Alfred C. Fox

Macrophyte Control by Grass Carp in Catfish Ponds

Macrophyte standing crop (primarily Eleocharis and Utricularia) was reduced nearly 90% in two catfish ponds after introduction of grass carp (Ctenopharyngodon idella). Abundant vegetation remained in 1-m2 exclosures placed in the ponds as controls. The stocking ratio of grass carp (live weight) to macrophyte standing crop (dry weight) that resulted in vegetation control within 1 year was 0.15 in the pond is which the fish were fed pelleted food and 0.06 in the pond in which the flsh were not fed. Scattering of feed over the entire pond rather than conflning it to a few locations may have...

Food Habits, Growth, and Catchability of Grass Carp in the Absence of Aquatic Vegetation

Grass carp (Clenopharyngodon idel/a) were stocked into a 3.6-ha Georgia pond devoid of vegetation to simulate conditions that might occurr in a pond where grass carp have eliminated the macrophytes. The flSh were readily captured by hook-and-line fishing. The stomachs of 417 grass carp contained primarily terrestrial macrophytes; no fish or fish eggs were found. Many of the grass carp examined weighed less than when they were stocked.