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Recovery Criteria When the following criteria have been met, the short-term goal will have been met: 1. Decline of the extant stock of the razorback sucker in Lake Mojave, Arizona and Nevada, has been reversed by management action, and the population reaches a sufficient size that genetic diversity is protected. The target size is 50,000 or more adult fish, and this abundance must be maintained or exceeded by natural recruitment for at least 5 years. 2. Management actions result in a razorback sucker population size of 5,000 adult fish in the lower Yampa-middle Green river stocks, with adequate numbers of naturally- recruited immature fishes to sustain this target adult population size for 5 years. 3. Management practices must be developed and instituted to improve biological (adverse nonnative fish interactions) and physical habitat conditions (e.g., flow regime, temperature, turbidity) to prevent further degradation habitats used by the populations listed under criteria 1-3. Because of ongoing studies of the razorback sucker, population objectives stated for the short-term goal will be reviewed periodically and modified as needed for recovery of this species. After the short-term goal has been achieved, down listing of the species may be considered when the following conditions are met: 1. Management actions result in a razorback sucker population size of 2,000 wild- produced adult fish in the lower Green River, with adequate numbers of naturally- recruited immature fishes to sustain the target adult population size for 5 years. 2. One additional population is recovered or established in the upper basin and one additional population is recovered or established in either the upper or lower basin. 3. All three of these additional populations shall reach a sufficient size to maintain genetic diversity and to be relatively secure from potential threats (to be determined by USFWS with advice of the Colorado River Fishes Recovery Team) and they shall receive legal protection necessary to insure their long-term survival. These populations must equal or exceed and identified threshold size for at least 5 years by means of natural recruitment. On the basis of critical habitat information, promising areas in the lower basin may include the Salt River (RZ14) and the Verde River (RZ15). Promising areas in the upper basin may include the Colorado (RZ7), Gunnison (RZ6), and San Juan (RZ9) rivers. After the species has been down listed to threatened, delisting of the species may be considered when the following conditions have been met: 36