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DRAFTI7 <br />difficult to obtain continuous temperature readings from the shallow ends of backwaters because <br />fluctuating water levels would alternately expose and inundate any stationary instnunent. The <br />shallow ends of the backwaters are warmer during the day, but cool off so much at night that the <br />average temperature is lower than the main channel (personal observation). Unless the squawfish <br />move around constantly to take advantage of local differences in temperatures, the backwaters <br />would not provide consistently higher temperatures. There is some evidence that squawfish do <br />move in and out of backwaters in the morning and evening, but not to the extent they would be if <br />they were closely following temperature gradients (personal observa ' published <br />data). ~Qa N ~ ~'~~ ~ ~ <br />Mean average temperatures for May through October were consistently higher in the main <br />channel than in the backwaters. Mean maximum was only slightly higher in the backwaters than in <br />the main channel (Table 9). Although the differences are small, most were highly significant using <br />a paired t-test, although notably, not the differences between backwater maximum and MC <br />maximum (Table 10). These relationships were consistent from month to month (not shown). <br />Table 9. Mean maximum and average temperatures for the period of May 1 to October 30, 1993- <br />1996: Green River main channel and backwaters. <br /> USGS MCAVG MCMAX BAlAVG BAIMAX BA2AVG BA2MAX <br />1993 * 19.8 19.5 20.6 20.1 20.7 16.4 17.7 <br />1994 21.6 20.1 21.2 18.9 23.0 <br />1995 19.2 18.8 20.0 18.2 20.2^ 18.5^ 19.1^ <br />1996 21.4 <br />* July 24 -October 30 ^ May 1 -August 15 <br />There was a mildly positive correlation between total degree day accumulation (May- <br />-17- <br />