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After nearly two years of deliberation and review, a working group of program scientists reached agree- ment on a framework for floodplain restoration that recognized that the augmentation of fish populations in grow out ponds would be conducted under another program element (discussed next). A set of hypotheses about the natural function of floodplain habitat and about the response of non-native fishes to the restora- tion of such habitat will be initially tested by: selecting floodplain sites from a comprehensive inventory of the Upper Basin, acquiring access to such sites, reconnect- ing them to the river by removing levees, and monitor- ing the response of both native and non-native fishes. The method is to re-connect selected floodplain sites sequentially and compare the biological response in similar, naturally occurring habitats. Some hypotheses will also be tested at more controlled floodplain sites to which the program already has access. Fish refugia and population augmentation A major element of the Upper Basin Program is to bank genetic stocks of the listed fishes in refugia, and to experiment with the artificial augmentation of wild populations and re-stocking. One threshold issue was what stocks should be placed in refugia and managed as broodstock, before a series of studies confirming their genetic distinctions were completed. Twelve "pre- sumptive" stocks of the squawfish, humpback and razorback were conservatively identified in the Upper Basin based on their geographic distribution, move- ment, and spawning sites (no presumptive bonytail stock was identified in the Upper Basin because it is so rare if not extirpated in this basin); guidelines for man- aging the genetic diversity of captive and wild stocks were peer reviewed and accepted; and a "hatchery" facilities plan was developed from an initial prioritiza- tion of the needs for captive broodstock and popula- tion augmentation. The amount of artificial 54 propagation and augmentation needed to stabilize or recover populations of listed fishes in the Upper Basin is not known, is related to habitat restoration and the management of non-native fishes, and is being approached experimentally. The construction and expansion of two primary refu- gia for the listed fishes - one for the Colorado River subbasin, and one for the Green River subbasin, along with a set of back-up refugia and low cost grow out ponds, are now underway. Adaptive plans have also recently been approved and undertaken for the aug- mentation of the razorback population on the Green River, for the re-stocking razorbacks on the upper Colorado River and Gunnison Rivers, and for re-stock- ing bonytail chub on either the Colorado or Green Rivers. Management of non-native fishes The management of non-native fishes that prey on and compete with the listed fishes is considered to be as fundamental an element of the Upper Basin Program as flow protection, other habitat restoration, and population augmentation. A cooperative federal- state procedure for the review of any proposals to stock more non-native fishes in the Upper Basin was over- hauled and greatly strengthened at the end of 1993, but was then withdrawn mostly at the urging of the Colorado Division of Wildlife (CDOW). The CDOW is now proposing to eradicate non-native fishes in ponds with connections to habitat occupied by the listed fishes, but then to promote the re-intro- duction of three non-native sportfishes (bluegill, black crappie, and largemouth bass) into some of those same ponds. The CDOW believes that the historic escape- ment and survival of these three non-native fishes has been quite limited and does not pose a threat to the