Pumps, K-ping and Hydraulics 



The pumps and piping system for bait water and brine circulation 

 are highly efficient, but refinements providing greater versatility 

 are being developed. The use of hydraulic pumps may be an innovation 

 ■which could eliminate or greatly rsduce the complicated electrical 

 systems. Efforts are being made to develop plastic piping which 

 would not be subject to corrosion, electrolysis or the attachment of 

 marine growths. 



Electronic j>ids to Fishing and Navigation 



New types of navigational equipment, such as loran (long-range 

 navigation), radar (radio detecting and ranging), and the widespread 

 use of supersonic depth recorders for locating schools of fish have 

 materially increased fisherj'- production in general since World War II, 

 The continuous improvement of these devices and the development of 

 new devices such as echo-ranging equipment, underwater listening 

 equipment and electrical fishing apparatus will undoubtedly bring 

 about greater efficiencies in fishing operations in the future with 

 an attendant increase in fishery production. But a great amount of 

 basic research is required before working sets of this advanced type 

 of equipment can be made available to commercial fishermen. The 

 extent to which these improvements and developments will increase 

 fishery production is difficult to evaluate now, but it may be 

 expected to be appreciable. A radical change in fishing methods such 

 as the development of an electric fishing ship might revolutionize 

 entirely commercial fishing operations as they are now carried out 

 in certain fisheries. 



Fishing vessels equipped with radar can operate with greater 

 safety at night and during periods of poor visability. Tuna schools 

 feeding near the surface are frequently accompanied by d ense flocks 

 of birds which can often be located more readily by radar than by the 

 human eye, Loran has eliminated laborious computations formerly re- 

 quired to determine the vessels' position and has made possible the 

 determination of position at any time during the day or night, Loran 

 can materially reduce the man hours spent at sea by enabling the 

 fisherman to place his vessel on a precise spot of a particular fishing 

 bank in a minimum of time. Commercial fishermen in constantly growing 

 numbers find the supersonic depth recorder very useful for locating 

 schools of fish. Unfortunately, depth recorders have fundamental 



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