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<br />2. To conserve genetic diversity of wild endangered fish stocks through recovery efforts that will <br />protect or restore viable wild stocks by removing or significantly reducing limiting factors that <br />caused population declines. <br />3. To maintain genetic diversity in captive-reared endangered fishbroodstocks that is similar to the <br />wild stock used as founders. <br /> <br />Stock Identification and Characterization of Stocks in the Upper Colorado River Basin <br /> <br />Eleven presumptive stocks of endangered fishes were identified in the Upper Colorado River Basin from <br />ecological data: 3 for razorback sucker, 5 for humpback chub, and 3 for Colorado squawfish. A stock of <br />bonytail was not identified in the upper basin because captures are very infrequent and widely distributed <br />without an identified spawning site. <br /> <br />A Work Group from the Biology Committee will convene in the March 1998 to review available <br />infoOllation related to identification and characterization of endangered fish stocks in the Upper Colorado <br />River Basin. The status and trends of these presumptive stocks will be reviewed and priorities for <br />propagation deteOllined by species and stocks within species (Biology Committee Meeting 1/15/98). <br />Species priorities will be assigned on the basis of status and trends. <br /> <br />Priorities for Management Actions <br /> <br />The priorities for management actions will be deteOllined by the Work Group and based on species, stocks, <br />status and trends of the stocks, availability offacilities, and urgency for captive propagation. <br /> <br />IV. Goals, Objectives, End Product: <br /> <br />Goal: To construct propagation facilities to serve as primary and backup refuges and as growout facilities <br />for priority endangered fishes for the Recovery Program in the Upper Colorado River Basin. <br /> <br />Objectives: <br /> <br />]. To select suitable sites as propagation facilities for genetic refuges, broodstock development, and <br />production for research and development as well as experimental, augmentation and restoration stocking <br />in the Upper Colorado River Basin. <br /> <br />2. To plan, design, and construct propagation facilities for captive-rearing of endangered fishes for the <br />Upper Colorado River Basin. <br /> <br />3. To conduct experimental stocking of razorback sucker in the Upper Colorado River Basin to deteOlline <br />(l) the dispersal of stocked fish, (2) survival by size of fish at release, (3) habitat use of juvenile and <br />subadult fish, (4) best sampling gear to sample juvenile and subadult fish, for future monitoring, (5) time <br />of year to release fish, (6) location of release, (7) need for.physical conditioning prior to release into a <br />riverine environment, (8) need to alter behavior so that fish can adapt to foods in rivers, (9) interaction <br />with nonnative fish species, and (10) the role of imprinting to fidelity in spawning sites. <br /> <br />4. To conduct experiment reintroduction stocking of razorback sucker and bonytail to deteOlline the <br />relation of survival to size at stocking and the importance of physical conditioning (i.e., flow training) to <br />survival. <br /> <br />End Product(s): <br /> <br />Propagation Facilities: Primary refuges, backup refuges, grow-out ponds, and production facilities. <br /> <br />Captive-Reared Endangered Fish: Broodstock development, refuge to prevent catostophic loss (i.e., <br />extinction of specific stocks), and fish for augmentation. <br /> <br />V. Description of past perfonnance on this or similar projects: <br /> <br />Propagation of the endangered Colorado River fishes began in I 987'with the construction of some small <br />ponds on the Ouray National Wildlife Refuge to produce fish for experimental stocking. This site was <br /> <br />OS/22/98 <br /> <br />3 <br />