SWORDFISH 



shore banks. We know that the temperature of the 

 water in these locaHties and at that depth is sure to 

 be less than 40° Fahr. How is this fact to be recon- 

 ciled with the known habits of the fish, that it pre- 

 fers the warmest weather of summer and swims 

 at the surface in water of temperature ranging from 

 55° to 70°, sinking when cool winds blow below? 

 The case seemed clear enough until the inconvenient 

 discovery was made that swordfish are taken on 

 bottom trawl lines. In other respects their habits 

 agree closely with those of the mackerel tribe, all 

 the members of which seem sensitive to slight 

 changes in temperature, and which, as a rule, pre- 

 fer temperature in the neighborhood of 50° or more. 



The appearance of the fish at the surface depends 

 largely upon the temperature. They are seen only 

 upon quiet summer days, in the morning before ten 

 or eleven o'clock, and in the afternoon about four 

 o'clock. Old fishermen say that they rise when the 

 mackerel rise, and when the mackerel go down they 

 go down also. 



Regarding the winter abode of the swordfish, con- 

 jecture is useless. I have already discussed this 

 question at length with reference to the menhaden 

 and mackerel. With the swordfish the conditions 

 are very different. The former are known to spawn 

 in our waters, and the schools of young ones follow 

 the old ones in toward the shores. The latter do 

 not spawn in our waters. We cannot well believe 

 that they hibernate, nor is the hypothesis of a so- 

 jovmi in the middle strata of mid-ocean exactly 

 tenable. Perhaps they migrate to some distant 

 r^on, where they spawn. But then the spawning- 



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