1909.] - The Life History of the Pacific Salmon. 29 



in it and the bright silvery sheen almost disappears; the blue of the back 

 gives place to a blood -red colour and the sides also become red, though of 

 a darker shade. In the males a further change occurs in that both the 

 upper and lower jaws elongate to form a snout and become greatly hooked, 

 large teeth at the same time developing upon the terminal portions of the 

 jaws, so that from its original graceful form the head assumes a decidedly 

 grotesque appearance. The body also changes somewhat in shape, be- 

 coming deeper and flatter, especially in the region of the shoulders, and in 

 the Humpback salmon a distinct hump appears upon the back just behind 

 the head, and may reach a considerable size. 



But the changes are not confined to the external form and colouration ; 

 the internal organs are also materially affected. So long as the fish 

 remain in salt water they feed voraciously, but as soon as they enter fresh 

 water they practically cease to feed and, unlike the Atlantic salmon 

 will not as a rule rise to a fly and hence possess little interest for anglers. 

 Indeed, it is said that we owe the loss of certain islands in the Gulf of 

 Georgia to this peculiarity of the Pacific salmon. For, so the story goes, 

 it being a matter of discussion, during the framing of one of the boundary 

 treaties, as to which side of the islands the boundary line should pass, 

 the British Government instructed the admiral in comm.and of the war- 

 ships at the time on the Pacific coast to visit the islands and report as to 

 the advisability of disputing their possession. The admiral, hearing that 

 salmon occurred in the streams of the islands and being a keen fisherman, 

 looked forward to combining some excellent sport with the performance 

 of his duties and was so disappointed by his failure to get the fish to rise to 

 his flies that he reported unfavourably regarding the islands and advised 

 his government that it was not worth while to insist upon their retention. 



The cessation and long continued abstinence from feeding brings 

 about a marked loss of weight, so that the fish when they arrive at the 

 spawning grounds are in this respect, as well as in general form, greatly 

 fallen from their former estate. I cannot give any figures showing the 

 extent of this loss of weight in the Sockeye, but may quote an observation 

 made by Rutter* on three Spring salmon which were captured at Rio 

 Vista, not far from the mouth of the Sacramento River, and, after care- 

 ful weighing, were marked so that they could be recognized if taken again 

 and were then released. Sixty-four and fifty-six days later two of these 

 fish were taken at the Mill Creek fishery and after sixty-six days the third 

 was taken at Battle Creek, and when again weighed these fish were found 

 to have lost respectivel}^ twenty-six per cent., fifteen per cent, and twenty- 



*C. Rutter. Bull. U.S. Fish Commission. XXII. 1903. 



