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.i 'I 396 Recovery of Long-lived Species version Dam on the Gunnison River. The lower Gunnison was historical habitat for Colorado squawfish, and the USFWS wished to evaluate the feasibility of retrofitting the dam with a passageway as a means of reestab- lishing connection with parts of its range. The work was placed on hold because of the pro- jected high cost of the structure and a lack of convincing arguments that the fish would use it. Extirpation of squawfish from the lower Colorado River basin was almost certainly caused by habitat alterations. It is therefore somewhat alarming to encounter assump- tions that further alterations would be helpful to viable populations. Attempts to provide new, better, or more productive aquatic habi- tats must be approached with caution because they may result in the opposite effect. The "Frankenstein effect" (Moyle et a!. 1986)- immediate and local solutions to a problem that cause adverse effects over a long-term or widespread scale-is a possibility that must be avoided. In the case of Colorado River fishes, a narrow species (or life stage) approach may well have negative effects on other species or life stages of the same species. Far too often habitat improvement projects have been ill planned, politically expedient approaches to management, with lit~le or no follow-up or project maintenance (Rinne and Turner, this volume, chap. 14). Provision of new or improvement of exist- ing habitats can only be successful if strict ecological principles are applied. This chal- lenge is recognized in the RIP, and the follow- ing stipulations are to be met (USFWS 1987a) before habitat development and management studies occur: (1) testing and implementation of management techniques will not be con- ducted in confirmed spawning and nursery areas, or in river reaches in which modifica- tions might adversely affect use of confirmed spawning or nursery areas; and (2) genetic in- tegrity of wild populations must be protected :;:'.~L,,; when using hatchery-reared animals. There ii,' are obv~ously .other stipulations that could be ....:.~.. added, mcludmg a need to develop adequate '~ follow-up and provide for maintenance of}\:' habitats that are developed. Also, delineation and protection of sensitive areas (USFWS 1987a) demand further attention relative to criteria for their formation and the types of protection afforded. Stocking Rare Fishes Stocking for recovery of squawfish has not occurred in the main-stem Green River be- cause there is a naturally reproducing popula- tion there. Some stocking has been performed in Kenny Reservoir on the White River, Colo- rado, in an experimental attempt to establish a sport fishery. Colorado squawfish also have been stocked in other locations, including the upper main-stem Colorado and in the lower basin. Squawfish stocked in the upper main-stem Colorado River included 1474 six-year-old fish, planted in 1980 (Valdez et a!. 1982b) and tagged with Carlin dangler tags. Seventeen were recaptured in the last eight years. About 76,000 age-o fish (50-125 mm n) were also stocked between 1982 and 1984 (Kaeding, USFWS, pers. comm.). An additional 71,576 were stocked in streamside ponds in 1983 and 1984, and an undetermined number escaped into the Colorado River as a result of high water (D. Osmundson, USFWS, pers. comm.). Reintroduction of squawfish into parts of the lower basin from which they had been extir- pated was initiated in 1985 by the Arizona Game and Fish Department and the USFWS (1989a). More than 100,000 fish, fingerlings through adults, have been stocked into the Salt and Verde rivers, and some have been re- captured (Brooks 1986b; Hendrickson and Brooks 1987). The relative success of all these introductions needs more evaluation. Stocking can benefit management for recov- ery, but only in a comprehensive program in