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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />health, and muscle plugs were taken for selenium analysis. Two fish from each group held at the <br />three exposure sites were sacrificed after spawning, after 30 days, and after 60 days in the <br />depuration phase of the study for analysis of selenium concentrations in various tissues. The <br />following samples were taken from each fish: muscle tissue from the dorsal area close to where <br />muscle plugs were removed, liver, kidney, gonad, gall bladder, and gut contents (only two fish). <br />The samples were placed in Whirl-Pak bags and stored frozen at -200C until chemical analysis. <br /> <br />Informal observations of adult razorback sucker <br /> <br />Five adult male razorback sucker used in an electroshocking study (Muth and Ruppert <br />1996) were held at North Pond in a hoop net for 89 days (March 5 - June 2, 1995). The purpose <br />of the informal observation was to determine if adult razorback sucker could survive in North <br />Pond with selenium concentrations in water as high as 170 /lgIL. This test was conducted prior <br />to stocking the young adults in the reproduction study. Fish had limited access to bottom <br />sediments and received a commercial fish diet (Silvercup, Nelson & Sons, Murray, UT) <br />approximately every 7-10 days. Duplicate samples of the commercial fish food diet were <br />collected for analysis of selenium concentrations. At 0,30,60, and 89 days of exposure, fish had <br />muscle plugs collected as described previously. After 89 days of exposure, fish were sacrificed <br />and stored frozen until selenium analysis of various tissues. The following samples were taken <br />from each fish: muscle tissue from the dorsal area close to where muscle plugs were removed, <br />liver, kidney, gonad, and gall bladder (no gut contents were available). The samples were placed <br />in Whirl-Pak bags and stored frozen at -20oC until analysis of selenium concentrations. <br /> <br />Water and sediment sampling <br /> <br />Beginning in mid-April 1995, selected water quality characteristics were measured every <br />week in situ at most of the 17 sample stations at the three test sites (Figures 3, 4, 5). In addition, <br />water samples were collected at 17 stations every 30 days and analyzed for general water quality <br />characteristics in the mobile laboratory. Water quality characteristics measured in situ at each <br />site included pH, conductivity, salinity, air temperature, water temperature, and dissolved <br />oxygen. Water quality measurements in water samples measured in the mobile laboratory <br />included pH, conductivity, hardness, calcium, magnesium, alkalinity, and chloride. Two <br />subsamples of each sample taken to the mobile laboratory were collected in polyethylene bottles. <br />One sample was used for alnmonia analysis and was acidified to a pH <2 with concentrated <br />sulfuric acid. The other sample was used for analysis of nitrate, nitrite, sulfate, total suspended <br />solids, volatile solids, and fixed solids and was stored in a refrigerator at 40C. These subsamples <br />were then shipped in a cooler with ice packs by overnight express to Yankton Field Research <br />Station (FRS), SD, for analysis. All water quality characteristics were measured according to <br />standard methods (APHA et al. 1995), except for the nitrogenous chemicals and chloride. <br />Ammonia, nitrate, and nitrite were measured using ion-selective electrodes and following the <br />procedures for low concentration measurements of the electrode manufacturer (Orion Research <br />1990, 1991; AT! Orion 1994). Chloride was measured by a modification of the APHA et al. <br />(1995) method (Hach Company 1992). <br />Subsamples of water collected between May 1995 and June 1996 for water quality <br />analyses from the 17 sample stations were taken for selenium analysis and ICP analysis of <br /> <br />18 <br />