FISHERY BULLETIN: VOL. 87, NO. 3, 1989 



40 



Figure 2. — Outmigration of juvenile chum salmon, stream temperatures, 

 and stream height-velocity of Whiskey Creek (1984, 1985, 1986) and Jack- 

 son Creek (1986). Solid triangles indicate dates of hatchery releases. 



salmon in the upper bay increased only once in 

 all three years when temperatures exceeded 

 16°C(Fig."5, 1985). 



Schools of chum salmon were sometimes ob- 

 served in shallow water and variability in the 

 catches of juvenile chum salmon per set was 

 high. The median number of chum caught per set 

 during a sampling date, all stations combined, 

 ranged from to 280. A total of 90 pairs of beach 

 seine sets were made during the three years. 



The mean (± standard deviation) of the quotient 

 of the largest to smallest numbers of chum 

 caught in the 47 pairs of two sets (each set con- 

 taining fish) was 5.9 ± 8.8. This indicates that 

 juvenile chum salmon were aggregated in 

 Netarts Bay. 



Median catches of juvenile chum salmon dur- 

 ing high tide generally exceeded catches at low 

 tide in March and April, and catches at low tide 

 were greater than high tide during May and 



558 



