EARLY REARING OF CHANNEL CATFISH FRY IN FLOATING RACEWAYS AND SUBSEQUENT SURVIVAL IN PONDS

We tested an airlift-operated floating raceway in which fry of channel catfish (Ictalurus punctatus) were raised from swim-up stage to 5 cm total length (TL) before stocking into rearing ponds. Survival of fry raised in this manner was compared with that of swim-up fry stocked di rectly into rearing ponds. Swim-up fry stocked into two 1.87-m(3) floa ting raceways at a density of 21,390 fry/m(3) (40,000 fry/raceway) gre w to 5 cm TL within 27 d and had an average survival of 90.3%. When th ese fry were subsequently stocked into two 0.2-ha ponds for further re aring, 95.2% survived to 12.5-cm fingerling size. Overall, survival fr om swim-up stage averaged 84.1%. Survival in ponds stocked with swim-u p fry averaged 84.1%. Unaccounted fish losses during the pond-rearing phase were lower in ponds stocked with raceway-reared fry than in pond s stocked with swim-up fry (4.1% versus 14.7%, respectively). Although overall survival of raceway-reared and pond-reared groups was similar , the Boating raceway system offered advantages over traditional direc t pond stocking because early poststocking survival was easy to determ ine and channel catfish fry were easier to feed, observe, and treat fo r disease.