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,, ,, ""~' `' ~~ ,, ... v 4 squawfish distribution, captures by river mile, indicated some change from the previous reporting period (Figure 4). Cranney (1990) reported higher catch rates in the downstream portion of Reach 3, but no distinguishable patterns in the other reaches. This held true for Reach 2 between 1991 and 1994. However, Reach 3 showed no discernable pattern of distribution. In Reach 1, over 50% of the fish were captured in the upstream half of the reach (RM 334-331). In general, captures per mile in the Green River decreased in a downstream direction. Distribution data for the 1994 Elective Reach showed a similar result. In Reach 13 (White River), over 50% of the captures were made between RM 12 and RM 5. Captured squawfish ranged in length from 128 mm to 785 mm (Figure 5). Over three-quarters (76.6%) of these were between 400 mm and 600 mm~ ~ish,-were fairly evenly distributed outside this range. Size distribution ~ withi reaches mm~cked the 5- year, overall distribution (Figure 6). However, sizes in the Bland )?ark Reach were skewed toward longer fish. The smallest fish captured in that reach was 329 mm, while all other reaches recorded captures less than 200 mm. This distribution pattern is nearly identical to what Cranney (1990) reported for the preceding 4 years. However, there appears to have been an increase in the number of fish in the system shorter than 300 mm. Cranney (1990) reported only 2 fish in this range, while captures for this reporting period included 20 fish (12 in the standard reaches and 8 in the elective reaches) below 300 mm. ' The increases in squawfish captures and smaller squawfish captured are likely related to past productivity.. McAda et al (1994) reported a highly successful 1985 cohort recruiting into the system. Additionally, production in 1988 was higher than previously reported, although subsequent survival appears to have been low (McAda et al 1994). Fish from these cohorts would be in the 400-600 mm size class and are likely still recruiting to the population of the upper Green River. The increase in fish below 300 mm may be associated with high YOY catch rates in the fall of 1991. Mean CPUE for YOY squawfish in the upper Green River in 1991 was nearly as high as reported for 1986 (see Young-of-the-Year Monitoring). In addition, mean CPUE for sympatric nonnative fishes in 1991 was the lowest yet reported (Cranney 1990). Fish hatched in 1991 would likely be between 150 and 250 mm. A total 26 razorback suckers was captured/observed during the reporting period (Table 3). This represents a decrease of 65% from captures between 1986 and 1989 and is consistent with suspected status of the population. Nearly half of these (n=12) were captured in 1990. Razorback suckers were most commonly caught in Reach 2, wherein is found the only known spawning bar in the Green River (RM 311). No razorback suckers have been caught outside Reach 2 since 1992. Mean length of all razorback suckers was 518 mm with a range of 420-575 mm. Suspected razorback x flannelmouth sucker hybrids were captured on five occasions: 2 in Reaches 2 and 3, and 1 in the White River. 12