216 
Fishery Bulletin 1 10(2) 
14.1 
13.9 
13.7 
13 5 
13.3 
with recruitment 
t 
y=-0.059x+1 31 
r>=0.87 
14 1 
13.9 
13.7 
13.5 
13.3 
with recruitment 
# y=0.159x+13.7 
^=0.62 
i 
13.4 without recruitment 
13.0 
12.6 
i 
12 2 y=-0 124X+262 ^ I " 
r*=0.81 T 
11.8 
Hi 
13.4 
13.0 
12.6 
12.2 # 
* 
11.8 
without recruitment 
13.6 
unknown recruitment 
13.6 
13.4 
13.4 
13.2 
13.2 
13.0 
* 
13.0 
12.8 
y=-0.046x+106 * 
12.8 
12 6 
^=0.45 
12.6 
14 8 
total 
14.8 
14.6 
i 
14.6 
14.4 
Vj. 
’ V*. 
14,4 
14.2 
T 
y=-0.066x+147 • 
14.2 
14.0 
^=0.85 " 
14.0 
2002 2004 2006 2008 2010 
If 
a 
.1 
' • y=0 41x+12.5 
^=0.84 
" y=0.186x+13.0 
r==0.70 
total 
■I 
Year 
• #- " « y=0.209x+14.3 
I -- " r*=0.81 
1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 
PDO 
Figure 6 
Expanded coast-wide biomass indices (natural log of biomass, [ t] ) and standard 
errors as a function of year and annual Pacific Decadal Oscillation (PDO) values 
for 62 dominant demersal taxa collected during the 2003-10 groundfish survey 
subdivided into three subgroups (with, without, and unknown recruitment) 
and summed overall (total). Regression equations for subgroups with signifi- 
cant (P<0.05) or near significant (P<0.10) trends are displayed in the figure. 
Significance levels (P) are listed in Table 2. 
the North Pacific responded to climatic shifts. Major 
changes in coastal ocean productivity of the eastern 
Pacific are correlated with phase changes in the PDO 
and cold eras are associated with enhanced productiv- 
ity. Warm periods are correlated with low productivity 
in the California current system (Brodeur and Ware, 
1992; Hare and Francis, 1995) and the observed de- 
crease in coastwide biomass could reflect the decline in 
biomass during the most recent warm period (2003-06) 
as productivity levels drop. 
Results indicate that not only for individual species 
but also for species grouped taxonomically or by depth 
the change in biomass over time (2003-10) was vari- 
able. For the slope rockfish group (aurora rockfish [Se- 
bastes aurora], bank rockfish [Sebastes rufus], blackgill 
rockfish, darkblotched rockfish, Pacific ocean perch, 
redbanded rockfish, [Sebastes babcocki], rougheye rock- 
fish [Sebastes aleutianus], and splitnose rockfish) and 
the deepwater species group (mean depth >650 m) 
composed of brown cat shark ( Apristurus brunneus), 
