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decreased for two days after stocking, but still indicated that <br />downstream, nighttime movements were the norm. No razorback <br />sucker were taken in hoop nets during daylight 15 September <br />before termination of the study by flooding. <br />Analysis of catfish stomach contents verified 1984 results <br />indicating significant predation on stocked razorback sucker <br />fingerlings. Razorback sucker occurred in 4b% and 79% of cYiannel <br />and flathead catfish stomachs, respectively (Table 8). While <br />razorback sucker occurrence was higher in flathead catfish <br />stomachs, channel catfish consumed stocked fish at higher rate <br />(Table 9). Size of stocked fingerling consumed was strongly <br />correlated (r2=0.76} with size of the predator; channel catfish <br />(216 f 69 mm SL) consumed smaller razorback sucker than flathead <br />catfish (287 f 108 mm SL). Predation rate coupled with <br />population estimates for both catfish species indicates that <br />potential predation in this reach of the Gila River is <br />558 razorback sucker fingerling consumed per hectare per 24 hour <br />period. Estimated predation on stocked razorback sucker <br />fingerlings for the Gila River from the study area downstream to <br />Safford (ca. 35 km) is SO,000 in a two day period. <br />Discussion <br />Prospects for recovery of the razorback sucker in the lower <br />basin depend l argely upon how the remaining. five years of the <br />reintroduction and monitoring MUU between USFWS and AGFD is <br />carried out. Data indicate that the presence of introduced <br />predators is a primary factor affecting success of this ongoing <br />-7- <br />