Food habits and growth of silver and bighead carp in cages and ponds.
Food habits and growth were studied in silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) [Aristichthys nobilis] kept in fertilized ponds, or given artificial feed, or both. From gut contents, silver carp ate mainly phytoplankton; bighead carp ate zooplankton and detritus as well as phytoplankton. Silver carp filtered particles of 8 to 100 mu m; bighead carp filtered 17 to 3000 mu m. Bighead but not silver carp took artificial feed readily, as floating pellets, and those given it grew larger than those not given it. Growth was less for fish cages than in ponds, but in cages the silver carp grew more than the bighead carp. In some of the trials, the carp were grown with channel catfish [Ictalurus?]. Paper gives the species of plankton. Gut of silver carp was 3.5 to 7.3, mean 5 times the body length, and that of bighead carp was 2 to 4.5, mean 3.3 times body length.