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Fishery Bulletin 107(4) 
f Deca Misc 
Figure 3 
Weight percentages of the major prey 
groups in the stomach samples of three 
rockfish species from the quarterly col- 
lections (April 1998 to September 1999): 
(A) Sebastes flavidus, (B) S. entomelas, 
and (C) S. pinniger. Deca = decapods, 
Eupha =euphausiids, Hetero=heteropods, 
Jelly =jellyfishes, Misc=miscellaneous. 
The PCA ordination scores for the individual stomach 
samples are plotted in the ordination space defined by 
PCA axis 1 and axis 2 (Fig. 5). The ordination scores 
of the seven major prey species groups obtained from 
the transposed PCA analysis are overlaid on the graph. 
The location of each prey species label on the graph 
represents the association of that prey species in relation 
Figure 4 
Weight percentages of the major prey 
groups in the stomach samples from the 
(A) 1998 and (B) 1980 NMFS summer 
survey collections of Sebastes flavidus. 
Amphi=amphipods, Cepha=cephalopods, 
Deca = decapods, Eupha = euphausiids, 
Hetero = heteropods, Jelly = jelly fishes, 
Misc = miscellaneous. 
to the surrounding stomach sample points on the graph 
in terms of its dominance in the diet composition of the 
stomach samples. For example, the stomach sample 
points of S. pinniger in Figure 5 were tightly clustered 
around the middle portion of the rightmost side of the 
graph. When the ordination scores of prey species were 
overlaid, the score for euphausiids was located very near 
the stomach samples of S. pinniger. This result occurs 
because the euphausiid group was the dominant prey 
species group in the diet composition of those stomach 
samples. 
The general linear models for the PCA scores from 
the quarterly fishery samples were highly significant 
(F 16 381 =43.96, P<0.0001, r 2 =0.649 for axis 1; F w 381 = 
30.43, P<0.0001, r 2 = 0.561 for axis 2), and indicated 
that the axis 1 and axis 2 scores were significantly 
related to predator type, season, and their interaction, 
which implies that the food habits differed between 
