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Abnormalities observed in all treatments in this study were usually so severe (pronounced <br />spinal deformity, ballooning of the abdominal cavity) that these fish would not survive in <br />the wild. <br />Developmental Rates and Growth <br />Rates of development of Colorado squawfish embryos and larvae varied directly with <br />water temperature. Reasons for the markedly longer hatching interval at constant than at <br />fluctuating regimes at 18 and 22°C are unknown. Fluctuating temperatures at 18 and 22°C <br />may have also shortened the time to swim bladder inflation and exogenous feeding. <br />Despite statistically significant differences in lengths of larvae in some treatments, it is <br />improbable that the small differences observed for either newly hatched (difference among <br />mean lengths in treatments < 15%) or 7 d post-hatch larvae (difference < 5%) are of <br />ecological significance. Different endogenous feeding rates between treatments may be the <br />reason for differences in fish lengths. <br />Times to developmental events and length measurements were recorded irregularly in the <br />30°C treatment due to low hatching success and poor condition of larvae and may be less <br />accurate than those reported for the other treatments. Time of first hatch and swim bladder <br />inflation may not represent the norm due to rare events (e.g., very early hatch or air bladder <br />inflation in a single fish). The times to first feeding that we report are more reliable <br />because most fish in a treatment chamber began to feed almost simultaneously, thus <br />reducing the potential influence of rare events. <br />Management Implications <br />12 <br />