Laserfiche WebLink
22 <br />i <br />larvae hatch in Lake Mohave, nor the efficiency of yolk utilization, <br />nor their rate of growth at ambient lake temperatures. However, <br />larvae captured from Take Mohave proper all have had reduced yolk-sacs <br />or are of a size when yolk should have been recently absorbed, and <br />have had predominately empty stcmachs (t,,h & Langhorst 1988). Also, <br />larvae captured in Take Mohave were estimated to be not vouch older <br />than 19 d (Iorst & Marsh 1986), thus it appears that essentially <br />all wild-caught larvae have been in the transition from endogenous to <br />exogenous foods, and therefore, in the critical period. The amount of <br />time larvae have to encounter suitable food at Lake Mohave <br />temperatures is not precisely ]mown. All my experimental mortalities <br />were greatest between 20 and 30 d after hatching at 180C. At ambient <br />reservoir temperatures (9 to 150C) this critical period would <br />presumably be extended a few days, at least. Nonetheless, the <br />consistent absence from collections of razorback sucker larvae of <br />sizes that have obviously succeeded in passing through the critical <br />period, may in fact document that food-related mortality contributes <br />to year-class failure in the. Iake Mohave population. <br />i. <br />i <br />j