STATISTICAL RECORDS AND COMPUTATIONS ON RED 

 SALMON (Oncorhynchus nerka) RUNS IN THE NUSHAGAK 

 DISTRICT, BRISTOL BAY, ALASKA, 1946-59 



by 



Ole A. Mathisen, Robert L. Burgner, and 

 Ted S. Y. Koo, Research Associate Professors 



Fisheries Research Institute, 



College of Fisheries, University of Washington 



Seattle, Washington 



ABSTRACT 



This paper presents the basic biological statistics collected from the catch 

 and espapement of red salmon runs in the Nushagak District of Bristol Bay, Alaska, 

 for the years 1946-59. Tables of preliminary computations showing relationships 

 between the adult escapement and the returning run and between the seaward mi- 

 gration of juveniles and the returning run are also given. 



INTRODUCTION 



In 1946, under the direction of William F. 

 Thompson, the Fisheries Research Institute 

 began a study of the red salmon (Oncorhynchus 

 nerka) runs in the Nushagak District, Bristol 

 Bay, Alaska. Fluctuations in population levels 

 were of primary concern. Consequently, sta- 

 tistics relating each year's spawning escape- 

 ment to numbers and age composition of 

 progeny returning in subsequent years were 

 needed. We learned in the first year of the 

 study that the gill net fishery was selective 

 on age, sex, and size and therefore made 

 plans to obtain accurate statistics of numbers, 

 sex ratio, and age composition of the runs by 

 sampling both the escapement and the com- 

 mercial catch. A sampling system was or- 

 ganized by Thompson in 1946 and is still used 

 in the Bristol Bay area. 



In this report, we present the basic statistics 

 collected from the catch and escapement from 



1946 to 1959 and the computations which show 

 relationships between the adult escapement 

 and the returning run, between the seaward 

 migration of juveniles and the adult mn, and 

 other pertinent data. 



A thorough understanding of these relation- 

 ships is of great importance to the fishing 

 industry of Bristol Bay in establishing a 

 basis for reliable advance predictions of the 

 numbers of salmon returning each year to 

 the fishery. The information in this paper 

 also provides complete and detailed informa- 

 tion on a particular salmon stock, which will 

 be useful to scientists attempting to under- 

 stand annual fluctuations in any stock of 

 salmon. 



Information presented in this report is in 

 tabular and graphical form. Copies of the 

 original data are stored with the Fisheries 

 Research Institute, College of Fisheries, Uni- 

 versity of Washington. 



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