This report summarizes the data we now rec- 

 ognize as bearing on the question of optimum 

 escapement. In it we recommend (where pos- 

 sible) optimum escapement for each of the sock- 

 eye salmon river systems in southwestern 

 Alaska and discuss the factors that affect those 

 levels. The recommendations are the best that 

 we can prepare at this time. They are not the 

 last word — that must await a more detailed un- 

 derstanding of the life of young sockeye salmon. 



Commercial fishing for sockeye salmon in 

 southwestern Alaska started in 1884, and the 

 annual catch ro.se rapidly to more than 10 mil- 

 lion fish by 1900 and was rarely le.ss than this 

 until after 1940.^ Between 1913 and 1938 the 

 annual production in the Bristol Bay area alone 

 exceeded 20 million fish 10 times. The record of 

 24,700.000 was in 1938. More than half of the 

 catch usually came from the Naknek-Kvichak 

 district, where the fishery produced a record 

 catch of almost 21 million fi.sh in 1938. 



During many of the years that the Fedei-al 

 Government managed the sockeye salmon fish- 

 eries of southwestern Alaska, desired escape- 

 ments in the major river systems were estab- 

 li.shed by law. The White Act of June 26, 1924, 

 declared the intent of Congress to limit the catch 

 to 50 percent of the returning salmon — that is, 

 one fish in the escapement for each one in the 

 catch. As our knowledge of the life history of 

 sockeye salmon increased, it became apparent 

 that in some years the stocks were so small that 

 the entire returns were not adequate to use fully 

 the spawning grounds or nursery areas ; in other 

 years the returns were so large that escape- 

 ments of 50 percent were obviously excessive. 

 This provision of the act was repealed on Sep- 

 tember 4, 1957.^ 



In autumn 1960 it became evident that a 

 major research program was needed to supply 

 additional biological information to be used in 

 the management of the sockeye salmon and pink 

 salmon (0. gorbuscha) of Alaska. 



This need for information was emphasized by 

 the escapement of more than 3 million adult 

 sockeye salmon to the rivers of the Nushagak 

 fishing district and more than 2 million to the 

 Naknek River in 1959, and an escapement of 



almost 15 million to the Kvichak River in 1960. 

 These possibly excessive escapements again 

 raised many questions about optimum escape- 

 ments. In spring 1961, the Secretary of the U.S. 

 Department of the Interior submitted a revised 

 budget in which he requested an increase of 

 $1' -J million for an intensified .salmon research 

 program in Alaska. 



The study of sockeye salmon was undertaken 

 by the BCF (Bureau of Commercial Fisheries 

 Auke Bay Biological Laboratory). About half 

 the funds and research were contracted to the 

 FRI (Fisheries Research Institute, University 

 of Washington). The two agencies together 

 planned several projects on the major sockeye 

 salmon systems.^ Both organizations had his- 

 torically worked in specific sockeye salmon river 

 systems ; they concentrated their efforts in these 

 areas during this study. The FRI worked on the 

 systems tributary to Nushagak Bay (the Igu- 

 shik. Snake, Wood, and Nuyakuk systems) on 

 the mainland, the Kvichak sy.stem at the head of 

 the Alaska Penin.sula, and the Chignik system 

 on the Gulf of Alaska side of the Peninsula. The 

 BCF worked on the Alagnak, Naknek, Egegik, 

 and Ugashik systems of the Alaska Peninsula 

 and the Karluk system on Kodiak Island (fig. 

 2). By mutual agreement, one agency or the 

 other analyzed historic records of catch and es- 

 capement for individual systems. 



The intensified program began in April 1961, 

 and field work continued through the summer of 

 1962. Most of the techniques used by the two 

 organizations were standardized. Field research 

 guides and standardized data sheets were pre- 

 pared. 



The satisfactory execution of this large pro- 

 gram required the effort of many biologists. The 

 research responsibilities within the BCF and 

 FRI were as follows. 



For the BCF — George Y. Harry, Jr., and 

 Charles J. DiCostanzo, assisted by Wilbur L. 

 Hartman, were responsible for general planning 

 and supervision. DiCostanzo directly supervised 

 the compilation and analysis of the data on the 

 historical and current catch and escapement of 

 adults and on the records of counts of smolts. 

 Hartman supervised the limnological research 



^ Extensive statistics on the catch and pack are available in Rich and 

 Ball (1928), Simpson (1960). and in annual publications such as the 

 Pacific Fisherman Yearbook and the Statistical Yearbook of the 

 International North Pacific Fisheries Commission. 



= Public Law 85-296. 



* Each lake or group of connected lakes and its outlet to the ocean 

 is termed a "system" and designated in this report by the name of the 

 outlet or trunk river. For example. Amanka and Ualik Lakes are con- 

 nected to the ocean through the Igushik River, and the system is, 

 therefore, called the Igushik. 



SOCKEYE SALMON IN MAJOR RIVER SYSTEMS IN SOUTHWESTERN ALASKA 



407 



