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16 native fishes, Also, some species of nonnative fishes eat the native fishes and this is believed to be a reason for the decline in native fishes, The Recovery Program has implemented nonnative fish removal efforts for small nonnative cyprinids and centrarchids from backwaters and other low velocity habitats, Removal efforts focus on trying to achieve a decrease in numbers of small minnows prior to spawning by Colorado pikeminnow, Some removal may need to occur during razorback spawning, Centrarchids snch as green sunfish and largemouth bass are predacious and impact endangered fish populations, These fish will be removed by contractors for the Colorado Division of Wildlife from low velocity habitats during the summer of each year for as long as needed to attain viable endangered fish populations, Other nonnative fish collected while targeting cyprinids and centrarchids also will be removed when encountered, The Colorado Division of Wildlife will prepare and adopt a Colorado River Fisheries Management Plan that will implement a more detailed nonnative fish control effort, The plan will be reviewed and approved by the Recovery Program and Colorado Wildlife Commission. The Plan will be finalized and implemented by the dates specified in the Recovery Action Plan, 5. Research, Monitoring, and Data Management Element Monitoring the status and trends in fish populations has been an integral component of the Recovery Program, An interagency standardized monitoring program was established in 1988. The ISMP was designed to annually measure the catch per unit of effort of humpback chub and Colorado pikeminnow at different life stages, Y oung-of-the- year Colorado pikeminnow are sampled by using a seine in backwaters (zero velocity habitat) in four large reaches of the Green and Colorado Rivers during the fall. Subadult and adult Colorado pikeminnow are sampled by electrofishing in 13 reaches of the Yampa, Green, White, and Colorado Rivers during April or May, Humpback chubs are monitored less intensively every 3 years in Black Rocks and Westwater Canyons of the Colorado River, Trammel nets are used in the early fall to sample subadultladults. More recently, ISMP has been expanded to estimate population sizes, A population estimate of Colorado pikeminnow in the upper Colorado River was around 600 adults in 1991-1994 (Osmundson and Burnham 1996); a preliminary estimate conducted in 1998 yielded over 700 adults (USFWS unpublished data), Preliminary population estimates for humpback chub are 1,500 adults in Black Rocks (Pfeifer et aL 1998) and approximately 7,000 adults in Westwater Canyon, A basin wide razorback sucker monitoring plan has been developed and will include reaches of the Colorado River coincident with augmentation of these populations, Monitoring will continue until the fish are delisted, The Service anticipates the implementation of the Recovery Actions will provide a positive population response for each species, Information from the ISMP will be used to determine population responses, Population status and trends will be determined by the population indicators outlined in Appendix D, The Recovery Program is currently developing recovery goals for the four endangered fish species, If a population meets or exceeds the recovery goals or the goals described in Appendix D for that species, it will be considered to exhibit a positive