458 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



minutes of active attack, and for an encounter between tliem to last more than 

 15 to 20 minutes is unusual. 



On the other hand, in fishes reared under careful domestication and intelligent 

 selection of parents, the inherent desire and ability to fight are markedly 

 strengthened. Well-matched fishes may continue their attacks hour after hour 

 without intermission, with only brief excursions to the surface for air. There is 

 a partial respite from active effort while the fishes are in a sparring position, 

 but even then the fins are kept extended, the gill membranes remain expanded, the 

 body muscles are taut, and an alert attitude is constantly maintained. Some of 

 my own fishes have remained pugnacious after 6 hours of uninterrupted combat, 

 but fights do not ordinarily last moi-e than 3 hours. From reputable Siamese 

 informants has come the information that fish have been known to struggle for 

 a whole day and night. 



In Siam. as in the various countries into which the fish has been ijitroduced, 

 the usual procedure in arranging a fight is to select two males of approximately 

 the same size and bring them together in separate jars. If they spread their 

 fins, show their colors, and make head-on efforts to reach each other, they are 

 placed together in the same vessel. An ordinary porcelain or tin washbasin 

 makes a good arena, but a rectangular glass receptacle, such as a battery 

 jar, affords a better view. The fish immediately approach each other and indulge 

 in a preliminary display of spread fins, expanding gill membranes, and color 

 waves, A common sparring position finds the fishes side by side with the 

 heads pointing in the same direction and with one fish slightly behind the other. 

 This position may be held for a period varying from a few seconds to several 

 minutes. Then, in quick succession, the fishes attack, their movements being 

 so swift that the human eye can hardly follow the actual impact of the teeth, and 

 the assaults are repeated with short intermissions, during which the same 

 sparring attitude is taken. 



The most common points of attack are the anal, caudal, and dorsal fins. The 

 ventral and pectoral fins may be practically untouched at the end of a protracted 

 encounter, but may receive early attention from one or both contestants. The 

 vertical fins, however, are always involved. The first evidence of a spirited en- 

 counter is likely to be torn or split fins. As the contest proceeds, there may be 

 extensive loss of fin substance, and with well-matched fishes the vertical fins may 

 utimately be reduced to mere stubs. 



The loss or extensive damage of the fins impairs the swimming, steering, and 

 balancing powers and hence places a fish at a disadvantage, but in evenly matched 

 fishes this is not likely to be a final factor in deciding the issue. 



Another point of attack is the side of the body. Single scales or clumps of 

 scales may be loosened or detached by a quick nipping act, but in many contests 

 this kind of injury may not occur. Exceptionally the gill covers may be bitten 

 and slight injury may be done to the gills. 



An interesting variation in fighting tactics ensues when the fishes come to- 

 gether in a head-on assault and lock jaws. With their jaws firmly locked and 

 their bodies extended, the fishes struggle while partly or completely rotating on 

 their long axis. In my observations, the locked-jaw attack was always com- 

 paratively brief and was invariably terminated by the fishes settling to the 

 bottom and remaining perfectly still for, say, 10 to 20 seconds. The hold was 

 then broken and the fishes rapidly sought the surface for air, and then resumed 

 their ordinary tactics. The locked-jaw position interferes with respiration and 

 lasts only as long as the fishes can resist the call of the system for extra oxygen. 



During the short interludes in fighting when the demand for oxygen forces the 

 fishes to go to the surface for gulps of air, attacks are always suspended. I 



