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Fishery Bulletin 88(4). 1990 



for steelhead. Steelhead were captured as far south as 

 northern California during the extended cruise of July 

 1984. 



The highest average catches of both cutthroat and 

 steelhead trout occurred 37.2-46.3 km offshore (Table 

 3). Low catches of both species were found in the zone 

 closest to shore (<9.3 km). Catches of cutthroat were 

 high 37.2-46.3 km offshore only in May and June 1985, 

 when juvenile coho salmon were also found far offshore 

 (Fisher and Pearcy 1985). In other years highest cat- 

 ches of cutthroat were 9.4-27.8 km offshore, inshore 



of maximal steelhead catches. The zone of highest 

 average catches for all years was characterized by a 

 mean sea surface temperature of 13.4°C (standard 

 deviation, SD, 1.4), mean surface salinity of 28.6"/oo 

 (SD 4.3) and secchi depth of 5.4 m (SD 2.2). The low 

 surface salinities in areas where steelhead and cut- 

 throat trout were abundant indicate the influence of 

 freshwater, often the Columbia River plume. Detailed 

 spatial information on catches is given by Pearcy and 

 Fisher (In press) by cruise. 



