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I I 10 .J l-:) i''' ,;>. ~, C.il ?..:' , : r~ Due to the significant effect of day on growth, absolute growth rates (AGR) were calculated for each exposure period and analyzed using the same ANOV A procedures described above. Absolute growth rates based on body weight (AGR-W, g/d) and total length (AGR-L, mm1d) were calculated for each period according to Ricker (1979) as follows: AGR-W (g/d) = WI-Wi OJ -0; AGR-L = 1i -Li OJ-O; where Wj = body weight at end of period, Wi = body weight at beginning of period, LJ = total length at end of period, L; = total length at beginning of period, OJ =day of study at end of period, and Oi = day of study at beginning of period, Absolute growth rates based on body weight varied significantly among exposure periods (F=5.16, P<O.OI), but not among treatments (F=0.16, P=0.97). As was observed for weight, AGR- W differed between sexes (F=6,59, P=0,02) and there was a significant interaction between s~x and day (F=2.70, P=O.Ol). Because there was no effect of treatment, AGR-W were pooled across treatments (Table 7). Mean AGR- W for fish in each treatment are given in Appendix F. Adults of both sexes exhibited negative growth during the first 30 days of the study (mean AGR-W, -3.31 and -1.12 g/d) and during the depuration period (mean AGR-W, -2.57 to -0,30 g/d; Table 7). The largest mean AGR-W for both sexes occurred from days 58 to 90 (1.18 and 2.67 g/d) and following this peak:, the AGR-W in females decreased significantly to day 184. For three of eight periods, average daily weight loss in females was at least 1.5 g/d more than in males and these differences were significant or close to being significant. The ability to detect statistical differences in AGR- W at the 5% level of probability was probably hampered by the large variability in the data; differences between minimum and maximum AGR-W ranged from 10.82 to 43.79 g/d for females and 3.40 to 5,77 g/d for males, " JJ