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7 <br />Adults remained common in Arizona Bay through April, although only a <br />few hundred at most were present after mid-February. Spawning had <br />ceased by 1 May (Table 1) and all but a few adults had abandoned the <br />area, presumably for deeper water. Adults in Hammerhead Cove were <br />depleted by sampling to obtain fish for propagation on 27-30 January, <br />and the area was not again repopulated to former densities. Although a <br />few razorback were caught periodically through February and March and <br />several were observed in early April, no spawning was detected during <br />twice-weekly site visits after January. <br />Up to 15 individuals of the stock of razorback sucker transferred to <br />the backwater were observed along shallow shorelines on 6 of 35 site <br />visits there between January and April. Spawning acts were not seen, <br />but must have occurred since reproduction was successful (see below). <br />LARVAL DISTRIBUTION, ABUNDANCE, AND GROWTH <br />Razorback sucker larvae were first captured on 9 February in Hammer- <br />head Cove, 3 weeks after initial spawning observation at that site and a <br />month after onset of spawning in Arizona Bay (Table 1). Sampling was <br />generally at night when small fishes could be attracted to a spotlight <br />and collected by dip net (Bozek et al. 1984, Langhorst et al. 1985). <br />Additional collections were in daylight. Larvae became abundant in <br />Hammerhead Cove within the next few days, although none was collected at <br />other locations until 17 February. Larvae could thereafter be found <br />sporadically in Cottonwood Cove (Nevada) and Arizona Bay (Fig. 3). <br />Despite extensive reproductive activity observed in Arizona Bay, few <br />larvae were captured there. In contrast, larvae remained common in