Laserfiche WebLink
Table 11. Achi-square analysis for habitat preference by YOY Gila spp. for habitats deeper than <br />0.7 m in the Westwater Canyon sub-reach (Colorado RK 204 - 199.4) of Westwater Canyon, <br />Utah. Data collected in late July and August, 1992, 1994, 1995, and 1996 and August - <br />Sept., 1993. <br /> <0.7m >0.7m Total <br />YOY chubs Observed 26 25 51 <br />present Expected 27.46 23.54 <br /> cell chi-square 0.08 0.09 <br />YOY chubs Observed 9 5 14 <br />not present Expected 7.54 6.4G <br /> cell chi-square 0.28 0.33 <br /> Total 35 30 65 <br />Overall chi-square = 0.78; p = 0.38 <br />Below the Canvon (RK185.6 - 176.0) <br />This reach is comprised of a canyon bound stretch, a transition area as the river leaves the <br />confines of Westwater, and an area of broad floodplain. As with the reach above the canyon, backwaters <br />were sampled most frequently (51.1%), but habitat diversity was greater below the canyon (Table 6). <br />Other commonly sampled habitat types were embayments (5.8 %), shorelines (11.6%), and the flooded <br />mouth of Cottonwood Wash (15.0%) at RK 179.5. The sampling program yielded a good estimate of <br />availability for all habitat types, again with the exception of shorelines which were likely under- <br />represented. <br />Once again, the multinomial analysis indicated there was no habitat preference at the presence / <br />absence level of resolution (p=0.86) (Table 12). A similar analysis which considers the number of YOY <br />chubs collected in each habitat type indicates there was significant heterogeneity in the shoreline habitats <br />(Table 13). With more chubs found there than was expected. <br />Table 12. Multinomial analysis for use of habitats by YOY Gila spp. in the Below Canyon sub-reach <br />(Colorado RK 185.6 - 176.0), Westwater Canyon, Utah. Data collected in July and August, <br />1992, 1994, and 1996 and July -Sept., 1993 and 1995. <br /> <br />HA$ITAT <br />TYPE <br /> <br />N= <br />Obs. % of <br />Hab. Type Obs. # of <br />habs w/YOY <br />chubs Exp. # of <br />Nabs w/YOY <br />chubs <br />Chi-square <br />factor. <br />BW 24 52.2 13 10.97 0.37 <br />SH 6 13.1 2 2.75 0.20 <br />EMB 4 8.7 1 1.83 0.37 <br />PO 2 4.3 1 0.90 0.01 <br />IP 2 4.3 0 0.90 0.90 <br />FT 7 15.2 4 3.19 0.21 <br />SC 1 2.2 0 0.46 0.46 <br />Overall Chi-square = 2.53; p=0.86; df=b <br />13 <br />