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<br />C) <br /><":) <br />~.) <br />f.~" <br />( . ,~l <br />o <br /> <br />where Ei = number of eggs hatched on day Xi, n = number of days eggs incubated, and M = total <br /> <br />number of eggs hatched. <br /> <br />Larval survi val and growth <br /> <br />After all viable eggs hatched, 15 larvae from two egg cups were stocked into each growth <br /> <br />chamber (30 larvae per growth chamber and 60 larvae per spawn). Two growth chambers were <br /> <br />used to facilitate daily observations on the condition of the larvae. The larvae were held for 30 <br /> <br />days in clean test water at 21 ol:loC and fed live nauplii of brine shrimp (Artemia sp,) three times <br /> <br />a day. Mortality and oven abnormal behavior were monitored daily and total length (nearest <br /> <br />nun) and weight (nearest 0.001 g) were measured at the end of the 3D-day test period. Overall <br /> <br />survival of the progeny from a given spawn was calculated as the product of percent survival of <br /> <br />embryos and larvae in the egg cups at the time of thinning (when larvae were stocked into <br /> <br />growth chambers) times larval survival from thinning to the end of the test (ASTM 1992). <br /> <br />Progenv residues <br /> <br />Eggs not used in the hatchability and larval survival and growth studies were used in the <br /> <br />progeny residue study. After the eggs hatched, the larvae were transferred from the hatching jars <br /> <br />to the aquaria (described above). The larvae were held for 30 days in clean test water at 21 ol:loC <br /> <br />and fed live nauplii of brine shrimp and BioDiet Starter (BioProducts Inc., Warrenton, OR) ad <br /> <br />libitum. Mortality was recorded daily, and at 1-,16-, and 3D-days posthatch, composite samples <br /> <br />offish were collected from each aquarium for whole-body selenium residues. The fish were <br /> <br />euthanized with MS-222, weighed, packed in Whirl-Pak bags, and frozen until analysis, <br /> <br />Radio-tagging <br /> <br />On days 229 and 330 of study, radio transmitters (Advanced Telemetry Systems, Isanti, <br /> <br />MN) were surgically implanted in the body cavity of 13 fish by personnel of the Colorado River <br /> <br />18 <br />