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recovery effort (Brooks et al. and Marsh, both In prep.). <br />Present habitat conditions in the study area are degraded from <br />historic times when razorback sucker occurred there naturally <br />(Hinckley 1973, Brown 1982, Hendrickson and Hinckley 1984) but <br />this does not appear as significant as other factors in affecting <br />the outcome of attempted recovery. Thus, prospects for recovery <br />of razorback sucker are dependent upon management techniques used <br />to enhance survival of stocked fish. <br />Hatchery environment can greatly affect the survivability of <br />hatchery-reared fish (Miller 1953, Brown 1961, Eipper 1963, Keith <br />1969, Moring and Buchanan 1978). The well documented downstream <br />dispersal of stocked fish, including razorback sucker (Brooks et <br />al. In prep.) is a factor that can be partially compensated for <br />by selecting stocking sites in upstream locations. It is also <br />possible that conventional pond rearing (Hamman In press.) may <br />adversely affect a razorback sucker's ability to adapt rapidly to <br />the lotic environment when stocked. Hatchery based experiments <br />could evaluate response of hatchery reared fish to raceway <br />conditioning prior to stocking. Differences noted in these <br />experiments could be further evaluated in dispersal studies under <br />natural conditions (e.g. in the Gila River). Raceways and an <br />artificial stream at DNFH would provide facilities for such <br />experimentation. <br />Predation by introduced fish species is~ and will be a <br />fixture of southwestern rivers for the foreseeable future. <br />Removal or reduction of the predation threattta stocked razorback <br />sucker as requisite to the species' recovery is a foregone <br />-8- <br />