Snake and Nushagak Rivers, too, occur farther 

 offshore in the Cape Constantine area. Therefore, 

 these three stocks must enter Nushagak Bay in the 

 middle and on the east side of the bay during migra- 

 tion to their home-river systems. 



The results of the 1959 tagging in Nushagak Bay 

 suggest that a substantial number of sockeye salmon 

 tagged near the middle of the bay (site 2 — Fig. 17) 

 were bound for the Snake River system. The propor- 

 tion of tagged fish observed in the escapements of the 

 Wood and Igushik Rivers was significantly lower for 

 fish from site 2 than sites 1, 3, and 4 (Appendix Table 

 7). Because the proportion of fishery recaptures of 

 tagged fish was essentially the same for all four sites 

 (Appendix Table 6), removal of tagged fish by the 

 fishery was not regarded as the cause of the lower 

 proportion of tagged fish from site 2 in the escape- 

 ment. Fishery recaptures of fish tagged at site 2 were 

 equally abundant on the east and west sides of 

 Nushagak Bay (Fig. 21), even though the fishing effort 

 on the east side of Nushagak Bay was considerably 

 greater than on the west side. This indicates that 

 more fish tagged at site 2 were on the west side than 

 on the east side and consequently more of the fish 

 should have escaped the fishery to be observed in the 

 spawning escapement. A plausible explanation for 

 their absence in the escapement is that they went to 

 some river system not adequately searched for tagged 

 fish. 



Reliable observations of tagged sockeye salmon 

 were not made in the Nushagak River escapement, 

 but five tags were recovered in the personal-use gill 

 nets in the main Nushagak River. The personal-use 

 fishery is well above the commercial fishery and below 

 the escapement enumeration towers. The recovered 

 fish were from taggings at sites 2, 3, and 4 (Appendix 

 Table 7) in the middle and on the east side of 

 Nushagak Bay. 



The Snake River system was not checked for tags 

 until late August, when it was discovered it had 

 received an unusually large escapement. Most of the 

 sockeye salmon in the Snake River escapement spawn 

 on the beaches of Nunavaugaluk Lake (Fig. 1). High 

 winds and rough water during a 3-day survey of this 

 lake hampered observations of the spawning fish, but 

 three tags were positively identified. Two of the fish 

 had been tagged at site 2 and one at site 3. These 

 observations are too few to be conclusive, but they do 

 suggest the distribution noted previously here, i.e. 

 Snake River fish are most abundant on the west side 

 and in the middle of Nushagak Bay. 



Synopsis: Segregation of Sockeye Salmon Stocks 

 in the Inshore Region of Bristol Bay. — In Figure 22, 

 I present a generalized picture of the probable migra- 

 tion routes of various stocks of sockeye salmon as they 

 move through Bristol Bay after leaving the Bering 

 Sea. Additional tagging is needed in both the near- 

 shore and offshore waters on the north and west sides 

 of Bristol Bay. 



Figure 22.— General distribution of Bristol Bay stocks of 

 sockeye salmon, showing areas of greatest stock abundance. 



SYNOPSIS OF DISTRIBUTION AND 



MIGRATORY ROUTES OF SOCKEYE 



SALMON IN THE EASTERN BERING SEA 



AND BRISTOL BAY 



There were no statistically significant differences in 

 the distributions of the major stocks of sockeye 

 salmon destined for the fishing districts of Bristol Bay 

 between long. 171° and 167°W (Fig. 11). Stocks bound 

 for Nushagak Bay appeared to be more abundant in 

 the northerly approaches to Bristol Bay, but the 

 results are inconclusive. The distribution of stocks in 

 the eastern Bering Sea between long. 167° and 161°W 

 also remains open to question. In the area between 

 Port Moller and Cape Newenham, however, stocks 

 appeared to become segregated into those destined for 

 rivers entering on the west and those entering on the 

 east sides of Bristol Bay. Sockeye salmon migrating to 

 Kvichak Bay were abundant in the offshore waters in 

 the southern half of Bristol Bay. Stocks bound for 

 Nushagak Bay were abundant in the offshore waters 

 farther north. Stocks bound for the Ugashik and 

 Egegik Rivers declined in abundance in the offshore 

 waters and increased near to shore on the east side of 

 Bristol Bay. The tagging in outer Bristol Bay between 

 long. 161° and 158°30'W showed that stock segrega- 

 tion continued toward the head of Bristol Bay (Fig. 

 22). 



24 



