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(Wydoski 1994a). Propagation facility needs fall into three major categories (Wydoski 1995) that include primary refuges, backup refuges, and growout ponds. A. Primary Refuges. Primary refuges are intended for developing and maintaining broodstocks and for production of endangered fish for priority research experiments. The propagation facilities at these refuges should be able to rear pedigreed family lots of fish. Two primary refuges were identified for broodstock development. The Ouray Endangered Fish Facility will be used for Green River stocks and the Grand Junction Endangered Fish Facility (Hatchery Building and Horsethief State Wildlife Area ponds) will be used for Upper Colorado River stocks. The Middle Green River razorback sucker broodstock is intended to serve as a safeguard to maintain the genetic diversity of that stock while recovery efforts are directed at increasing survival of larvae from natural propagation (Williamson and Wydoski 1994). This broodstock can be viewed as an "insurance policy" to prevent the possible extinction of the wild stock as adults are lost through natural mortality. The Upper Colorado River stock of razorback suckers has declined so that few adult fish are captured during monitoring and sampling associated with other studies. In some years, no razorbacks are captured. Therefore, broodstock development of this stock and experimental reintroduction stocking will be required to re- establish a population in the wild. Backup Refuges. Backup refuges are intended to maintain priority endangered fishes to prevent catastrophic loss, backup broodstock fish, and fish for long-term research experiments. Two refuges are needed as backup to the Ouray Endangered Fish Facility and the Grand Junction Endangered Fish Facility. A backup refuge for Green River stocks will be maintained at the Craig Municipal Facility in Colorado. A site will be selected for the Upper Colorado River in the near future. The most cost-effective solution for a backup refuge is simply to maintain the fish in ponds with a reliable water supply in a secure area. Such ponds should have a sloped bottom and a fish trap at the outlet to provide easy access to the fish. C. Growout or Production Ponds. Excellent growth of razorback suckers, bonytail, and Colorado squawfish was realized from predator-free off-channel lagoons or impoundments in the lower basin (Mueller et al. 1993; Mueller 1995) and in riverside ponds of the upper basin (Osmundson 1986; Osmundson and Kaeding 1989). Endangered fish that are propagated in natural ponds should more closely exhibit wild fish behavior in feeding or predator avoidance and should have better survival after being stocked into the upper basin. Therefore, growout ponds will be used for rearing endangered fish to be stocked into upper basin waters. The actual 4