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extinction of a species or stock of endangered fishes. They also provide a genetically viable source for augmentation and restoration stocking efforts that will be made in the Upper Basin. This alternative was dismissed because captive propagation is an integral part of the Recovery Program in developing broodstocks that will be maintained in refugia to meet recovery needs of endangered fish for research, information and education programs, and stocking. 3. Stock Suralus Endangered Fish into the Upper Colorado River Basin. The Program's "Genetics Management Guidelines" provides precautions, procedures and strategies to prevent genetic risks in propagation (Williamson and Wydoski 1994). This document also identifies breeding strategies that will maximize the effective population size of captive fish used to develop broodstocks. Genetic conservation of the endangered fish stocks in the Upper Basin will be accomplished by following procedures in three documents: Genetics Management Guidelines, Genetics Management Plan, and Stocking Plans. The "Genetics Management Guidelines" provide a conceptual framework for genetics management and rationale for maintaining genetic diversity of wild and captive endangered fish stocks in the Upper Colorado River Basin. A "Genetics Management Plan" will identify and characterize endangered fish stocks in the upper basin, determine status and trends, and establish priorities for effective and rational genetics management by species and stocks within specific river reaches. Finally, "Stocking Plans" for specific actions will include the justification and rationale for stocking and other details such as species, size of fish, timing of release, location of release, genetic risks, and a description of how the evaluation of the stocking will be made. Stocking plans must be approved by the Program and must be covered by a Federal Fish and Wildlife Permit. A Section 7 consultation under the Endangered Species Act may be required to determine if the proposed stocking may jeopardize wild stocks of endangered fish in the upper basin. Stocking of endangered fishes into their historic range should be done in a genetically and ecologically sound manner to prevent genetic swamping of the wild gene pool and to ensure that only fish with attributes that will survive in waters that are targeted for stocking. The philosophy of the Recovery Program is to maintain the genetic integrity of wild and captive-reared endangered fishes in the Upper Colorado River Basin to prevent irreversible losses of genetic diversity that may result from management interventions or lack of action (Williamson and Wydoski 1994). Standard fish hatchery practices are not suitable for recovery of endangered fishes because the genetic integrity of the captive-reared fish stocks may be compromised and result in (1) extinction of a species or stock, (2) loss of genetic diversity within stocks or populations, (3) loss of genetic diversity among stocks or populations, and (4) inadvertent artificial selection (Kapuscinski et al. 1993).