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<br />Ww <br /> <br />procedures used by the CRFP. <br />After the eggs have water hardened, they will be transferred <br />to the mobile laboratory. For each spawning pair, several groups <br />of eggs (50-100) will be placed in incubator cups for viability <br />and hatchability determinations. The remaining eggs will be <br />saved for selenium (and other inorganics) residue analysis. The <br />incubation cups will be suspended in vessels filled with filtered <br />site water that is renewed daily. The number of live and dead <br />eggs will be recorded daily and all dead eggs will be removed. <br />When the larvae begin to hatch, the number of live, deformed, and <br />dead larvae will be recorded daily and all dead larvae removed. <br />After all the viable eggs have hatched, groups of larvae <br />from each cup will be transferred to larval exposure chambers for <br />30 days to assess survival, growth, and abnormal development. <br />The remaining larvae will be saved for selenium (and other <br />inorganics) residue analysis. The larvae will be held in vessels <br />containing filtered site water that is renewed daily and fed <br />plankton collected at the site. After the 3D-day grow-out <br />period, the surviving fish will be measured for total length and <br />weight and saved for selenium residue analysis. The information <br />obtained from this study will provide a meaningful link between <br />selenium resid~es in tissues and reproductive success of <br />razorback sucker. <br /> <br />Task 3. <br /> <br />Evaluate restored sites as nursery and grow-out areas <br />for razorback sucker larvae. <br /> <br />Rationale <br />Restored sites in the floodplain of the Colorado River are <br />expected to provide suitable habitat for early life stages of <br />razorback sucker and other listed fishes. These sites could be <br />used as grow-out areas for stocked larvae to produce fish of <br />sufficient size (about 10 cm in length) that increases their <br />chance of recruitment to adults. These fish can then be tagged <br /> <br />6 <br />