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<br />A <br />DTTRODUCTION <br />Establishing quantifiable objectives is critical for the management and recovery of endangered <br />species. Nonetheless, this task has eluded and perplexed biologists for decades. The United <br />States Fish and Wildlife Service (USFWS) has stated that the goal of recovery is to attain some <br />level of long-term population viability (USFWS 1990). Population viability is generally <br />determined by the numbers, densities, and distribution of individuals based on species-, location-, <br />and time-specific criteria, set at an "acceptable" level of risk, to ensure long-term survivorship <br />(Gilpin and Soule 1986, Schonewald-Cox 1983). However, from a review of 314 recovery plans <br />covering 344 species, Tear et al. (1995) found that only 18 species had recovery goals based on <br />both population size and number of populations. Approximately 5% (17) of the species had <br />recovery goals based on historical population numbers or population size. Other objectives listed <br />in the plans provided little management direction. Six broad categories were defined for over <br />901/o of the species. These categories were generally recovery actions rather than recovery <br />objectives: research, habitat protection, population maintenance, limiting factor abatement, habitat <br />management, and protective regulations. Additionally, the time-frame necessary for down-listing <br />and de-listing were stated for less than 20% of the species. Specific dates to achieve these targets <br />were proposed for only 9% of all species. These statistics reflect the status of quantifiable <br />recovery objectives for endangered fish in the Upper Colorado River Basin (UCRB). <br />In the UCRB, four endemic fish species are federally listed as endangered: Colorado squawfish <br />(Ptychocheilus lucius), humpback chub (Gila cypha), razorback sucker (Xyrauchen texanus), and <br />bonytail (Gila elegans). The original draft recovery plan for Colorado squawfish written in 1978 <br />called for the development of quantifiable recovery objectives (USFWS 1991). Following the <br />establishment of the Upper Basin Recovery Implementation Program (UBRIP) in 1986, the need <br />for quantification of objectives for each species was reiterated. In 1992, Nesler (unpublished <br />report) made the first attempt to develop quantifiable recovery objectives for these species within <br />the State of Colorado. Gilpin (1993) conducted a population viability analysis of Colorado <br />squawfish. The current recovery plans for all four endangered Colorado River fish, however, <br />have yet to include quantifiable objectives (USFWS 1990, 1991, 1996). <br />The lack of sufficient information on species habitat needs, population genetics, population <br />demographics, and other population characteristics has been a primary factor preventing the <br />establishment of sound quantifiable objectives. Tear et al.'s (1995) review provided a good <br />summary of the types of information that have been used to establish recovery objectives and <br />deficiencies in the collection of that information. Of the 314 recovery plans reviewed, they <br />indicated that 78% of the 344 species addressed lacked sufficient population information (Table <br />1). Specific information, such as dispersal, effective population size, and survival rates, was <br />generally known for less than 6% of the species. Temporal variation estimates for fecundity, age <br />structure, and survival was essentially unknown for all species examined. The most readily <br />available information included patterns of distribution. Similar levels of information are available <br />for endangered Colorado River fish (Table 1 and below). <br /> <br />