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. -10- rate of about lOmm and 8mrn per monr,h, respectively; or about one-r.a1f of the year-lcr.g rate for the fi~h planted in 1963. The closely grouped lo<.gth .distribution of yaung-of-the-year stoc~ed bass (Figure 3) indicated th2.t a:'J natural reproduction probably occurred late in GUmrr:er. For :.:.he Lake Po\,;ell spawned bass to have been the same size as the stocked bass on the dates taken} natural spawning would have had to occur in February or ~arch when water temperatures were below thresholds. Water tem~erature records show that surface readings did not approach bass spawning thresholds u~til at least late April. The length-weight curve of bass sampled in 1964 is given in FiG~re 4. Comparisons with other waters confirm the very favoraqle groi.~h for the early years in Lake Powell. At age one, the 1963 plants show an average length and weight equal to bass from Conchas Reservoir and Lake p~ad} and compare favorably with bass growth during the early years in Iiorris Reservoir. There was a tendency for anglers to report bass in the upper portion of the reservoir (above Rock Creek) as being generally l.:t.rger th:.lll tllo::;c inhabiting the lower reaches. Data from very s~all samples sho"; ttat bass taken near Hall's Crossir:g after November, 1961~ averaged 50rm:l larger than those in the vicinity of K3.hweap and Las'"C Chance. Age-length results from 85 bass scales read during this period (Table 4) show that young-of-the- year fish in the Hahweap to Last Char;.ce area had the fastest gro....-th when compared to fish taken up-reservoir, but that durinG the subsc\l\.:ent year of lire, fish in the uppcr rescrvoir cClucht Clnd ;,urpCl:;scd those below. Condition factors ("K") were calculated for ::'03 large:nouth bass. Table 5 sho~s a bass popul~tion in good condition. The young-of-the-year fish show a decrease in "K" between the s:.Jallest ler.gths sampled ctnd about 125~m total length. Condition factors for these fish averaGed about 2.7