FISHERY BULLETIN: VOL. 85, NO. 3 



these years) indicate that most sockeye may have 

 migrated southwest from a relatively southerly 

 position offshore and returned to the Fraser River 

 via the Strait of Juan de Fuca. In 1980 and 1981 

 the largest sockeye catches were made near the 

 north of Vancouver Island in areas 11 and 27 (Fig. 

 4). In these years 70 and 67% of the Fraser sock- 

 eye migrated through Johnstone Strait. In 1983 

 an extreme situation prevailed: most of the sock- 

 eye salmon were caught in area 11 (Queen Char- 

 lotte Sound) and 80% of the fish migrated via the 

 northern route (Fig. 4). 



From these results we conclude that the propor- 

 tions of Fraser River sockeye salmon returning 

 via the northern and southern routes are gener- 

 ally associated with the area where the fish make 

 their landfall (see also Tully et al. 1960; Henry 

 1961; IPSFC 1979-1984). If the majority of Fraser 

 sockeye approach the coast west of Vancouver Is- 

 land, then most will continue to migrate via the 

 Strait of Juan de Fuca. However, when landfall 

 occurs north of Vancouver Island in the Queen 

 Charlotte Sound area, most homeward migrating 

 Fraser sockeye will travel through Johnstone 

 Strait. 



North Coast Salmon 

 Tagging Project 



During 1982 and 1983, Canada and the United 

 States tagged sockeye salmon along the coast of 

 northern British Columbia and southeastern 

 Alaska to determine interception rates in the 

 commercial fisheries of both countries near the 

 boundary. The results of these studies provide ad- 

 ditional information on migratory routes of this 

 species along the North American coast. In 1982, 

 40,556 and in 1983, 23,052 maturing sockeye 

 salmon were tagged in several places in south- 

 eastern Alaska and northern British Columbia 

 (Fig. 5) (B. RiddelH). Most of these fish were head- 

 ing for spawning rivers in southeastern Alaska 

 and the Nass and Skeena Rivers of northern 

 British Columbia. However, a number of sockeye 

 salmon, 24 in 1982 and 126 in 1983, were recov- 

 ered in the commercial fishery around Vancouver 

 Island. We assume that most of these were Fraser 

 River fish because more than 90% of sockeye 

 salmon captured in southern British Columbia 

 belong to Fraser River stocks. 



Of the sockeye salmon tagged in the north, 9 



4B. Riddell, Pacific Biological Station, Nanaimo, B.C. V9R 

 5K6, Canada, pers. commun. 1985. 



times more were recovered in the Vancouver Is- 

 land area in 1983 than in 1982 (Fig. 5), despite 

 the fact that the total run of sockeye to the Fraser 

 River in 1982 (13,933,000) was more than twice 

 as large as in 1983 (5,167,000; IPSFC 1983, 1984). 

 This indicates that in 1983 a greater proportion of 

 Fraser River sockeye made landfall north of Van- 

 couver Island than in 1982. This was reflected in 

 the diversion rates through Johnstone Strait of 80 

 and 22% respectively for the 2 years (Figs. 1,4). 

 The results also show that relatively 9 (1982) to 

 13 (1983) times more sockeye were recovered in 

 the Vancouver Island area from the outside 

 (Noyes and Queen Charlotte Islands, and Cape 

 Muzon) than from the inside (Clarence Strait and 

 Areas 3, 4, and 5) tagging operations (Fig. 5). We 

 suggest that the southern British Columbia sock- 

 eye primarily migrated along the west coast of 

 the Queen Charlotte Islands during their migra- 

 tion south. However, some entered Dixon En- 

 trance in 1983 and travelled through Hecate 

 Strait towards the Fraser River, as indicated by 

 recoveries from inside tagging locations. 



The findings from the North Coast Tagging 

 Project support the evidence presented earlier 

 that coastal migratory routes of Fraser River 

 sockeye can vary considerably from year to year 

 and that during years of high diversion through 

 Johnstone Strait the returning sockeye make 

 landfall farther north. Analysis of catches, run 

 timing, and stock composition led the Pacific 

 Salmon Commission to a similar conclusion sev- 

 eral years ago (IPSFC 1983). 



In summary, our analysis of the INPFC, West 

 Coast Troll, and North Coast Tagging data sets 

 indicates that Fraser River sockeye salmon re- 

 turning from ocean feeding grounds approach 

 Vancouver Island from the west and northwest. 

 The area of landfall varies yearly from the west 

 coast of Vancouver Island to more northern re- 

 gions in Queen Charlotte Sound. Moreover, the 

 area where most salmon reach the coast is 

 strongly correlated with the proportion that en- 

 ters the Strait of Georgia via the southern or 

 northern routes. 



Migratory Routes and 

 Oceanographic Conditions 



A coastal approach north of Vancouver Island 

 results in a higher proportion of fish moving 

 through Johnstone Strait, while an approach far- 

 ther south, along the west coast of Vancouver Is- 

 land, directs the fish to the Fraser River through 



460 



