The results of the tagging in the nearshore areas on 

 the west and east sides of inner Bristol Bay also show- 

 ed an increase in stock segregation (Fig. 22). 

 Nushagak Bay sockeye salmon became the most 

 abundant stocks on the west side of inner Bristol Bay, 

 and Ugashik and Egegik River fish the most abundant 

 stocks on the east side of the inner bay. From this dis- 

 tribution, I concluded that Naknek, Kvichak, and 

 Alagnak River fish mostly remained in the offshore 

 waters until they reached Kvichak Bay in the area 

 northeast of Middle Bluff. 



The various sockeye salmon stocks in the run to 

 Nushagak Bay became segregated to a certain extent 

 before they entered that bay. The Igushik River stock 

 was most abundant in the nearshore area off Cape 

 Constantine and along the west side of Nushagak Bay 

 to the Igushik River mouth. The data suggest that 

 Snake River fish were most abundant along the west 

 side and in the middle of Nushagak Bay. The Wood 

 River stock was most abundant on the east side of the 

 bay, indicating this stock and probably the Nushagak 

 River stock enter en masse on the east side and in the 

 middle of Nushagak Bay. 



Ugashik sockeye salmon were also declining in 

 abundance in the offshore waters of outer Bristol Bay 

 and increasing in abundance nearer to shore on the 

 east side of inner Bristol Bay. South of lat. 58°N 

 Ugashik River fish increased in abundance, becoming 

 most abundant in the nearshore area south of the en- 

 trance to Ugashik Bay. 



Sockeye salmon bound for the Egegik River system 

 were declining in abundance in the offshore waters of 

 outer Bristol Bay as far seaward as long. 159°W. They 

 apparently reached the coastal area in greatest abun- 

 dance between Middle Bluff and lat. 58°N. 



Naknek and Kvichak River sockeye salmon were 

 also segregated from each other by the time they 

 entered Kvichak Bay. Fish bound for the Kvichak 

 River were most abundant on the west side and in the 

 middle of Kvichak Bay. Naknek River fish were most 

 abundant in the nearshore waters on the east side of 

 Kvichak Bay northeast of Middle Bluff. 



SUMMARY 



1. The results of the exploratory fishing operations 

 in the eastern Bering Sea and outer Bristol Bay show- 

 ed that the main migration route of Bristol Bay 

 sockeye salmon is in the offshore waters of the south 

 half of the entrance to the bay and in the south half of 

 the bay itself. This migration route is illustrated on a 

 chart of the area. 



2. Offshore tagging studies showed that there was 

 little segregation of the individual stocks of Bristol 

 Bay sockeye salmon in the eastern Bering Sea and 

 outer Bristol Bay as far as a line between Port MoUer 

 and Cape Newenham. Toward the head of the bay 

 from this line, there was a progressive segregation of 

 sockeye salmon stocks according to their river system 

 of origin. This segregation appeared to begin while 



these fish were still as much as 200 km from the 

 mouths of their home-river systems. 



3. Inshore tagging studies showed a continuation of 

 stock segregation toward the head of Bristol Bay. 

 Those sockeye salmon stocks originating in the river 

 systems of Nushagak Bay became most abundant on 

 the west side of inner Bristol Bay. They appeared to 

 be somewhat segregated before entering Nushagak 

 Bay. Ugashik and Egegik River sockeye salmon 

 became the most abundant stocks on the east side of 

 the inner bay. Naknek, Kvichak, and Alagnak river 

 sockeye salmon stocks remained offshore until they 

 reached Kvichak Bay in the area northeast of Middle 

 Bluff. These results are illustrated on a chart of 

 Bristol Bay. 



LITERATURE CITED 



BARNABY, J. T. 



1952. Offshore fishing in Bristol Bay and Bering Sea. U.S. 

 Fish Wildl. Serv., Spec. Sci. Rep. Fish. 89, 30 p. 

 FRENCH, R. 



1963. Salmon distribution and abundance on the high seas. 

 Int. North Pac. Fish. Comm., Annu. Rep. 1961:92-101. 

 FRENCH, R., D. CRADDOCK, R, BAKKALA, J. DUNN, and K. 

 THORSON. 



1967. Ocean distribution, abundance, and migrations of 

 salmon. Int. North Pac. Fish. Coram., Annu. Rep. 1966: 

 78-89, 



GILBERT, C. H. 



1923. Experiment in tagging adult red salmon, Alaska Penin- 

 sula fisheries reservation, summer of 1922. U.S. Bur. Fish., 

 Bull. 39:39-50. 



HARTT, A. C. 



1962. Movement of salmon in the North Pacific Ocean and 

 Bering Sea as determined by tagging, 1956-1958. Int. North 

 Pac. Fish. Comm., Bull. 6, 157 p. 



1966. Migrations of salmon in the North Pacific Ocean and 

 Bering Sea as determined by seining and tagging, 1959-1960. 

 Int. North Pac. Fish. Comm., Bull. 19, 141 p. 

 HOKKAIDO UNIVERSITY, THE FACULTY of FISHERIES. 



1968. Data record of oceanographic observations and explora- 

 tory fishing. No. 12, 421 p. 



1970. Data record of oceanographic observations and explora- 

 tory fishing. No. 14, 429 p. 

 INTERNATIONAL NORTH PACIFIC FISHERIES COMMIS- 

 SION. 



1959. Distribution and racial sampling of salmon on the high 

 seas. Int. North Pac. Fish. Coram., Annu. Rep. 1958:74-78. 



1960. Distribution and racial sampling of salmon on the high 

 seas. Int. North Pac. Fish. Comm., Annu. Rep. 1959:79-85. 



KASAHARA, H. 



1963. Salmon of the North Pacific Ocean, Part I. Catch sta- 

 tistics for North Pacific Salmon. Int. North Pac. Fish. 

 Coram., Bull. 12, p. 7-82. 



KONDO. H., Y. HIRANO, N. NAKAYAMA, and M. MIYAKE. 

 1965. Offshore distribution and migration of Pacific salmon 

 (genus Oncorhynchus) based on tagging studies (1958-1961). 

 Int. North Pac. Fish. Coram., Bull. 17, 213 p. 

 KOO, T. S. Y. 



1962. Age designation in salmon. Univ. Wash., Publ. Fish, 

 New Ser. 1:37-48. 



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