Premium
Increasing Yields of Caged Channel Catfish in a Farm Pond by Sequential Harvests, with Notes on a Supplemental Harvest of Blue Tilapia
Author(s) -
Konikoff Mark,
Newton Scott H.,
Robison Walter R.
Publication year - 1988
Publication title -
north american journal of fisheries management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.587
H-Index - 72
eISSN - 1548-8675
pISSN - 0275-5947
DOI - 10.1577/1548-8675(1988)008<0091:iyoccc>2.3.co;2
Subject(s) - ictalurus , catfish , hectare , stocking , standing crop , fishery , zoology , tilapia , biology , cage , fish farming , fish <actinopterygii> , aquaculture , agronomy , biomass (ecology) , ecology , mathematics , agriculture , combinatorics
Our objective was to test a management scheme in which farm pond production of fishes could be increased by sequential harvesting. Periodic harvesting of caged channel catfish Ictalurus punctatus that were fed a formulated feed, caged blue tilapias Tilapia aurea , and wild fishes resulted in a gross yield of 3,207 kg in 6 months from a 1.6‐hectare farm pond. Previously, gross yields of caged channel catfish from this pond had been less than 1,360 kg/season. By stocking three sets of cages with three sizes of channel catfish fingerlings (averaging 54, 105, and 173 g) at the rate of 300 fish/0.9‐m 3 cage and harvesting each set as they reached a market size of 0.5 kg, the standing crop of caged catfish was kept below 1,000 kg/hectare and the gross pond yield of this species was nearly 2,000 kg/hectare. Periodic harvests and low standing crops avoided the need for progressively higher feeding rates that usually lead to progressively greater enrichment, phytoplankton abundance, and water quality degradation in traditional culture systems. The 6,000 channel catfish stocked in cages had over 97% survival and each fish averaged 463 g at harvest. After the first set of cages was harvested in July, three cages were stocked with small blue tilapias (300 fish/0.9‐m 3 cage) with an average weight of 17 g. These were not fed but after 99 d they averaged 64 g with over 98% survival. In addition, 435 kg of wild fishes (mostly channel catfish) were captured during the caged‐fish production period. By using a combination of cage culture, periodic harvesting, and removal of wild fishes, the annual gross yield of this farm pond was increased from less than 850 kg/hectare to over 2,000 kg/hectare. This level of harvest approaches that of well‐managed aquaculture ponds.