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19 <br />Down-reservoir transport of larvae would be a result of deep <br />currents. Portz (1973), Priscu (1978), Baker and Paulson (1980), and <br />Paulson et al. (1980) all discussed warm weather currents induced by <br />thermal differences between inflow from Hoover Dam and the body of Lake <br />Mohave, prevailing winds, and morphometric characteristics of the lake. <br />Potentially strong currents also must develop because of flow-through at <br />other times of year. Using conservative parameter estimates for cross- <br />sectional area (CSA) of 19,500 m2, and discharge (Q) through the lake of <br />500 m3/s, we estimate a current velocity of about 2.6 cm/s. Expanding <br />this relationship to include CSA's of 5,000 to 40,000 m2 and Q's of 100 <br />to 1000 M3 /S (Fig. 8) we find that current velocities of 1.0 to 25 cm/s <br />are not unreasonable. In fact, if deep currents are constrained, <br />perhaps by canyon walls of the original Colorado River channel or by <br />weak thermal stratification in late winter-early spring, CSA may be even <br />smaller and potential current velocities even higher than these figures. <br />Larvae continuing to move or be moved down-reservoir may be depleted by <br />predation, with the remainder ultimately discharged through Davis Dam. <br />A few survivors may explain the scarce individuals collected in more <br />downstream habitats. <br />Down-reservoir currents also may combine with prevailing winter <br />winds and local hydraulic conditions to "stockpile" sucker larvae in the <br />Hammerhead Cove area. Hammerhead Cove is near the point at which Lake <br />Mohave widens into Cottonwood Basin (Fig. 1) and just upstream from a <br />substantial deepening of the lake (Paulson et al. 1980). Local currents <br />could exist which in effect transport larvae toward and into Hammerhead <br />Cove where they are temporarily entrained.