SHARK BARRAGE

Evening Star, Issue 22070, 2 July 1935, Page 5

SHARK BARRAGE

EXPERIMENTS WITH GAS Experiments with carbon-monoxide gas as a deterrent to sharks have been carried out at the Manly Aquarium, and proved more successful than on previous occasions, says the Sydney ‘ Sun.’ A small pipe line was lowered into the water, and from this the car-bon-monoxide escaped through small holes drilled and fitted with valves. The gas escaped in a curtain of bubbles to the surface. So that the four grey nurse sharks would face the tube, long sticks were used to prod them, but they only went about four feet from the bubble barrage, and quickly turned away. This was tried several times with the same result. The inventor of the apparatus, Mr F. Bland, of North Sydney, was very pleased with the demonstration which was witnessed by a number of people, including some expert fishermen. The demonstration was carried out in about four feet of water, which was calm. Mr Bland, however, is quite confident that this method of fighting the shark menace could be effectively used in the surf, and he has plans prepared showing what could be done in deeper water or the surf. He pointed out that the test pressure was only 5 lb. which could be increased to 100 or 2001 b if necessary. At a recent experiment in the aquarium, fish bait was placed close to the pipe line, and though the sharks were very hungry thev would not take the bait, owing to the smell of the fumes from the apparatus. • One point that impressed onlookers was the ease with which the huge man-eaters swum about in a few feet of water, showing definitely that there is a risk in swimming in unprotected places. ____________