HARVEST AND GEAR TECHNOLOGY

Scientists:
Ed Robinson
Doug Minchew

Support Personnel:
Susan Bailey, Research Associate I

Harvesting and grading methods utilized in the channel catfish industry have remained relatively unchanged for years.   The purpose of the harvest and gear technology research program is to improve harvest and grading efficiencies by developing innovative harvesting and grading equipment. Conventional seines have been fitted with features adopted from marine harvest equipment, including neutrally buoyant mud rollers, brummel hooks, and enlarged zippered socks and tunnels.  A number of materials (twisted nylon, braided polyethylene), webbing orientations (square, diamond), and knotted and knotless webbing have been tested for durability, catch rate, and grading efficiency.  These advances in harvest technology will help catfish producers decrease money lost due to penalties levied by processors for fish that are larger or smaller than the acceptable size range. Additionally, the producers will be able to improve profits by increasing catch rates, reducing seining and holding stress, and decreasing labor costs associated with the seining.

Efforts are underway to evaluate the potential of using electricity to improve the efficiency of a conventional seine in harvesting catfish from ponds. Based on extensive vat studies (electrodes only) and limited pond studies (electrodes attached to a seine), it has been determined that a low to high varying frequency waveform electrode system can be used to improve the harvest efficiency of a conventional seine.  Harvest trials were conducted to compare the catch efficiencies of a conventional seine and an electrically enhanced seine in removing channel catfish from ponds.  The average total harvest was 22% higher using the electrically enhanced seine.  The electrically enhanced seine is currently being redesigned.  New technologies will be developed to keep more of the seine energized at all times and to make the electrical components more compact, robust, safe and user-friendly.   This technology has the potential to significantly improve the harvest efficiencies of conventional seines thereby reducing seining costs and preventing the buildup of over-sized fish in production ponds.