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agonistic behavior or competition for food, space or other limited resources--might occur <br />among adults or perhaps between adult Colorado squawfish and other fish species. It <br />might therefore be hypothesized that the energy cost involved in returning to former <br />feeding/wintering areas is ultimately less than that which the fish would experience if it <br />attempted to reside in a new feeding/wintering area subsequent to spawning. As Olson <br />et al. (1978) suggested for walleye (Stizostedion vitreum), Colorado squaw-fish might <br />seek suitable adult habitats as they mature and establish residency in areas where <br />habitat not occupied by other squawfish is available. A knowledge of the location and <br />characteristics of the particular feeding/wintering area that it selects is then retained by <br />the fish. Such memory thus allows the fish to return to this area after spawning <br />elsewhere. If this hypothesis is correct, the loss of a river reach that includes <br />feeding/winter habitat for adult Colorado squawfish, the 15-mile reach for example, <br />could result in a real reduction in the adult squawfish population or--of equal or greater <br />importance--in the potential size of the population that may be achieved as a result of <br />recovery efforts. <br />Our flow-habitat management objective for July, August and September is to <br />maintain a near-maximum amount (95% or more) of the aggregate run, pool and riffle <br />habitat in the 15-mile reach. In so doing, we believe each of these three important <br />habitat types will occur in sufficient quantity to assure that their availability will not <br />prevent the achievement of recovery goals for Colorado squawfish. <br />9