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Biologists will continue to bring in wild caught larvae from spawning aggregations until 2004. <br />The target of 200 individuals per year will be pooled from all spawning aggregations over the <br />duration of the spawning period. These individuals will be reared until large enough to PIT tag <br />and placed in ponds that contain an aggregation of young WC RBS broodstock. <br />Management activities in the rearing environment include incubation and rearing to <br />maturity offspring of hatchery produced fish and future broodstock. Dexter NFHTC will <br />minimize the effects of selection on offspring by maintaining low densities and family lot <br />integrity until individuals can be marked by family and put into `Nature's grow out ponds for <br />stocking as fingerlings. Equal numbers of individuals from each family lot will be maintained. <br />Historically, up to 100,000 fry/acre were stocked in Dexter NFHTC ponds for growout, and <br />survival was excellent. In an attempt to maximize growth and minimize the effects of density as a <br />selective factor and to initiate `Nature's rearing strategy, Dexter NFHTC will stock RBS fry at <br />50,000/acre, and after the first year reduce that number to 25,000/acre. Fish are placed in rearing <br />ponds where hatchery conditions mimic a natural backwater area or nursery habitat (Lynch and <br />O'Hely 2001). Dexter NFHTC pond environments include predation, natural pond populations of <br />aquatic insects as food and predators, diurnal fluctuations of temperature and oxygen, and aquatic <br />vegetation. These captive stock selection factors mimic many natural impoundments, and are <br />arguably cognate with many historical larval RBS rearing habitats (Lynch and O'Hely 2001). <br />This plan outlines a breeding strategy for RBS that maximizes effective population size of <br />the captive parental population and minimizes the genetic risks associated with hatchery practices. <br />Our breeding strategy will use data from a genetic screening to assess the relatedness of all <br />broodfish, produce a matrix that categorizes the relatedness of female and male broodfish <br />(Quellar and Goodnight 1989), and prohibit the use of broodfish fish that have a high genetic <br />similarity (Blouin et al. 1996; Quellar and Goodnight 1989; Norris et al. 2000). The matrix will <br />be used to provide the statistical basis for selecting or discarding potential broodfish. This will <br />29