ARS | Publication request: Experimental evaluation of the effect of winter feeding on channel catfish growout pond plankton

Submitted to: Proceeding of World Aquaculture Society
Publication Type: Abstract Only
Publication Acceptance Date: December 10, 2008
Publication Date: N/A

Technical Abstract: Ten, 0.25 acre ponds at the UAPB Aquaculture Station were sampled weekly from Dec. 7-Feb. 22 (n=90) for phytoplankton and zooplankton. Five of the ponds were randomly assigned to each of two treatments: no feeding and feeding based on recommended rates. Channel catfish sizes and numbers approximated a typical winter carryover scenario. Algal biomass was low and not significantly different. Average combined algal natural units were significantly different (P=0.02) and more than twice as high in fed ponds. Composition between treatments was not significantly different. Diatoms were the most abundant group. Zooplankton did not differ. Off-flavor cyanobacteria were two species of Anabaena and Pseudanabaena sp. These off-flavor algae were found on 7 of the 9 sampling dates in fed ponds and 9 of 9 in unfed ponds and occurrence was significantly higher in unfed ponds (P=0.08) by 70%. Thus, algae in fed ponds were smaller and off-flavor algae less common than in unfed ponds. Winter feeding of channel catfish may benefit algal composition.