THE TUNA INDUSTRY 91 



expansion valves to the steel coils which line the wells. The suction side 

 of each set of well coils is similarly connected to a return manifold. Each 

 well also has a separate system for circulating brine or sea water. The 

 hquid is pumped into the top of the well by the coaming via a gooseneck 

 and passes out at the bottom through a bait screen. The separate brine 

 systems for the various wells are connected to common headers through 

 valves. Thus by suitable switching, brine may be circulated or trans- 

 ferred from one well to another as required, or sea water may be pumped 

 from a sea-chest through the well or bait boxes for storing live bait. 

 This arrangement is very flexible to meet the many different situations 

 which arise at sea. 



A few boats use a brine spray system in which brine is pumped over 

 a head exchanger using ammonia or "Freon," projected as a spray over 

 the fish, and then drawn off for recirculation. There is a good deal of 

 argument as to the relative merits of the two systems, neither being 

 strikingly superior, at least as presently used. 



For bait boat fishing, anchoveta (Centergraulis mysticetus) or some 

 similar small anchovies or herrings are caught using a small mesh seine 

 net and brailed alive into the live bait tanks and available wells. When 

 tuna are sighted, the live bait or ''chum" is thrown into the water causing 

 the fish to develop a "biting frenzy." The crew fish from racks let down 

 over the side and stern of the boat near the waterline using bamboo poles, 

 some 8 feet in length. The biting fish take the hook and are pulled inboard 

 behind the crew. When large fish are encountered, 2 and even 3 lines are 

 joined to one leader, and the 2 or 3 fishermen work in unison to haul 

 them in — a spectacular and highly skilled operation. 



The procedure described above has now given way in large measure 

 to purse seining. The bait boats are mostly converted by removing the 

 bait tanks, racks, and part of the amidships deck on the port side, so as 

 to clear the afterdeck for the installation of the net, turntable, winches, 

 booms, controls, etc. The storage wells and refrigeration equipment are 

 generally unchanged. An excellent description of modern tuna seining 

 gear and its operation has been given by McNeeley^^ 



Albacore is largely trolled by jig boats, mostly operated in the short 

 summer season only. These boats have a 2- to 20-ton capacity, and, being 

 out for short trips only, carry little or no refrigeration. Some albacore is 

 also landed by bait boats and seiners. 



Storage and Transport. The Atlantic bluefin seining is a day operation 

 and no ice is used. The freezing process used by the Pacific fleet is sub- 

 ject to so many operating variants that it is far from standard, but the 

 following is a typical procedure. 



Usually two wells are filled with sea water chilled to 30 to 32°F before 



