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21 <br />produced fish 14.9±0.4 nun TL (N--4) and those at 500 and 1,000 nauplii <br />L`1 had larvae 25.0±0.6 and 23.7±0.6 ram TL (W27 each). <br />It has been shown elsewhere that larval fish will reabsorb tissue <br />and lose weight, and perhaps length, when starved (Ivlev 1961). <br />Larval razorback suckers that were not fed were slightly smaller at <br />death than when stocked. Those which died from insufficient food were <br />approximately the same size at death as when stocked, indicating a <br />small amount of growth before starvation. Fish that were starved to <br />death measured 9.6±0.1 mm, TL (N=28), those which died from delayed <br />feeding were 9.3±0.2 TL (135), and those that died from insufficient <br />food measured 10.1±0.2 mm. TL (W25). <br />Growth during the stages when larvae depend on endogenous food <br />and switch to exogenous food is related to temperature and its effect <br />on efficiency of yolk utilization (Laurence 1973, Houde 1974). It may <br />therefore be difficult to predict size at which fish larvae from <br />different thermal environm ents will die due to insufficient food. <br />Lake Mohave, for example, is colder (9 to 150C) during the period of <br />incubation and hatching for razorback sucker (Marsh 1985) than was my <br />experimental system (180C). I predict larvae in Lake Mohave to be <br />larger at hatching, with a reduced yolk-sac, yet able to survive with <br />inadequate food for a longer period (Houde 1974). However, Marsh <br />(1985) found that although razorback sucker larvae hatched almost twoo- <br />UArds as slowly at 1500 as at 2000 (132 vs. 204 h) TL at swim-up was <br />not significantly different at the two temperatures (8.5 vs. 8.4 mm). <br />No information is available on the size at which razorback sucker