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Delta, Colorado, to Redlands Dam). In eazly-2003 (Kesler et al. 2003), an integrated stocking plan was finalized that served as an addendum to the previous stocking plans developed by Colorado (Kesler 2001) and Utah (Hudson 2001). The integrated plan (Kesler et al. 2003) unified the sepazate State stocking plans and included the San Juan River subbasin; the intent of this document was to add consistency throughout the Upper Colorado River Basin. For razorback sucker, the number of Age 2+ fish to be stocked annually in the Upper Colorado and Gunnison rivers was decreased from 16,440 to 9,930 due to the increase of multiple age groups from 3 to 4. This plan recommends maintaining four adult age classes, which would require stocking razorback sucker for 6 yeazs. The survival rate of adult razorback sucker (0.70) and the recovery goal abundance buffer of 30% remained unchanged. The stocking of 3,310 razorback sucker and 1,125 Colorado p~eminnow per year was recommended to meet the objective of establishing a multi-age group adult population at the designated population abundance level and estimated survivorship as defined in the recovery goals (U. S. Fish and Wildlife Service [FWS] 2002) for each species in the Upper Colorado River Basin. Stocking wild and domestic-reazed sub-adult and/or young adult Colorado pikeminnow from downstream reaches of the Upper Colorado River via translocation proposed during this study was believed to provide useful information on residency, movement within the stocked reach, possible downstream migration over the Government Highline Diversion Dam, and possible movement inxo the Government Highline Canal. Lazge sub-adult (42050 mm) and young adult (450-550 mm) Colorado pikeminnow have been shown to exhibit greater upstream dispersal distances (mean of 20.9 miles upstream) than larger (greater than 550 mm; mean of 4.7 miles) Colorado p~eminnow in the Upper Colorado River (Osmundson et aL 199$). Several hypotheses (see Osmundson et aL 1998) were offered for the upstream movements by smaller Colorado pdcenainnow: 1) a response to food resource gradients, i.e., movements may be motivated by hunger, 2) an innate physiological mechanism to move upstream, and 3) the urge to spawn with better foraging areas discovered in the process. Colorado p~eminnow less than 550 mm may not have established a home range like that of their larger counterparts. Their inclination to move long distances upstream as they mature may make them candidates to naturally colonize upstream reaches. Anderson (1997) recommended that appropriate habitat was available in this reach far reintroduction of both Colorado pikeminnow and razorback sucker. Recently, both fish species have been stocked in this reach. Two hundred forty six juvenile (estimated mean total length [TL]= 200 mm; estimated range 165-230 mm), domestic-reared Colorado pdceminnow were 2