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<br />This report details a multivariate analysis using digitized <br /> <br />measurements taken from photographs of live chubs from Green <br /> <br />River and mainstem Upper Colorado River locations as well 23 pre- <br /> <br />served specimens taken in 1953 from the Green River. <br /> <br />PCA is used <br /> <br />to generate hypotheses of relationship and demonstrate its <br /> <br />potential for better informed management of the endangered chubs. <br /> <br />MATERIALS AND METHODS <br /> <br />~;:rn <br /> <br />Each fish was photographed against a 1-cm2 division gridboard 2nd <br /> <br />measurements t~ken from the pictures with a Calcomp digitizer. <br /> <br />The distance measures consisted of those comprising box-trusses <br /> <br />(Bookstein et a1., 1985) as well as some traditional on~s (Hubbs <br /> <br />and Lagler, 1964), chosen for their ability to be repeatedly <br /> <br />taken from 3 X 5 inch black-and-white photographs (Figure 1). No <br /> <br />attempt was made to directly quantify the nuchal hump, although <br /> <br />it has been considered to be diagnostic by earlier workers (Smith <br /> <br />at aI., 1979). <br /> <br />Prior to measuring, points were identifierl 2nd <br /> <br />marked using a dissecting microscope. <br /> <br />Two-~undred and sixty-one animals were examined (Appendix 1). <br /> <br /> <br />These included 157 chubs captured by the UDWR during Summer 1985: <br /> <br /> <br />1. Coal Creek, Green River, River Mile (RM) 1u5.7 <br /> <br /> <br />2. G r e e n R i v e r, OR M 1 53 . 0 - 1 60. 4 <br /> <br />3. Jack's Rock, Green River, R~A 158.2 <br /> <br />4 <br />