590 U- S. BUREAU OF FISHERIES 



The results from this part of the investigation are not as yet com- 

 plete, hence it is not possible to draw any conclusions from them 

 at the present time. 



A list of all the important pink-salmon spawning streams in 

 southeastern Alaska has been compiled. The streams in this list 

 are classified according to the fishing districts in which they are 

 found, and with the tabulation of each stream is included its name 

 and location in degrees of latitude and longitude. Thus far only 

 45 streams have been surveyed in the territory. After a large num- 

 ber of streams have been surveyed, an analysis will be made of the 

 data collected during the survey of each stream. It is hoped that 

 this analysis will aid in determining some of the biological factors 

 underlying the fluctuations in the size of the pink-salmon spawning 

 populations in the streams. 



There have been numerous requests from the packers in south- 

 eastern Alaska for an extension of the fishing season. They con- 

 tend that the fishing regulations instituted in 1924 are protecting 

 the late running salmon more than the early running salmon. They 

 further contend that this unbalanced protection is tending to destroy 

 the early runs and build up the later runs with the result that the 

 bulk of the salmon are coming in later each year. In view of these 

 contentions, an analysis is being made of the daily trap catches of 

 pink salmon during the fishing seasons from 1908 to 1930 for the 

 purpose of determining the variability in the time of appearance 

 of the pink-salmon runs in southeastern Alaska both before and after 

 the institution of the fishing regulations. The results from this 

 investigation are not as yet complete. 



Bristol Bay red-salmon investigatio7i. — The scientific work in the 

 Bristol Bay region during the past year has been devoted largely to 

 a study of seasonal catch records and of the age at maturity of the 

 red saimon of the Nushagak district. Alan C. Taft has conducted 

 these investigations. 



The analysis of the catch per unit of effort at Nushagak has shown 

 that the total catch, when considered in relation to the changes in 

 total effort, is a fair indication of abundance. The study of the catch 

 per unit of effort has disclosed the same rate of decline up to 1921, 

 which was found by Kich and Ball in their work on the total catch. 

 The most serious decline was apparent in the period immediately 

 following the war and undoubtedly was due to the intensive fishing 

 during that time. Since 1921 there has been an upward trend in both 

 the total catch and the catch per unit of effort. This, probably, has 

 been due in part to the regulatory measures and closed periods insti- 

 tuted b}' the Bureau of Fisheries. 



The catch per boat was also used in a study of the correlation 

 between the annual catches at 4, 5, and 6 year intervals. The results 

 were in keeping with those of Rich and Ball, who found a high 

 correlation at 4-year intervals, but no significant positive correlation 

 at 5 or 6 year intervals. The correlation at 4-year intervals is par- 

 ticularly marked in the series of cvcles starting with 1903 and 

 including 1907, 1911, 1915, 1919, 1923," and 1927. All of these years 

 were distinctly below normal. This evidence of a high correlation 

 at 4-year intervals will be useful in the formulation of regulations 

 until an exact knowledge of the prevailing ages at maturity can be 

 obtained by a scale study. 



