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aforementioned experimental stocking plans. These plans were intended for initiating a comprehensive restoration stocking program aimed at establishing naturally sustaining populations. They were also more specific than earlier experimental stocking plans and met the goals and objectives set forth by the Genetics Management Plan (Wydoski 1995; Czapla 1999) and the Endangered Fish Interim Management Objectives (IMO's) for the RP. These stocking plans provided direction and rationale for initiating and conducting propagation, augmentation, and restoration for razorback sucker in select rivers within the Upper Colorado River Basin in each of the respective states. The plans also included priorities among the four different endangered fish species and river reaches, genetic risk assessment, size and number of fish to stock over a period of 5 to 9 years, time of year to stock for best survival, and criteria for contribution to recovery success as well as expectations and limitations. Both Colorado (Kesler 2001) and Utah (Hudson 2001) revised their former plans to be consistent with population abundance criteria developed within the recovery goals for razorback sucker (FWS 2002) and the other three endangered fish species in the Upper Colorado River Basin. These two revised plans identified stocking targets over the next 8 to 10 years based on the criteria in the recovery goals and integrated survivorship estimates (see Ryden 2001). These criteria replaced the previous objectives identified in each of the two plans based on the IMO's. The primary goal identified in these stocking plans was to establish at least one to three minimum viable razorback sucker populations (5,800 adult fish from ages, 5 to 7) in the Upper Colorado and Gunnison rivers in Colorado to complement the existing razorback sucker populations in the middle and lower reaches of the Green River in Utah. Utah's plan identified establishing one minimum viable population in the Green River (5,800 fish of a multiple age-class structure). These revised stocking plans called for the production of fewer, but larger razorback sucker than earlier versions, and considerably less fish than requested for this evaluation. The Colorado stocking plan for razorback sucker called for producing a 300-mm, domestic-reared razorback by the age of 2 + before stocking into the mainstem Colorado and Gunnison rivers in Colorado. In November 2002, an integrated stocking plan was formulated that served as an addendum to the previous stocking plans developed by Colorado (Kesler 2001) and Utah (Hudson 2001). The integrated plan (Nesler et al. 2002) unified the separate State stocking plans and included the San Juan River subbasin; the intent 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 years. Unchanged was the survival 5