. Commercial fisheries review. Fisheries; Fish trade. 28 COMMERCIAL FISHERIES REVIEW Vol. 19, No. 12 North Atlantic Herring Research DRIVING HERRING SCHOOLS WITH COMPRESSED-AIR CURTAIN: Field ex- periments on the driving of herring schools were conducted by Boothbay Harbor, Me., staff of the Bureau of Commercial Fisheries during the last week in August and the first nine days of September 1957, A "wall" of compressed air discharged on the sea bottom was tried in these experiments as a means of influencing the movements of herring schools. After several weeks of building and testing t
. Commercial fisheries review. Fisheries; Fish trade. 28 COMMERCIAL FISHERIES REVIEW Vol. 19, No. 12 North Atlantic Herring Research DRIVING HERRING SCHOOLS WITH COMPRESSED-AIR CURTAIN: Field ex- periments on the driving of herring schools were conducted by Boothbay Harbor, Me., staff of the Bureau of Commercial Fisheries during the last week in August and the first nine days of September 1957, A "wall" of compressed air discharged on the sea bottom was tried in these experiments as a means of influencing the movements of herring schools. After several weeks of building and testing this gear at the Boothbay Harbor Research Station, it was taken aboard the 35-foot motorboat Clu- pea to Tenants Harbor for the field trials. In this area, working in cooperation with a sardine fisherman from St. George, Me., tests of the gear were made on actual schools of herring. The fisherman performed the essential task of spotting the schools from the air in his piper cub airplane and of directing the setting of the gear. All observations of the effects of the air discharge were also made by airplane. The trials were made at Pleasant Island near Ten- ants Harbor. The gear used consists principally of an industrial-type air compressor, a 700-foot length of flexible polyethylene pipe with an in- side diameter of inches, and a power- driven hose reel with air fittings to allow set- ting out and hauling in the plastic pipe while pumping air. The compressor was capable of delivering 60 cubic feet of air a minute at a maximuna pressure of 75 pounds a square inch. This compressor was connected through the hose reel to the plastic pipe--500 feet of the pipe was driUed at one-foot intervals with a JL -inch diameter drill and weighted with a wrapping of lead wire to make it sink.^An additional 200 feet of the pipe, undrilled and unweighted, was connected between the drilled piece and the hose-reel outlet. The gear thus assembled was capable of discharging air bubbles along the
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