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<br />002751 <br /> <br />chubs), (2) genetic survey of razorback sucker, and (3) genetic survey of Colorado Squawfish. <br />The participation of a small group of noted genetic conservation specialists, designated as the <br />Genetics Panel, provides ongoing peer review and advice to the Recovery Program regarding <br />genetics activities. <br /> <br />Genetic Survey of Gila complex: The genetic survey of the Qi1a complex was initiated due to <br />uncertainty about the taxonomy of the species in the genus Qi1a (bonytail, humpback, and round tail <br />chubs). In 1990, contracts were awarded to perform research in three areas of genetic significance: <br />(1) morphological characteristics, (2) allozyme analysis, and (3) mitochondrial DNA (mtDNA) <br />analysis. Significant work in each of these areas began in 1991. A total of 1185 specimens were <br />sampled for correlated genetic and morphological studies of which 867 represented freshly sampled <br />wild populations while 318 were based on captive populations. Acquisition of raw morphological <br />data in the form of video-camera images fed into a computer data base was completed in 1993. This <br />data base included most of the approximately 1200 newly acquired (via non-lethal or conventional <br />sampling) chub specimens from wild populations and an additional 460 captive specimens to <br />supplement data form these populations or to represent extinct ones. Research efforts in 1997 to <br />complete the survey will focus on completion of a report on the mitochondrial DNA analyses, <br />additional analysis of allozyme data using more sensitive methods, and data synthesis. Much of the <br />data synthesis will be done by the various authors of the three parts of the Gila taxonomy analysis as <br />they draw conclusions on their work. The Genetics Panel will be convened to review the resulting <br />reports. <br /> <br />Genetic'survey of razorback sucker: The genetic survey of the razorback sucker was initiated in <br />May, 1990 in order to quantify genetic variation within and among the existing razorback sucker <br />populations. This survey has been completed. The final draft of "Genetic Diversity of Razorback <br />Sucker as DetemUned by Restriction Endonuclease Analysis of Mitochondrial DNA" was submitted <br />in December, 1993. This report concluded that existing natural populations of razorback sucker have <br />been interconnected by considerable gene flow or have become isolated so recently that mtDNA <br />differences have yet to accumulate. Furthermore, a high diversity among the natural populations <br />indicated surviving individuals were produced by a large number offemales, likely more than exist <br />in the region today. This high diversity and lack of appreciable differentiation of existing populations <br />is consistent with considerable interconnection of regions. The results indicated that there are no <br />genetic differences among razorback stocks in the Upper Colorado River Basin. However, there is <br />more genetic diversity in the Lower Basin population. The study also concluded that concerns over <br />hybridization should focus on other species, as introduced (non-native) species (e.g., white suckers, <br />flannel mouth suckers) are most likely to have the greatest impact on ll!l native Colorado River <br />species. <br /> <br />Genetic survey of Colorado squawfish: A genetic survey of Colorado squawfish was initiated in <br />1991. The genetic analyses associated with this survey should be completed in 1997. According to <br />preliminary interpretations of the completed genetic data, there appears to be random mating among <br />all Colorado squawfish, regardless of possible past genetic differentiation. These results strongly <br />indicate that no isolation existed among Colorado squawfish populations in the recent past and that <br />there are no genetic differences among Colorado squawfish populations in the Upper Basin. <br /> <br />VI <br />