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in late May or early June as the water temperature approaches <br />700F. Male squawfish develop heavy tuberculation over most <br />of their body as they ripen and exhibit a golden green sheen <br />compared to their normal olivacious green coloration. As the <br />egg masses approach maturation in female Colorado squawfish, <br />their abdomen softens and deepens and the genital papillae <br />becomes reddened and flowery. Although some females ripen <br />slightly ahead of others, we have found that all female squaw- <br />fish must be spawned within a one to two week period once they <br />have ripened or good eggs cannot be obtained. Eggs force- <br />ovulated prior to this time or taken after the spawning peak <br />have a very low viability if they are good at all. This requires <br />close monitoring of the female brood fish to ensure procurement <br />of viable sexual products. <br />Female Colorado squawfish are injected with carp pituitary <br />(CP) to stimulate ovulation of maturated eggs. Hamman (1981) <br />determined that two mg per pound of body weight injected in- <br />tra peritoneally was the appropriate hormone, dosage and method <br />of injection. Male Colorado squawfish normally stay ripe and <br />fluid but receive injections of HCG at 150 IU per pound of body <br />weight if fluidity decreases. <br />Colorado squawfish eggs are handstripped into pans utilizing <br />the wet method as described for razorback suckers, milt from two <br />or more males added and the eggs gently stirred with a feather to <br />help ensure adequate mixing of the sexual products. Like razorback <br />sucker eggs, Colorado squawfish eggs are extremely adhesive so the <br />fertilized eggs are "clayed" to break down the adhesiveness and <br />prevent clumping of the eggs. The eggs are then water hardened, <br />enumerated and layed down for incubation as described for razorback <br />suckers. Unlike razorback sucker eggs however, Colorado squawfish <br />eggs can be hatched in Heath incubators or jars. In 1983 egg <br />viability averaged 590/10 in Heaths and 66,0' in jars. However, viability <br />percentages were more closely related to egg quality than to hatching