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Specific analysis relating species associations between all fish species by habitat will be provided later. Analysis of variance will be • used for significance testing-for different flow conditions. Rare Vinher. Specific information about the life history of four target species, Colorado squawfish, humpback chub, bonytail chub, and razorback sucker is presented.in this section. General information was also presented in the preceding section on the habitat and relationships of all fishes. Colorado squawfish Distribution and relative abundance Distribution and abundance information was presented for all fish species in the preceding section. When all collections were combined a total of 5,422 YOY, 403 juvenile, and 185 adult Colorado squawfish were collected from 1979 to 1981. These data are heavily biased since dif- ferent programs resulted in different procedures. Also, many more collections were made in some strata than others. For these reasons, only results from the standardized sampling program were used to obtain relative abundance data. The abundance of Colorado squawfish collected at standardized sampling stations for different size classes is given in Table 8. Total numbers of Colorado squawfish for YOY, juveniles, and adults (Figure 12) were used to produce a catch curve for each stratum. Strata A, B, C, and E produced the expected histographs with the numbers of young exceeding juveniles and juveniles exceeding adults in turn. However, the histo- graph was distorted in strata D and F, with smaller than expected young relative to the numbers of adults. The distribution and relative abundance of YOY Colorado squawfish was studied by a special investigations program in 1979 and 1981. In 1981, both larval and larger young were collected. Adult Colorado squawfish (TL 400 millimeters) were most abundant in strata F and E and least abundant in strata C and D (Table 8). Although data from the standardized sampling stations were used for these compari- sons (since effort expended in each stratum was equivalent), other collections also tended to support these observations. Colorado squaw- fish of over 700 millimeters TL were extremely rare and only one specimen was collected in the standardized collections. Adult Colorado squawfish were rare in overall sampling, amounting to only 14 percent of Colorado squawfish collected. E 32