Roger W. Rottmann

Limnological and Ecological Effects of Grass Carp in Ponds

The feeding activity of grass carp (Ctenopharyngodon idella) significantly reduced the final biomass of submerged plants in Missouri ponds. Water quality was improved; total alkalinity and pH were sustained at levels more suitable for productivity. Nocturnal oxygen depletion was less severe. and noxious phytoplankton blooms did not develop in ponds stocked with grass carp. Grass carp had no significant effect on abundance of glass shrimp (Palaemonetes kadiakensis); bluegills (Lepomis macrochirus) had a much greater negative effect. In six of eight ponds with grass carp the densities of...