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Timing of Developmental Events <br />At a given temperature level, times to first hatch, 50% hatch, and 100% hatch were <br />generally similar for fluctuating and constant regimes (Table 1). For example, time to <br />initiation of hatching differed by 41 h between 18 and 26°C treatments (regimes combined). <br />However, times for each hatching event interval between the 18 and 26°C treatments <br />(regimes combined) were nearly equal (41-42.5 h), suggesting that once hatching began at <br />any temperature, times to midpoint and end of hatching were about equal across all <br />temperatures. In general, swim bladder inflation and first feeding occurred sooner at higher <br />temperatures and also at fluctuating temperatures. <br />Lengths of Larvae <br />Length at hatch (Table 1) differed significantly for temperature level but not for regime, <br />or interaction (Table 2). Lengths were significantly different in 18 and 26°C treatments, but <br />not in the 22 and 26°C or 18 and 22°C treatments. Lengths at d 7 differed significantly for <br />regime and interaction but not for temperature level. Most interaction significance was due <br />to faster growth in the fluctuating regime at 22°C. <br />Discussion <br />Hatch and Survival <br />Results presented here generally corroborate those of previous laboratory studies. We <br />also found hatch and larval survival were generally higher over a wider range of <br />temperature conditions than previously reported. This may reflect the low density of <br />embryos and the rapid exchange of water in our incubation chambers which minimized <br />9 <br />