SEA-LIONS THAT HUNTED U-BOATS.

Manawatu Herald, Volume XLI, Issue 1997, 1 July 1919, Page 4

SEA-LIONS THAT HUNTED U-BOATS.

In the summer of 101" (says the U’ustrated London News) the Adnn’•atty hit on a novel way of bunting ploy lame sea-lions (Otaria Gillespie) to track them down—the idea being that the sea-lion could he tam'ht to distinguish the noise of the submarine’s propeller and to follow it in the hope of getting foot. A buoy would he attached to the animal, and a trawler would fo on the buoy and drop a depth-charge when the sea-lion appeared to have found the submarine. The sea-hon would he released when a L-boat was suspected to be in the vicinity. To do this, two of the animals were purchased, and experiments first carried out in a lake. Noises Avere made under water on one side, j,nd the animal, on jumping in, heard the noise and swam towards it, hein" rewarded when he found it by a feed of fish; The noise was made by an electric buzzer under water. After a large amount of this practice, the animal was able to locate the sound each time. The animals were then taken down to Portsmouth, and practice was carried out with a real submarine. • The lirst experiments Avere carried out with the submarine in harbour with the buzzer. This was successful. The animal was throAvn overboard some distance off, SAvam to the submarine, and jumped on board for his accustomed feed of fish Avhicli he got. This was done several times to accustom him to the submarine. The next development Avas, Avhile still in harbour, to do a few revolutions Avith the propeller, sounding the buzzer at the same lime—this Avas to accustom the animal to the propeller. This also was successful, although the motors had to be stopped when he was near. A small, light, cigar-shaped float painted red Avas tied round the animal’s neck by a long piece of gut. In this manner the animal’s whereabouts was .ascertained as he (owed it along witlr him on top of the water. A portable cage Avas then made on the top of a steamboat, and the animals Avere taken outside. The same practice AA T as carried out with the buzzer and propellers, only at increased distances. The animals Avere fitted with small wire muzzles to prevent them going on a fishing expedition of their own. The practice Avas then carried out Avithoul; the buzzer, the submarine using her motors only. After about a week of this, the animal Avould discover the sound and jump on board. Great difficulty Avas experienced oaving to passing steamers, Avhicli the animal would hear and elm sc after. The final stage of practice was with the submarine diving. This was i rather taking a risk Avith the sub- ; marine’s propeller. The men in the i steamboat, as soon as the float was | observed near the periscope, would j signal the fact to the captain of the submarine, avlio was Avatehing through the periscope. The submarine Avould then stop motors and come to the surface. On several occasions the animal was on deck “barking” for food even before the captain could open the conning-lowcr hatch. Tins ended the experiment. The chief objections to this meth- ! od of hunting submarines were that ! the animal Avould sAvim after any : passing 'noise —such as another ship’s propellers —and that the ! boats Avere very unsatisfactory. It | was impossible to have a bigger j float, oA\ing to the strain on the J animal’s neck, and the small float i Avas very difficult to see at a distj a nee. The line, too, Avas continual- ( ly breaking; and for the same reason it was impossible to have a heavier and stronger line. Thin Avirc was tried, but that avus also unsatisfactory. Also, when the Avcather was ■ Avarm the animals did not behave •.<: .. li. i im two animals wore Californian ■a-lions, mm male and the other female. The male was found to be , much more intelligent and teachj able than the female. Perhaps the | fact that he had been a bit longer I in captivity, and was a bit older, j had something to do Avith it. We j “lost” the animals several times, but ' they always eventually returned . home on noises being made under 1 water.