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VI. PRIORTTIES FOR PLACING ENDANGERED FISHES IN GENETIC REFUGES OR DEVELOPING BROODSTOCKS Priorities for holding endangered fish in refuges or for development of broodstocks for captive propagation were discussed and established by the Biology Committee based on available knowledge of their status and trends and potential risks of extinction (Table 2). These priorities are summarized in Table 3 by species and by stocks within species. Priority 1 is the highest priority and priority 4 is the lowest. Species priorities have precedence over stock priorities for propagation of placing fish in refugia. Priorities for species were based on status and trends from the Interagency Standazdized Monitoring Program (McAda et al. 1994) and catch-per- unit-of--effort from research efforts. Species priority was based on status and trends of the stocks as determined from catch per unit or effort; stock priority was subjectively determined by considering historic abundance and distribution, identified spawning sites, recruitment, and the probability of the stock being extirpated in the wild. With species and stock priorities established, the Biology Committee made decisions ("yes/no"} regarding the need to place a particulaz stock into a refuge and develop broodstock. Table 4 reflects the decisions made by the committee over several meetings. Recognizing that the stocks of razorback sucker aze continually declining the decision was made to concentrate an effort on developing the broodstock for the Green and Colorado rivers. Restoration plans for bonytail require the development of broodstock. With an augmentation plan for Colorado pikeminnow in the upper Colorado River, refugia and broodstock may be necessazy. The committee decided it was not necessazy at this time to place the other stocks of Colorado pikeminnow and all the stocks of humpback chub in refugia or develop broodstock. Razorback Sucker: As a species, razorback sucker aze considered the highest priority within the Recovery Program because of recent and continued population declines combined with low recruitment and poor spawning events. Middle Green River This stock was assigned the highest priority of"1"because the Middle Green/Yampa River stock contains approximately 500 adult fish as of 1993 and appears to be declining with an estimated 80% survival annual rate. Lack of recruitment and few numbers of spawning adults has been indicated by a lower catch-per-unit-effort and estimated population size. Lower Green River This razorback sucker stock was assigned priority "1"because all stocks may be important in the recovery effort. Upper Colorado River This stack was designated as priority "1" because of the rapid decline and precarious status. Few wild razorback suckers have been caught in recent years. Augmentation stocking events have had limited success demonstrating poor survival. Bonytail: The bonytail is neazly extirpated in the upper basin (Maddox et al. 1993; U.S. Fish and Wildlife Service 1990x). Only occasional individuals are captured very infrequently (i.e., years between captures). Broodstocks have been developed from Lake Mohave stock for restoration stocking in the upper basin. This species was assigned Priority " 2" because it is neazly extirpated from the upper basin and broodstocks for restoration stocking will be developed from bake Mohave stock. t 14