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5 An unusual flash flood occurred during the weekend of August 10, 1992, moving much litter, debris, and sediment into Yuma Cove. Upon first discovery of the event, researchers were concerned that the juvenile suckers had perished, but just the opposite happened. The flood waters had positive physical and chemical effects. The backwater temperatures cooled, oxygen levels increased, turbidity greatly increased and reduced algae growth, and most significant, the material flattened the weed beds in the center of the cove which helped the netting effort. Sampling effort three days after the storm event resulted in the capture of 32 juvenile fish, and a total of 115 young suckers were captured during August following the flood event (See Table 1). Pondweed did not reestablish until October, and then it only developed along the shoreline, not in the center of the pond. HARVEST: A decision was made at the NFWG meeting in October to remove the remaining juvenile razorback suckers from Yuma Cove. Fourteen members of the NFWG used a combination of trammel netting and electrofishing to remove 109 suckers during the week of November 23rd. The average size of these fish was 354 mm and all 109 were PIT tagged and stocked into Lake Mohave. Of remarkable significance was the finding of 6 _ ripe males among these juveniles. This is the earliest age ever recorded for razorback suckers reaching sexual maturity. These males were tuberculate and expressing milt. Following this effort, the organic respiratory fish toxicant rotenone was applied to the backwater. Five additional suckers were collected by this technique. Three were revived and released (included in the 109), and two fish perished and were transferred to ASU laboratory for genetic analyses. The total harvest of juveniles from Yuma Cove to 296. ASU examined the total production of Yuma Cove (Appendix D). The two most noteworthy observations are that genetic investigations showed at least ten of the 29 females originally selected produced young in Yuma Cove. Second, the overall growth was phenomenal, but the level of production is extremely low. If the NFWG is truly going to attain the goal of replacing the existing 60,000 adults, the effort needs to be greatly expanded.