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1 interim report on available genetic analyses (i.e., electrophoresis ' and morphology) in the Gila species will be completed in 1995. The final report on the Gila species, including mtDNA analysis, is scheduled for completion in 1997. ' B. Procedures for Reviewing Stock Identification and Characterization. Members of the Program's Biology Committee and an Ad Hoc panel of fishery geneticists will periodically review presumptive stocks of endangered ' fishes in the Upper Colorado River Basin as new information becomes available on distribution, behavior, migrations, movement (i.e., interchange between stocks), phenotypic information, and genetic information. Even with the available criteria for stock identification and characterization, the present ability to evaluate and classify stocks is not perfect. Therefore, all stocks will be treated separately (i.e., using a conservative approach) until future information indicates ' otherwise because all wild stocks may be important in the recovery effort. ' C. Criteria for Determining Status and Trends of Endangered Fish Stocks. The determination of status and trends among various endangered fish stocks is imperative for making informed management decisions (Philipp et al. 1986). Decisions on actions regarding endangered species must be ' made on a case-by-case basis using standard criteria (Rolf 1991). The status or trends of presumptive endangered fish stocks in the upper basin is determined by: 1. Monitoring the distribution and relative abundance of presumptive stocks by species, ' 2. Documenting spawning and recruitment, 3. Identifying the potential for extinction from catastrophic risk, and 4. Estimating the probability for immediate extinction. Distribution and relative abundance of Colorado squawfish in the upper basin and humpback chubs in Black Rocks and Westwater Canyons are determined through an ongoing Interagency Standardized Monitoring Program ' (McAda et al. 1993). Data on the present relative abundance of razorback sucker and nonnative fishes are also obtained through the monitoring program. In addition, other ongoing field studies also provide vital ' information on status and trends of the endangered fishes that supplements data from annual monitoring. D. Procedures for Monitoring the Status and Trends of Endangered Fish ' Stocks. The status and trends of endangered fish stocks in the Upper Colorado River Basin will be reviewed annually by members of the Program's Biology Committee and other interested persons. Changes in ' status and trends will be made from new information on the stocks from the monitoring program and other field studies. E. Priorities for Placing Endangered Fish in Genetic Refugia or Developing ' Broodstocks. Assignment of priorities involves a judgement call but is based on hard data (i.e., objective information) such as relative abundance of fish, size distribution, and documented recruitment as well 1 9