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The fry and fingerling stockings began in 1981 from fish produced at Dexter NFHTC using <br />broodstock collected from Lake Mohave (Brooks 1986). Over the next ten years, more than 11 <br />million hatchery produced fish were released into the Salt and Verde Rivers (Hendrickson 1994). <br />The stockings were considered unsuccessful as large populations of RBS were not established in <br />either system. Field surveys conducted by the Arizona Department of Game and Fish have found <br />no evidence of natural reproduction. The lack of recruitment and minimal survival is attributed to <br />habitat fragmentation, predation by exotic piscivores, downstream displacement due to high <br />velocity flows, lack of isolated backwaters, and heavy parasite infestations (Hendrickson 1994). <br />An assessment of stocking success conducted by the Arizona Department of Game and Fish for <br />the ten year augmentation effort indicated that very few RBS survived in either system for more <br />than one year. <br />Due to these threats, the augmentation program was adjusted to incorporate the stocking <br />of larger fish. Biologists believed larger fish would be less susceptible to predation and better <br />able to acclimate to the riverine habitat. Since 1993, stocking records indicate that approximately <br />20,000 RBS averaging 300 mm in length have been stocked into the Verde River near Childs and <br />Beasley Flats, Arizona. The fish stocked were of Lake Mohave origin and reared at the Bubbling <br />Ponds SFH and Dexter NFHTC. The majority of the fish stocked were marked with coded wire <br />tags for future monitoring activities. The Arizona Department of Game and Fish collected nine <br />razorback suckers averaging 400 mm in length in 2002 during the annual field surveys indicating <br />that a small number of stocked fish are surviving. We are unable to provide population estimates <br />due to insufficient data. Current management plans address stocking 2000 fish 300 mm in length <br />annually (Lake Mohave stock) in the Verde River. <br />Sampling efforts to date have found no RBS in the Salt River. Due to limited sampling <br />contact with any RBS in the Salt River and tribal concerns, all stockings were discontinued in <br />12