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<br />ww <br /> <br />Procedures <br />We will determine the survival, reproductive success, and <br />bioaccumulation of selenium in razorback suckers in the restored <br />sites (Walter Walker state Wildlife Area and Adobe Creek) if <br />adult fish are available for stocking from the Colorado River <br />Fishery Project (CRFP). It is desirable to have several sites <br />with different levels of selenium (and other inorganics) <br />contamination in order to obtain a concentration-response <br />relation. Also, one site should contain close to background <br />concentrations of selenium to serve as a reference site. <br />Prior to stocking the fish at the sites, fish will be PIT <br />tagged, measured for total length and weight, and muscle plug <br />samples taken for selenium (and other contaminants if needed) <br />residue analysis. The number of fish to be stocked at a given <br />site is contingent on the number of adults available and their <br />genetic compatibility, but ideally enough fish shOUld be stocked <br />to provide at least five spawning pairs for assessment of <br />reproductive success. The fish should be stocked as early as <br />possible to allow them to accumulate selenium residues from both <br />water and dietary sources. <br />At 30-day intervals (after stocking), the fish will be <br />sampled using nets, electrofishing gear, or both in.cooperation <br />with the CRFP. Captured fish will be identified from their PIT <br />tag, sexed, measured for total length and weight, inspected for <br />general health, and muscle plugs be taken for selenium residue <br />analysis. An attempt will be made to estimate the food habits of <br />captured fish. At the time fish are sampled, samples of water, <br />sediment, benthos, and plankton will be taken for selenium <br />residue analysis. <br />When the proper environmental cues (primarily temperature) <br />are present to stimulate spawning in these fish, at least five <br />pairs will be collected and given hormone injections to induce <br />spawning in cooperation with the CRFP. The adults will be <br />identified from the PIT tags. Collection of sex products and <br />fertilization of eggs will be done in the field following <br /> <br />5 <br />