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i moderate depths (1.2 to 3 m) had on average larger condition factors than fish that utilized either shallow (<1.2 m) or deep (>3.0 m) habitats. The reason for this affect of condition factor upon depth selection is unclear, but there are at least three possibilities. First, fish with large condition factors may be more "plump" than their kin because they are more efficient foragers. If this is the case, then it follows that Green River habitats of moderate depth should be more productive than either deep or shallow zones. It is not known if this true. However, this hypothesis is testable since the diet of razorback suckers is known to consist of benthio insects, such as Ephemeroptera and Chironomidae, algae, detritus, and other items such as Cladocerans in reservoirs (Banks 1964, Jonez and Sumner1954, and Vanicek 1967), and the availability of these items could easily be compared at these water depths. A second explanation is that habitats of moderate depth may require fish to expend either greater or lesser quantities of energy to maintain position than either shallow or deep habitats. This does not seem to be a correct statement since there was no correlation between condition factor and current velocity. In addition, the condition factors of fish observed to utilize backwaters were not statistically different from the condition factors offish found in eddy pools, near shore, or in the main channel. A third explanation is that habitats of moderate depth are more competitive environments for razorback sucker than either shallow or deep habitats, and high condition factor fish have an advantage over low condition factor fish when involved in competitive interactions. This azgument does have some merit in that Abbot et al. (1985) found that a weight advantage of only 5% was enough to ensure dominant status during paired intra- specific competition in steelhead trout, and that the razorback suckers used in this project had condition factors that were positively correlated with length. It then follows that a larger fish involved in inter-specific competition for a food item, current refuge, space, ' etc., would fair better than a smaller or thinner fish. A Potential Explanation for the Large Initial Dispersal of Stocked Fish Often fisheries biologists attribute the high initial dispersal rates of stocked fish to transport and handling stresses (Bonga 1997, Salonius and Iwama 1993, Waring et al. 1996). These stresses have been shown to cause fish to respond by secreting higher the resting levels of the hormone cortisol (Barton and Zitzow 1995, Clearwater and Parkhurst 1997, Parkhurst and Dedual 1994, Wallin and Van den Avyle), which can have major physiological consequences. Higher than normal circulating cortisol levels cause fat stores to be mobilized (Waring et al. 1996), circulating lymphocyte levels to decrease (Barton and Zitzow 1995, and Salonius and Iwama 1993), osmoregulatory imbalances (Bonga 1997, Barton and Zitzow 1995), and even lead to follicular atresia (Clearwater and Parkhurst 1997). Chronic stresses such as overcrowding or intra- ' specific competition for resources can result in submissive behavior and the loss of access 19