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plans. By the mid-1980's it became increasingly evident that the scope and resources needed for restoration had to be expanded. The Recovery Program for the Endangered Fishes of the Upper Colorado River started in 1988 as a IS-year, multiagency program to re-establish self-sustaining populations of razorback sucker, humpback chub, bonytail chub, and Colorado squawfish, while providing for future water development in the upper basin. Participants include 14 state and Federal agencies, water user groups, and environmental organizations. The program is attempting to improve reservoir withdrawal patterns to better mimic historic pre-dam hydrographs, to remove or mitigate migration barriers, and to allow for some natural flooding which is deemed critical for inundating historic nursery habitats. Levees are being removed or breached to reconnect historic flood plain nursery habitats. The program is also purchasing water to insure adequate flows, buying and protecting critical floodplain habitats and developing management guidelines to reduce the impact of non-native fishes. The program has and continues to fund excellent research and has a superb public awareness program. Information about the plight of these fish and the importance of protecting the river's ecosystem is presented through public meetings, brochures, newsletters, scientific conferences, and public television. Initially, the cost to recover these fish was estimated at US$40 million, however, later estimates were revised to US$150 million (USFWS 1993). The IS-year program has entered its tenth year and while a great deal has been accomplished, there has been little or no improvement in the status of the four endangered fishes. Colorado squawfish and humpback chub populations remain low, wild razorback suckers have declined to critically low numbers, and wild bonytail chub is believed by many to be gone. It's quite doubtful that restoration will be realized within the program's IS-year time frame. Native Fish Work Group Approximately 98% of all wild razorback suckers are found in Lake Mohave, a 100 km long reservoir located immediately downstream from Hoover Dam. Davis dam was constructed in the early 1950's and its closure created a 11,500 hectare lake. The inundation of the river trapped razorback suckers and bonytail chub and early reservoir conditions greatly favored both natives. Newly flooded habitats were highly productive and in the absence of non-native fish predators, survival was high, allowing razorback sucker numbers to climb into the 100,000's. These conditions quickly changed as carp, black bass, sunfish, and other species were stocked, reproduced, and grew in size and number to a point where they could suppress sucker recruitment. No natural recruitment (i.e. juveniles) for either razorback sucker nor bonytail chub has been observed since the early 1960's. Population estimates made during the late 1980's and early 1990's showed the numbers of razorback suckers had declined nearly 60% from 1988 to 1992 (Marsh 1994). This decline was expected. Biologists had warned that old fish were nearing the end oftheir life span as old individuals rapidly began to die off. It was estimated that razorback suckers would vanish from Lake Mohave within the decade unless actions were taken to introduce young adults back into the population. Frustrated by the failure of restoration and stocking efforts elsewhere, local resource managers formed the Native Fish Work Group (NFWG), a multiagency coalition designed to prevent the extinction of the species in the lower basin. The NFWG recognized the resources (monetary, political, and technical) to recover the razorback sucker in Lake Mohave were not available, but something short of full recovery was desirable and quite feasible. A long- term, conservation management plan was developed with the goal of replacing the old, dying population with 50,000 young adults. The concept was to stock suckers large enough to insure their survival and the continued presence of the species for the next 3 to 4 decades. Past stocking programs had shown that survival was directly correlated to body size- the larger the fish, the greater its chances for survival. The primary question became, "how can large numbers of big fish be raised cheaply?". Existing hatchery space was fully utilized, costly when available, and the cost of constructing new facilities was prohibitive.