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<br />WW <br /> <br />their PIT tag, sexed, measured for total length and weight, inspected <br />for general health, and muscle plugs taken for selenium residue <br />analysis. At the time fish are sampled, samples of water, sediment, <br />benthos, and plankton will be taken for selenium residue analysis. <br /> <br />When the proper environmental cues are present to stimulate spawning <br />in these fish, at least five pairs will be collected and given hormone <br />injections to induce spawning in cooperation with the CRFP. The <br />adults will be identified from the PIT tags. Collection of sex <br />products and fertilization of eggs will be done in the field following <br />procedures used by the CRFP. <br /> <br />After the eggs have water hardened, they will be transferred to the <br />mobile laboratory for the remainder of the viability study. (See <br />attached proposal for detailS) . <br /> <br />Task 3. Evaluate restored sites as nursery and grow-out areas for <br />razorback sucker larvae. <br /> <br />Rationale <br />Resto~ed sites in the flood plain of the Colorado River are <br />expected to provide suitable habitat for early life stages of <br />razorback sucker and other listed fishes. These areas will be <br />available for drifting larvae to come into and/or these areas may <br />be 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. <br /> <br />Procedures <br />Survival, growth and bioaccumulation of selenium in larval <br />razorback suckers will be assessed in the restored sites by <br />conducting concurrent in situ and on-site studies if fish are <br />available. (For details, see attached proposal). It would be <br />desirable to locate each study site close to one of the monitoring <br />sites in Task 1. The fish will be obtained through cooperation <br />with CRFP after approval of the Genetics Panel. <br /> <br />In addition to testing razorback suckers, larval flannelmouth <br />suckers and fathead minnows may be tested at each site to assess <br />their potential as surrogates for razorback suckers. <br /> <br />VII. Task Description <br /> <br />(For details, see Study Methods/Approach of attached proposal) <br />1. Monitor candidate sites. <br /> <br />2. Evaluate survival and reproductive success of razorback sucker adults <br />stocked in restored sites. <br /> <br />3. Evaluate restored sites as nursery and grow-out areas for razorback <br />sucker larvae. <br /> <br />VIII. Study Schedule <br /> <br />Task 1. <br /> <br />Monitor candidate sites: <br />continuing for remainder <br />of 1996) . <br /> <br />Beginning in the spring of 1995 and <br />of study (approximately through the fall <br /> <br />Task 2. Evaluate survival and reproductive success of razorback sucker <br />adults stocked in restored sites: Beginning in the summer of 1995 <br />(with the availability of adult fiSh) and continuing through one <br />reproductive cycle of adult fish. <br /> <br />BC-ltI-D <br />