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<br />002775 <br /> <br />BackuD Refuges: Backup refuges are intended to maintain priority endangered fishes to prevent <br />catastrophic loss and to backup broodstock fish and fish held for long-tenn research experiments. <br />Two refuges are needed as backup to Ouray and Grand Valley. The most cost effective solution for <br />a backup refuge is simply to maintain the fish in ponds with a reliable water supply in a secure area. <br />Such ponds should have a sloped bottom and a fish trap at the outlet to provide easy access to the <br />fish. Some interest has arisen to allow the Green and Colorado Rivers to serve as the backup refuge <br />rather than supporting an additional facility or acquiring ponds. <br /> <br />Grawaut Ponds: Excellent growth of razorback suckers, bonytail, and Colorado squawfish has been <br />realized in riverside ponds of the Upper Basin (Osmundson 1986; Osmundson and Kaeding 1989). <br />Endangered fish that are propagated in natural ponds should more closely exhibit the feeding and <br />predator avoidance behavior of wild fish and should experience better survival after being stocked <br />into the Upper Basin. Therefore, growout ponds will probably be the preferred option for rearing <br />endangered fish to be stocked into Upper Basin waters. The actual area of growout ponds needed <br />has not yet been detennined because stocking plans have yet to be finalized for all river reaches. <br /> <br />4.0 Genetic Surveys of Endangered Fish Species <br /> <br />The purpose of genetics management within the Recovery Program is to maintain the genetic integrity <br />of wild and captive-reared endangered fishes in the Upper Colorado River Basin to prevent <br />irreversible losses of genetic diversity that may result from management interventions or lack of action <br />(Williamson et al. 1994). In support of this mission, three genetic surveys were initiated including <br />(1) genetic survey of.Gila complex, (2) genetic survey of razorback sucker, and (3) genetic survey <br />of Colorado Squawfish. The accomplishments and status of these surveys are discussed in the <br />following sections. <br /> <br />4.1 Genetic Survey of Gila Complex <br /> <br />Recovery of humpback chub (.Gila ~) and bonytail chub (.Gila eleilans) has been thwarted by <br />uncertainty about the taxonomy of species in the genus .Gila (bonytail, humpback, and roundtail <br />chubs). In 1989, a Project Manager was hired from the Smithsonian Institution to review existing <br />genetic information related to the .Gila complex, to develop a data collection and sampling protocol, <br />and to develop a detailed work plan of study needs. A draft report entitled "Review of Existing <br />Infonnation on Taxonomy and Distribution, Activities of Researchers, and Collections Resources for <br />Fishes of the Cyprinid Genus Gi!.a from the Colorado River Basin" was submitted in 1990 (US. Fish <br />and Wildlife Service 1990c). This report contained a detailed review of the existing knowledge base <br />regarding the .Gila species. <br /> <br />The Genetics Panel (Section 3.1. I) was assigned an oversight and advisory role during the planning <br />and execution of the .Gila genetics project. A report entitled "Management Concerns, Priority <br />Research Needs, and Proposed Research Plan" for the .Gila complex was submitted to the USFWS <br />in early 1990. Later in 1990, contracts were awarded to perfonn research in three areas of genetic <br />significance: (1) morphological characteristics. (2) allozyme analysis, and (3) mitochondrial DNA <br />analysis. Each of these areas is described below. <br /> <br />15 <br />