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in the upper basin will be assessed and monitored using appropriate methods such as electrophoresis for protein analyses and restriction enzyme analysis for DNA. Other criteria such as geographic distribution, relative abundance, identified spawning sites, migration, and movements between stocks will also be used to identify and characterize stocks. In ' some cases, morphology may be useful in identification and characterization of stocks. ' All proposed stocking activities (i.e., experimental, augmentation, or restoration stocking) in the upper basin will be conducted as experiments that can be thoroughly evaluated to ensure that stocking will not disrupt the genetic diversity of remaining wild stocks and to assess the potential success of stocking. Habitat enhancement activities will be implemented before or in conjunction with stocking and will also be conducted as experiments to evaluate the responses of all fish species. These actions are necessary to prevent hybridization or introgression among and within similar species and to minimize competition and predation by nonnative fishes on the endangered fishes. It is especially important to limit experimental stocking of captive- reared endangered fishes to evaluate the benefits of stocking and to avoid potential adverse affects on genetic diversity of wild stocks (Kapuscinski et al. 1993; Philipp et al. 1993; Riggs 1990). Lichatowich and Watson (1993) emphasized that stocking of captive-reared endangered fishes may be a useful management tool but should not be used as a substitute for the protection and restoration of habitat to reestablish viable wild populations. They state that management emphasis on existing stable wild stocks of endangered fishes should be directed primarily on protection, preservation, and enhancement of natural habitats needed by various life stages to increase the numbers of fish that are needed for recovery. B. Declining Stocks. A systems approach (Box 3) will be used for (1) inventory and scoping (i.e., assessment) of available information and identification of issues or problems, (2) strategic planning for establishing measurable objectives, determining possible solutions to the issues or problems, reviewing opportunities for genetics management, and evaluating the potential genetics risks, (3) operational planning to implement necessary actions, and (4) methods for evaluation to determine the degree of success or to make necessary refinements. Factors that may be limiting numbers of the endangered fishes should be identified and actions taken to remove or significantly reduce the factors that caused population declines to achieve the overall goal of recovery. Emphasis will be placed on natural propagation of wild endangered fish stocks so that they can become self-sustaining. The relationship of captive propagation and stocking to natural propagation is outlined in Figure 1. All captive-reared fish for experimental, augmentation, or restoration stocking will be propagated using procedures outlined in Section V "Genetics Management of Captive Stocks" to maintain genetic diversity that is similar to the wild stock used as founders of broodstocks. 13