FISHERY BULLETIN: VOL. 75, NO. 2 



1966, Pacific ocean perch production has fallen 

 drastically in several areas fished by these North 

 American trawlers, largely because of excessive 

 catches by Japanese and Soviet fleets. 



Japanese and Soviet trawl fisheries for Pacific 

 ocean perch began in the Bering Sea about 1960 

 and expanded southward into the eastern Gulf of 

 Alaska in 1963. The Soviet fleet operated 

 throughout the Queen Charlotte Sound-Oregon 

 region by 1965, and they were joined by Japanese 

 trawlers in 1966. Catches from the Oregon-Queen 

 Charlotte Sound region were quite high initially 

 (Figures 1 through 3), but the stocks were far too 

 limited to sustain these harvests. By 1969, S. 

 alutus stocks were severely depleted throughout 

 the Oregon- Vancouver Island region (Figures 1, 

 2). Production in the International North Pacific 

 Fisheries Commission (INPFC) Vancouver and 

 Columbia areas plummeted from 39,000 metric 

 tons in 1967 to 6,000 metric tons in 1969 (an 85% 

 decline), and catch per hour by North American 

 trawlers declined 45% during the same period 

 (Westrheim et al. 1972). Data on catch per unit 

 effort (CPUE) suggest that the exploitable 

 biomass of Pacific ocean perch in the Vancouver- 



0.6 



0.4 



0.2 <-> 



56 



Columbia region has changed little since 1969, 

 despite the fact that a series of relatively strong 

 year classes have recruited to the fishery. 



Pacific ocean perch stocks in Queen Charlotte 

 Sound were affected less drastically by fishing 

 than those in the Oregon-Vancouver Island re- 

 gion. Biomass estimates and CPUE data (Wes- 

 trheim et al. 1972) indicated that S. alutus were 

 initially more abundant in the former area and 

 that they did not undergo such intensive exploita- 

 tion. During 1966-68, production declined 50% 

 while CPUE of Washington trawlers declined 

 36%. Fishing effort was reduced substantially 

 after March 1971, when most of Queen Charlotte 

 Sound was declared to be an exclusive Canadian 

 fishing zone. Bilateral agreements between 

 Canada and the United States allowed the tradi- 

 tional United States fishery for S. alutus to con- 

 tinue, but Japanese and Soviet fishing was prohib- 

 ited. Recent information, however, indicates that 

 in 1974, large catches of Queen Charlotte Sound 

 Pacific ocean perch were made by Japanese vessels 



56 



60 



65 



70 



20 



E 

 m 

 O 



£ io 



CPUE 



CATCH 



| 



JAPAN 

 U.S.S.R 



CANADA - U.S. 



60 '65 



YEAR 



'70 



0.8 



0.6 



0.4 



0.2 



FIGURE 1.— Catch and CPUE data for Pacific ocean perch in the 

 INPFC Columbia area (from Westrheim et al. 1972). 



370 



FIGURE 2.— Catch and CPUE data for Pacific ocean perch in the 

 INPFC Vancouver Area (from Westrheim et al. 1972). 



