Figure 1. — Principal sockeye salmon river systems in Bristol Bay. 



reduced the size of the area where fishing is permitted 

 and have confined the fishing fleets closer to the river 

 mouths. The earliest changes were made on the large- 

 ly intuitive assumption that the fish nearest to a river 

 mouth were fish produced in that river system. 



To establish a more scientific basis for setting up 

 district boundaries, mark-and-recovery experiments 

 which defined areas of concentrations of the major 

 stocks of sockeye salmon were carried out in the inner 

 region of Bristol Bay in the 1950's and early 1960's by 

 the Bureau of Commercial Fisheries (now the 

 National Marine Fisheries Service, NOAA); the 

 Fisheries Research Institute, University of 

 Washington, Seattle; and the State of Alaska Depart- 

 ment of Fish and Game. The most extensive of these 

 were conducted from 1955 through 1959, principally 

 by the Bureau of Commercial Fisheries. In addition, a 

 considerable amount of salmon tagging and ex- 

 ploratory fishing has been carried out in outer Bristol 

 Bay and the eastern Bering Sea by the United States 

 and Japan. 



In this study, I summarize the results of the inshore 

 and offshore tagging and exploratory fishing and 



describe the probable routes followed by individual 

 river stocks of sockeye salmon during spawning migra- 

 tion from approximately long. 170° W in the Bering 

 Sea to the head of Bristol Bay. 



THE SOCKEYE SALMON FISHERY 

 OF BRISTOL BAY 



Sockeye salmon runs to Bristol Bay are among the 

 largest on the North American Continent. More than 

 50 million adult salmon have returned to spawn in the 

 river and lake systems of this area in a single year. 

 The individual stocks that make up the annual run 

 are produced in the lakes and streams of 10 major 

 river systems which discharge into the bay over a 

 shoreline distance of 193 km (Fig. 1). 



The spawning migration starts in the distant ocean 

 in early May. Salmon move directly toward the Aleu- 

 tian Islands passes from their feeding grounds in the 

 North Pacific Ocean and then eastward in the Bering 

 Sea to Bristol Bay at a rate of about 48 km per day 

 (Hartt 1962). Small numbers offish are on the fishing 

 grounds by mid-June, and the run usually reaches 



