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<br />002828 <br /> <br />propagation are presented in Tables 1-3 for each species and river reach described by fish size <br />and year stocked, It is proposed that restoration stocking is desirable for three of the endangered <br />Colorado River fishes (listed in priority): razorback sucker, bony tail, and Colorado squawfish, <br />Table 4 provides the survivorship curves used to back-calculate from the target numbers <br />proposed as an objective for each species to determine numbers offish needed at each age/size, <br />These survival rates and fish sizes were estimated in Wydoski (1996). for a hatchery <br />environment, and therefore, may underestimate numbers of fish needed to meet stocking <br />objective endpoints. The goal of stocking for each species is the establishment of a multi-year- <br />class population of a desired abundance level (fish/mile). Stocking would be continued annually <br />until the multi-year-class composition and abundance criteria were met. <br /> <br />This stocking plan will require the propagation of 1.1 to 5.2 million fish per year for <br />the first five years if propagation of all three species is ,begun simultaneously. The plan will <br />result in the propagation of about 12,8 million razorback sucker, 2,6 million bonytail, and <br />720,000 Colorado squawfish, or almost 16,2 million fish total, These fish would be raised over <br />a seven year period, Table 5 represents a summary of fish numbers needed and fish on hand <br />by species, size, and year in order to meet stocking goals, For razorback sucker, stocking is <br />proposed for two reaches of the Colorado River from Rifle to Debeque and Palisade to Stateline, <br />and in the Gunnison River from Hartland Dam to Redlands Dam. For Colorado squawfish, <br />stocking should occur in three rivers-the Colorado River from Rifle to Debeque, the Gunnison <br />River from Hartland Dam to Redlands Dam, and in the Dolores River from Disappointment <br />Creek confluence to Stateline. Bonytail will be stocked in the Yampa River in Dinosaur <br />National Monument and in the Colorado River within the Grand Valley reach. <br /> <br />For all three of these species, the stocking of different sizes of fish in two seasons is <br />proposed to evaluate the relation between size of fish released and season stocked with survival, <br />and determine the most effective combination for subsequent propagation .and stocking plans, <br />The approach described here is to stock two sizes of each species for three years in both the fall <br />and spring seasons in each target river reach. For razorback sucker and bony tail, the two fish <br />sizes represent the estimated size of fish after the first and second growing seasons, For <br /> <br />DRAFT - June 4, 1997 <br /> <br />4 <br />