular tissue sample to identifY the genetic variation within a species or population. <br /> <br />3. The investigation of mitochondrial DNA involves the analysis of tissue samples. These tissue <br />samples are analyzed to determine the sequence of the DNA found in the mitochondria of a <br />cell. The mitochondria is located outside of the cell nucleus and produces energy for the cell <br />through cellular respiration. The DNA found in the mitochondria is analyzed after applying <br />the enzyme, endonuclease, which breaks down the DNA chain into smaller pieces. The <br />sequence found in these smaller DNA chains is compared with other samples to determine if <br />genetic differences are present among populations. <br /> <br />Significant work in each of these areas began in 1991. Tissue samples were collected from chubs <br />located in Desolation Canyon on the Green River and Westwater and Cataract Canyons on the <br />Colorado River. These samples were collected to determine the intraspecific variation in the <br />morphology and genetics of Qili\ populations throughout the Colorado River Basin. Field surveys <br />of these populations were also completed while obtaining tissue samples. (U.S. Fish and Wildlife <br />Service 1991b) <br /> <br />Based on experience gained during 1991 tissue sampling, a revised sampling protocol was issued to <br />project participants on March 27, 1992. A highly successful non-lethal sampling program was <br />conducted in several habitats known to harbor endangered .GillI forms. This included re-sampling of <br />Yampa, Desolation, and Cataract Canyons. All of the additional 114 specimens sampled in 1992 <br />recovered from the tissue sampling procedure and were released alive. Moreover, four specimens <br />subjected to non-lethal procedures in 1991 were recaptured and showed extraordinary healing of <br />biopsy wounds. (U.S. Fish and Wildlife Service 1992) <br /> <br />Sampling of all upper basin large and small habitats was completed by mid-October of 1992. It was <br />believed that adequate sample sizes, based on probable population levels and hybridization <br />possibilities, were obtained from each habitat. However, no additional humpback chubs were <br />obtained from the Yampa River to augment the six taken in 199 I, though numerous roundtail chubs <br />were sampled in both years, and only two roundtails were sampled in the upper White River. (U.S. <br />Fish and Wildlife Service 1992) <br /> <br />16 <br />