Rodgveller et al . : Age at maturity, skipped spawning, and fecundity of female Anoplopoma fimbria 
101 
47) (sablefish maximum age is reported to be 94 years 
[Kimura et ai. 1998]); data from older fisb are needed 
to further test this model assumption. 
Although the relative reproductive output did not in- 
crease with age, mature oocyte size did. Mature oocyte 
size could have increased with age because older fe- 
males have more energy reserves for reproduction than 
have younger females. These energy reserves could be 
contributed to development of oocytes, and more energy 
put to that end would result in larger oocytes. If larger 
eggs in sablefish increase larval fitness, older females 
(>12 years, the age at which almost 100% of fish are 
mature) may contribute more to the population than 
do younger females. For example, an increase in energy 
reserves and survival of larval black rockfish ( Sebastes 
melanops ) has been observed for offspring from older, 
larger females (Berkley et al., 2004). Alternatively, 
older females may initiate oocyte development earlier 
than younger sablefish and, therefore, have larger oo- 
cytes. Earlier development may also indicate an ear- 
lier spawning date for older females, as has been seen 
in other marine fish species (Stark, 2007; Wright and 
Trippel, 2009; Rodgveller et al., 2012). Mason’s (1984) 
study of sablefish fecundity indirectly supports the hy- 
pothesis that older females spawn earlier than younger 
females. A decrease in relative fecundity with length 
could have been caused by an earlier spawning time 
of larger females. If larger females initiated matura- 
tion earlier than smaller females and had spawned at 
least 1 batch of eggs, the result would be a decrease in 
relative fecundity with length. Mason may have missed 
evidence of batch spawning in larger fish because there 
was no microscopic examination for classification of 
ovaries in that study. 
Acknowledgments 
We thank Captain B. Ashley and the crew of the char- 
tered FV Gold Rush. We also thank our coworkers at 
NOAA’s AFSC: S. Kotwicki; C. Conrath for logistics; 
D. Anderl for aging otoliths; G. Fleischer and R Rigby 
for assistance with the vessel charter; and P. Rigby, J. 
Heifetz, and D. Hanselman for helpful reviews. 
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