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Fishery Bulletin 104(4) 



Frequency of occurrence (% FO) was determine(i for 

 each taxonomic group based on the percentage of stom- 

 achs in which that taxonomic group occurred. Percent 

 volume (% Vol) of each taxonomic group was estimated 

 visually and total weights per taxon were estimated by 

 multiplying the percent volume by the total stomach 

 weight. 



Results 



Fish catch and habitat 



Total catch of Pacific sandfish was 15,431 fish. Most 

 (99%) fish were captured with a seine: 1027 fish in July 

 (total for all years) and 14,231 larvae in March (total 

 for all years; Table 1). Total trawl catch was 173 fish; 

 2 fish in Frederick Sound in May 2001 and 171 fish in 

 Pybus Bay in May 2003. 



Most Pacific sandfish captured with a seine in July 

 and March each year were found adjacent to steep bed- 

 rock outcroppings with attached kelp (Table 1). Water 

 temperatures in summer and winter for all years were 

 about 10°C and 4°C, and salinity ranged from 30 to 

 33 PSS. Larvae were captured in March at many of 

 the same sites where juveniles were captured in July 

 (sites 1, 9-11, 14; Table 1; Fig. 2). The few adult Pacific 

 sandfish (>130 mm FL) captured with a seine in July 

 2002 and 2003 were found exclusively in low gradi- 

 ent, sandy habitat (site 1; Fig. 2). Most adult Pacific 

 sandfish were captured in Pybus Bay with a trawl at 

 least 400 m offshore of any land mass and at depths 

 between 14 and 64 m; at the depth (50 m) most fish 

 were captured, temperature was 6.5°C and salinity 

 was 31.5 PSS. 



Age and size 



Nearly all Pacific sandfish captured with a seine in July 

 (all years) were juveniles; only larvae were captured in 

 March (all years). Approximately 14,000 Pacific sandfish 

 larvae were captured in March (Table 1); mean TL was 

 16.2 mm (13.1 to 23.2 mm; Fig. 3). Of nine larvae aged 

 from March 2002, all were age-0 (Table 2). Mean FL of 

 Pacific sandfish captured with a seine in July was 86 mm 

 (62 to 150 mm; Fig. 3). Of 47 Pacific sandfish aged from 

 seine catches in July, 46 were age-1 (mean FL=75 mm) 

 and one was age-5 (FL = 135 mm) (Table 2). 



All trawl-caught Pacific sandfish were adults or sub- 

 adults. Mean FL of Pacific sandfish from trawl catches 

 was 150 mm (120 to 190 mm; Fig. 3). The 21 fish aged 

 from trawl catches in May (both years) were age-4, age- 

 5, and age-6 (mean FL = 121, 141, and 164 mm) (Table 2). 

 No age-2 or age-3 fish were captured in trawls. 



Diet 



From analysis of 195 stomachs, we found that Pacific 

 sandfish were both planktivorous and piscivorous. 

 Percent weight of stomach contents for age-1 Pacific 

 sandfish varied between years (Fig. 4). For both 2001 

 and 2002 combined, decapods, fish, and euphausiids 

 accounted for about 90% of stomach content weight. 

 Fish made up 50% of the weight in 2001, but only 7%. 

 in 2002. The other two heaviest items, decapods and 

 euphausiids, ranged from 30% to 50% and from 17% 

 to 25% of the weight in 2001 and 2002, respectively. 

 Diet of adult Pacific sandfish (2003; 2age-4) consisted 

 of four food items and was dominated by fish and deca- 

 pods (Fig. 4). Fish accounted for 75%c of the weight of 

 stomach contents for 2age-4 fish. Frequency of occur- 



