Echave et a!.: Interdecadal change in growth of Anoplopoma fimbria in the northeast Pacific Ocean 
369 
Southeast Kodiak 
Shumagin 
Chirikof 
Bering 
Aleutian 
so 
70 
60 
50 
40 
VB model fitted to 1981-83 
bias-corrected data, r >= 515 
VB model fitted to 1 996-2004 
bias-corrected data, n=4899 
10 15 
20 
25 30 
Age 
Figure 4 
Comparison by management region of female sablefish (Anoplopoma fimbria) 
von Bertalanffy (VB) growth curves fitted to bias-corrected age-length data 
from the period 1981-93 (shown as a dotted line) and fitted to age-length data 
from the period 1996-2004 (shown as solid line). Sample sizes ( n ) contributing 
to the VB analysis are listed in Table 2. 
Table 6 
Comparison of 2 age-weight models used for analyses of regional effects on growth of female sablefish (Anoplopoma fimbria) in 
Alaska. The most reasonable model, indicated with an asterisk (*) is the reduced model with a residual sum of squares (RSS) not 
significantly greater than the RSS for the full model. rc=the number of observations, and / 2 =the chi-squared value. 
Model 
RSS 
X 2 
P 
No. of parameters 
n 
Data split into 6 regions * 
262 
24 
All data pooled 
277 
145.5 
<0.001 
4 
3493 
Male sablefish in all of the 6 regions displayed highly 
significant differences in weight-at-age, although their 
growth curves appeared similar. These minor growth 
differences may not be of biological importance and 
may not need to be considered for assessment purposes. 
Biological and oceanographic explanations 
for observed changes 
There was no evidence of a common climatic forcing 
factor among the management regions in relation to 
