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20 <br />Bay area when comparing similar sample hours. March sampling was <br />conducted specifically for bonytail chubs, and some nets were set in <br />different areas. Re-calculated catch rates for March 1982 are presented <br />in Table 1. These re-calculated rates exclude day sets and non-spawning <br />area sets that were not part of routine monthly sampling. These rates <br />are similar to those for the Arizona Bay area during the same month. <br />An increase in catch rates of other species was evident in April in <br />the Six Mile Coves while those of the razorback began to decline (Fig. <br />4). By May, razorbacks had fallen to third in abundance as spawning was <br />nearly complete. Seasonal trends were similar in both areas with <br />razorback suckers dominating the catch from January-April. Other species <br />became more abundant in these areas during April and May. <br />Razorback suckers were present in the spawning areas in the Six <br />Mile Coves area and elsewhere by November 1982 (Fig. 5). While catch <br />rates were high due to low net hours, razorbacks were abundant in these <br />areas. Razorback suckers dominated the catch in January and February <br />during 1983, but by March, nearly the entire Six Mile Coves area had <br />been vacated by razorbacks. Spawning activity and numbers of razorbacks <br />remained high in cove areas to the north and south of the Six Mile Coves <br />area and in Arizona Bay. Water temperatures in all spawning areas were <br />similar in March. <br />Heavy storms during the week prior to the sampling in March <br />appeared to be the reason for the sudden disappearance of razorback <br />suckers from the Six Mile Coves area. Large amounts of suspended <br />sediment, detrital and organic material were present in the water and <br />turbidity was high. Gravel spawning areas here were silted over. The <br />shorelines in the cove areas of the Cottonwood Basin and the Arizona Bay