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protocol for paired matings of broodstock to ensure that genetic diversity is protected and maintained. Selection of stream reaches for stocking razorback sucker will be determined from known collection sites over the past 17 years as well as criteria and recommendations developed from past and future habitat suitability studies. Studies to identify suitable habitat will aid in determining specific locations for experimental stocking. Until these studies are completed, the general areas recommended for initial experimental stocking in the upper Colorado River drainage include 1) the Grand Yall ev near Grand Junction, 2) Rifle to Dba4ue, and 3) the Gunnison River nP&r Delta, Colorado upstream of Redlands Diversion Dam. Habitat development and enhancement of natural and man-made riverine features will assist in the recovery of razorback sucker in the upper Colorado River. Restoration of wetland habitats adjacent to the river corridor that historically flooded but no longer become inundated during the late spring and early summer may be an important factor in the reestablishment of self- sustaining razorback sucker populations in previously occupied river reaches. Larval razorback sucker may need access to productive wetland habitats during the late spring period when they are drifting downstream immediately following spawning. Determining and establishing spring flows sufficient to inundate wetland habitats adjacent to the river to allow access for larval razorback sucker may be very critical to the ultimate recovery of this fish. Man-made levees that block natural river features such as oxbows should be modified to allow fish access during runoff. It would be valuable to implement recommended river flows that would enhance habitat for all life stages of razorback sucker and subsequently evaluate the effect of these flows on razorback sucker populations. Progeny artificially propagated from wild broodstock collected from the upper Colorado River, would be individually marked with PIT tags at the hatchery at a length of about 100 mm to 125 mm and later transferred to grow- out ponds where they would be reare to the desired size before being released into the river. Initially, either large juvenile or adult razorback sucker (250 to 300 mm total length) would be stocked in the upper Colorado River in early spring. Approximately 10 to 20 fish. each equipped with radio transmitters, would be released at each stockino site. Systematic biological monitoring and evaluation of stocked fish would be conducted to obtain biological information from experimental stocking. A monitoring program would include the assessment of potential genetic impacts released fish may have on wild fish stocks within and beyond the area of directed activity. Standard, quantitative surveys would be performed annually for stocked fish. Captured fish would be checked for PIT tags. Recaptured fish would provide information on survival, movement, post-stocking dispersal, and age and growth information useful in development of aging techniques for wild fish. Verification of successful spawning and recruitment would be conducted annually by sampling in and around suspected spawning areas and downstream reaches following the suspected spawning period. V D