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Fishery Bulletin 109(3) 
A NC summer 
A NC fall 
O GF summer 
• GF fall 
CM 
o 
Q_ 
CM 
o 
CL 
E 
0 2 
PCI (42% variance) 
A A X fs* 
▲ ▲ A •• 
CM 
O 
CL 
H 
PCI (48% variance) 
-4 -2 0 2 4 
PCI (45% variance) 
Figure 3 
(A-D) Nonmetric multidimensional scaling (MDS) plots of aggregated trawl samples 
averaged by season and station across all years, and coded by region and season. Data 
are square-root transformed fish densities; resemblance based on ranked Bray-Curtis 
similarity. (E-H) Principal components analysis (PCA) plots of seven aggregated envi- 
ronmental variables: chlorophyll-a concentration, water density, water depth, distance 
offshore, photosynthetically available radiation, salinity, and water temperature: log(CHL), 
DEN, log(DEP), sqrt(DIS), sqrt(PAR), SAL, and TMP, respectively, measured immediately 
before or after trawling, averaged by season and station across all years, and coded by 
region and season. Individual variable transformations were applied to improve normal- 
ity; resemblance was based on Euclidian distance. Selected Gulf of the Farallones sta- 
tions are labeled: eastern nearshore (23, 24, 25) and western offshore (FS=Fanny Shoal, 
NFI=North Farallon Island) groups. 
