HARVEST AND GEAR
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.