48 ■ FISHEEIES OF ALASKA, 190b, 



It is only on the supposition that 7,200,000 salmon are inadequate 

 to cause 7,200,000 + 6,400,000, or 13,600,000, to return to Nusliagak 

 Bay at the end of the next reproductive period, that a lower incre- 

 ment than 88 per cent may be inferred. It is perhaps conceivable 

 that during the last nine years, in which the average take has been 

 over 5,000,000, varying from nearly 3,000,000 to nearly 7,000,000, a 

 larger average yearly number in some way escaped to breed than in 

 1908. In this case the increment percentage would be much lowered, 

 the more since this increased escape would have been coincident 

 with, in most years, a decreased catch. 



It is, however, difficult to believe that the average spawning 

 escape has been for some years greater than 7,000,000. The assump- 

 tion that the lesser packs of these years indicate lesser escapes is 

 probably the true one. The cannery operations tend toward a 

 maximum pack under the conditions of each season — a small pack 

 meaning a small run and small escape, a large pack necessarily a 

 large run and probably a large escape. That the escape of 1908 is 

 larger than the average for nine years and larger than that for any 

 single year save 1905 is extremely probable. Unless the ancestral 

 run dates much further back than all experience indicates, it follows 

 from this that the increment of red salmon acting during the past few 

 years may be reasonably inferred to be little, if any, less than 100 

 per cent, and may be considerably greater. 



While this is the trend of the figures at hand, they are not, of course, 

 to be accepted as establishing any general principle. But careful 

 consideration should be given to the possibilities that lie in observa- 

 tions of this sort when they are made sufficiently complete. It 

 would seem certain that their result would in the end be the deter- 

 mination of the natural increment of the red salmon during commer- 

 cial fishing for the region in question — in other words, the size of the 

 run entering the bay, the minimum number which should be reserved 

 for breeding, and the number which may be taken without injury to 

 the future supply and possibly to its benefit. Fixed within rather 

 wide limits at first, these important and interdependent factors 

 would each year tend to become more accurately fixed. They might 

 finally afford the basis for a practical policy. 



Migration movements of salmon in the river. — The red salmon run 

 in the bay may be said to have begun July 1. The first impulses of 

 importance from this run reached the foot of Lake Aleknagik not 

 earlier than July 7 and not later than July 10. It evidently takes a 

 week or ten days for the schools to make the journey from the mouth 

 of the bay to the foot of the lake, a distance of some 50 miles. In the 



uddy waters of the lower river where the tide ebbs and flows they 

 probably to some extent swim back and forth with the tides. At least 

 they do not make the same progress upstream that they do later when 



