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002800 Develop and implement an artificial propagation and rearing plan Assess and refine propagation tecbniques to maximize survival in tbewild Maximize genetic diversity Rear bonytail cbub to a size tbat promotes good post stocking sunrival Conduct experimental stocking of bony tail chub and identify priority recovery sites Stock bon)1ail chub in priority reco,"'ery sites 3, Resolve taxonomic problems in Colorado River Basin .GilA Stocking efforts associated with the bony tail chub have been minimal. A "Bony tail Reintroduction Plan for the Upper Colorado River Basin" (Lentsch et al. 1996) was submitted in 1996. This exoerimental plan identified the source of broodstock and the number, size, location, and condition offish when released. In addition, this plan includes evaluation and monitoring guidelines to evaluate the effectiveness of the stocking. This experimental plan will not achieve recovery goals. At present there is no plan for achieving recovery through stocking. The bony tail reintroduction plan allows for adaptive management as new and improved propagation information becomes available. Genetic diversity is maximized and maintained by following the "Genetics Management Guidelines" (Williamson et af. 1994). These guidelines describe the broodstock development matrix to be followed, provided sufficient wild adult broodstock are available. The experimental bony tail reintroduction plan includes a discussion on the optimum fish size for stocking The target length isfrom IOO-150mm Total Length when released. In an attempt to study bony tail habitat use, movement, and survivorship. and experimental stocking project was conducted in 1988. Over the period of the study, a total of 86 bony toil chub were surgically imp/anted with radio transmitters and released into the Green River in Dinosaur National Monument. The documented mortality rate was 74.5% and the telemetry study afmovement patterns was inconclusive due to operations of Flaming Gorge Dam. Identification of priority sites was essentially completed with designation of critical habitat for the bony tail chub (59 FR 54. March 21, 1994). The priority recovery sites are essentially the designated critical habitat. Large-scale, res/oration stocking programs have not been addressed by the Recovery Program. Future restoration stocking efforts should be targeted towards the priority recovery sites within the designated cri/ical habitat. At present there is no plan to stock bony tail in priority sites to achieve recovery. and no facilities that would enable production for recovery stocking purposes. Investigations associated with the Gila complex began in 1989. Tissue samples were collected from bony tail, humpback. and roundtail chubs located in the priority recovery sites, and those located in refugia, to determine the intraspecific variation in the genetics of the various populations. A morphological study was performed concurrently with the genetic analyses to investigate the intra- and interspecific morphological variation. The morphological study was completed and provided evidence to support the hypothesis that the Gila complex in the Colorado 40