Table 2 — Average number of parasites in designated area of parasitized fillet 



For delineation of area, see Figure 1. 



Table 3 — Incidence of parasitisation in Pacific ocean perch and incidence 

 of two or fewer parasites among the parasitized fish 



Fishing 

 Ground 



Incidence of 

 oarasitization in 

 ell of the fish 



Incidence of two or fewer 

 parasites in the parasitized 

 fish 



Northern 



Middle 



Southern 



Percent 



5U 

 67 

 82 



fillet (as compared with more than 30 

 per fillet in fish from the northern 

 area). In these fish, most of the para- 

 sites occurred in the meaty ' 'shoulder" 

 portion of the fillet, but the tail portion 

 also was commonly parasitized. 



The incidence of parasitization in 

 miscellaneous rockfish from the middle 

 area was as high as that in Pacific 

 ocean perch from the northern area 

 (approximately 40 percent). This ob- 

 servation is in accordance with the 

 belief in the industry that other rock- 

 fish are more generally parasitized 

 than are Pacific ocean perch. Less 

 than half the parasitized fillets showed 



one or two parasites per fillet, but 

 nearly three-quarters had three or 

 less. The highest infestation observed 

 was 13 parasites per fillet. The tail 

 portion of the fillet was most inten- 

 sively parasitized, but parasites oc- 

 curred generally throughout the fillet. 



The incidence of parasites inS. pinniger 

 from the middle area, however, was 

 very low. This observation accords 

 well with the finding for fish of this 

 species caught in northern waters. All 

 infested fillets had one or two parasites 

 per fillet. In the few fish that were in- 

 fested, the parasites occurred mainly 

 in the anterior dorsal region of the 



