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The control reach (RM 120-115) is broader and lower gradient than the removal reach. Eddies ~ are less abundant and the channel is fiequently split by large islands and cobble bars. Substrate composition and riparian vegetation are similar to the removal reach. In addition, other physical characteristics such as temperature, turbidity, and flow were similar to the lower Green River removal reach over time due to the relative proximity of the two reaches. • METHODS Field work conducted for this project was split between Utah Division of Wildlife Resources (UDWR) and Utah State University (LJSU). USU performed all sampling in the middle Green River during both years. UDWR was responsible for the lower Green River in 1997, and USU ~ took on the remaining sampling conducted in 1998. Therefore, methods varied slightly between the middle and lower reaches of the Green River. Green River sampling trips Middle ~ In the middle Green River, a total of 12 removal trips were conducted from 6 August through 16 October 1997, and 19 June through 8 October 1998, following flood recession. In addition, an initial two day trip on 7-8 August 1997 was used to examine methods of setting and baiting fyke nets. ~ Fyke net removal trips consisted of six days of netting in the removal reach. Twelve fyke nets were set in each section yielding a density of three nets per mile in the middle Green River. During the first day, 12 nets were set in section one. On the second day, the nets in section one were cleaned and set in the second section. This process continued until day six when the nets were cleaned and removed from the river until the beginning of the next trip. In addition to netting, once each month, the removal reach was electrofished for two days, and the control reach was ekctrofished for one day. Five to ten river miles were shocked each day depending on catches and weather. ~ Lower In the lower Green River, a total of five removal trips were conducted from 29 July to 31 October in 1997 atxi six removal trips were conducted from 20 July to 22 October in 1998. In addition to sampling efforts in removal reaches, control reaches were also identified in the lower Green River during 1997. Of the four total reaches in the lower Green River, consisting of approximately two ~ codes each, two control reaches were set up between the two removal reaches. Therefore, the removal reaches were approximately RM's 140-138, and 136-134, and control reaches were approximately RM's 138-136, and 134-132. Three fyke nets were set in each control and removal reach, totaling twelve nets set per trip. One pass of electrofishing was conducted through the entire reach per trip. Fyke nets were generally set fora 24-hour period overnight. During trips S two and three, nets were set for one 24-hour period. During trips one and five, nets were set for two consecutive 24-hour periods. During trip four, nets were set for three consecutive 24-hour periods. Fyke nets were cleaned offish at the end of each 24-hour period and either pulled or reset. ~ 5