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4) Successful reproduction and self-sustaining status will necessitate the presence of adequate distribution and amounts of nursery habitat in flooded bottomlands or backwaters maintained by a natural flow regime and favorably enhanced by nonnative fish control activities. Further, the following species interactions and recovery actions are assumed/anticipated: I) Razorback sucker biomass increase above 5 % may cause reduction in biomass of flannelmouth sucker due to more similar low-velocity habitat use and potential competition. 2) Biomass and production of common carp, white sucker and other nonnative species may be reduced by control efforts, therefore reducing competitive pressure upon sympatric native suckers, and perhaps facilitating expansion of razorback sucker beyond the 5 % target biomass. 3) With successful establishment of an adult razorback sucker population, general abundance of other native species may be reduced as a result of some competition. Reach priorities were based on the following considerations: 1) The Colorado River (Rifle to Debeque) and Gunnison River reaches are higher priority than the Palisade to Stateline reach of the Colorado River due to the higher relative abundance of native fishes in general and native suckers in particular, and the lack of an abundance of large predaceous fish species; suggesting a more favorable environment for survival. 2) Concentrations of selenium that may impact razorback sucker reproduction adversely via survival of larvae appears to be greater in the Gunnison River reach, making the upper Colorado River reach potentially more favorable for reintroduction, and ultimately, successful reproduction and survival of young razorback sucker. Stocking Plan... Bonytail (Table 2) Bonytail are considered the second highest priority for stocking, but only due to the high value of expanding the genetic material remaining in the few, viable stocks of razorback sucker left in the wild. Bonytail are functionally extiIpated in the wild and restoration stocking of progeny from the remaining captive stock is the only recourse for re-establishing populations. The source for bonytail to be stocked will be from the captive broodstock currently being held at Dexter National Fish Hatchery. These fish were progeny from 10 artificially-spawned bonytail captured from Lake Mohave (Minckley et al. 1989). No further infusion of new genetic material is anticipated due to the extreme rarity of captures of viable bonytail from anywhere in the basin. Current recovery strategy for this species is to prevent its immediate extinction. Maintenance of the captive broodstock at Dexter National Fish 8