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Fishery Bulletin 92(1), 1994 



Figure 1 



Locations seined in Southeast Alaska and British Columbia 

 in 1983 and 1984. The delineation between northern and 

 southern Southeast Alaska is indicated by the dotted line 

 (running along 56°N lat.). 



We sampled in Southeast Alaska during three 

 periods: 6 August-3 September 1983 (hereafter des- 

 ignated August 1983), 9-24 July 1984, and 1-30 

 August 1984. Sampling in British Columbia was 

 conducted 1-6 July 1984. 



Survey stations in outside waters were located 

 along transects perpendicular to shore (Fig. 1). The 

 nearshore station of each transect was as close to 

 land as net depth and safety permitted. Stations 

 were usually sampled progressively offshore at 5.6 

 km (3 nautical miles [nmi]) intervals in 1983 and 

 at 9.3 km (5 nmi) intervals in 1984. Sampling gen- 

 erally did not extend beyond 37 km offshore except 

 in Southeast Alaska in August 1984, when transects 



extended as far as 74 km offshore. Distances 

 are rounded to the nearest 1 km in the text. 

 In large passages in the inside waters, sets 

 were often made along transects near the en- 

 trance to outside waters (Fig. 1). Multiple sets 

 were also made in clusters in the larger inlets. 



Gear 



Stations were sampled with table and 

 drum seines as described by Browning 

 (1980). The 28-m NOAA RV John N. Cobb 

 fished a table seine in August 1983 and 

 August 1984; the 24-m FV Bering Sea 

 fished a drum seine in July 1984. Sets were 

 made at predetermined locations without 

 reference to visual or instrument sightings 

 of fish. All sets were round hauls: the net 

 was set in a semi-circle, held open 3—5 

 minutes, closed, pursed, and retrieved by 

 means of a hydraulic power block (table 

 seine) or a hydraulic roller (drum seine). 

 Only catches from effective seine sets are 

 listed (Table 1). 



Although the seines differed in size, 

 mesh, and area enclosed, the two nets were 

 assumed to be comparable in their ability 

 to capture juvenile salmon. The table seine 

 was 455 m long; depth tapered from 37 m 

 in the wing to 11 m in the bunt; web sizes 

 (stretch mesh) were 89 mm and 57 mm in 

 the wing, and 25 mm in the bunt. The 

 drum seine was 503 m long, 46 m deep, and 

 had 32-mm mesh in the wing, and 25 mm 

 in the bunt. Depths fished were assumed 

 to be adequate for sampling juvenile pink 

 (O. gorbuscha), chum (O. keta), sockeye (O. 

 nerka), and coho (O. kisutch) salmon, which 

 usually occupy the upper 10 m of the wa- 

 ter (Manzer, 1964; Godfrey et al., 1975; 

 Hartt, 1975). To compensate for the larger 

 surface area enclosed by the drum seine 

 (20,150 m 2 ) compared to the table seine (16,467 m 2 ), 

 drum seine catches (July 1984) were reduced during 

 analyses by 18.3% to standardize the catch per unit 

 of effort (CPUE). This standardization caused the July 

 1984 catches reported to be sometimes less than the 

 number of fish measured for size that period. 



Catch processing and analysis 



The catch was processed aboard ship and in the 

 Auke Bay Laboratory. The number of juvenile 

 salmon captured in each set was counted if the catch 

 was small (i.e., <100 fish) or estimated gravimetri- 

 cally if the catch was large. Up to 100 salmon from 

 each set were preserved in 10% formalin in seawater 



