Nichol and Acuna: Annual and batch fecundity of Limanda aspera in the eastern Bering Sea 
115 
n= 11 
Code 2, Residual - I • — 
chorion material present 
Code 2-3, POF - 
(jj (partially spawned) 
a. 
& 
jk Code 3, no POF - 
ro (HYs = first batch) 
O 
Code 2, MNs, no POF - 
n = 46 
n = 24 
I • 1 
n = 45 
I — • — I 
Code 2, no MNs, no POF - 
n = 99 
' 1 > 1 — ' 1 ■ 1 > 1 ■ 1 ■ 1 
0 32 0 34 0 36 0 38 0 40 0 42 0 44 0 46 
Mean oocyte diameter (mm) 
Figure 4 
Comparison of mean yolked oocyte diameters among ovaries at different levels of devel- 
opment, from maturing (maturity-code 2) ovaries with no migratory nucleus stage (MN) 
oocytes (>0.38 mm) to maturity-code 3 ovaries with postovulatory follicles (POFs) pres- 
ent. Error bars indicate 95% confidence intervals. See Table 1 for description of ovary 
maturity codes. 
Table 4 
Occurrence of alpha (a) atretic oocytes among advanced vitellogenic (AY through HY) and partially-yolked (PY) oocytes within yel- 
lowfin sole ( Limanda aspera ) ovaries (n=75 females). AY = advanced-yolked; HY = unovulated hydrated. 
Maturity 
code 
No. of 
females 
sampled 
No. of 
females with 
a-atretic AY- 
HY oocytes 
Proportion of 
a-atretic among 
all AY-HY 
(min. -max.) 
No. of 
females 
with PY 
oocytes 
No. of 
females with 
a-atretic PY 
oocytes 
Code 2, no POFs (prespawning) 
28 
2 
0.01-0.025 
24 
3 
Code 3, no POFs (first batch) 
13 
5 
0.004-0.058 
4 
3 
Codes 2 and 3, POFs present (partially spawned) 
23 
6 
0.005-0.037 
6 
3 
Code 2, residual chorion tissue present 
11 
2 
0.061-0.134 
9 
2 
Total fecundity 
In choosing ovaries to be used to estimate total fecundity, 
we selected ovaries that were advanced enough that the 
advancing stock (AY to MN) could be discriminated from 
less advanced oocytes (PY), yet were not advanced enough 
for there to have been potential spawning. First, we elimi- 
nated ovaries with mean oocyte diameters <0.38 mm due to 
the overlap in AY and PY distributions. Secondly, we elimi- 
nated ovaries with mean oocyte diameters greater than 0.44 
mm (n= 20) in an attempt to eliminate partially spawned 
ovaries that could not be identified with histological eval- 
uation; POFs were not found in these ovaries; however, 
because the level of oocyte advancement (mean AY diam- 
eter) was similar to ovaries that did contain POFs (Fig. 4), 
the occurrence of recent batch spawning was possible. 
Inclusion of ovaries with mean AY-oocyte diameters 
<0.38 mm as well as those >0.44 nun can potentially bias 
estimates of total fecundity. Estimates of total fecundity, 
measured from fish where distributions of PY and AY 
oocytes overlapped (Fig. 3), were higher than estimates 
from ovaries with more advanced oocytes (Fig. 5; Table 
5). We compared yellowfin sole length-fecundity relation- 
ships of fish with ovaries that had mean AY-oocyte diam- 
eters >0.38 mm and <0.44 (n = 148) to those with mean 
diameters <0.38 mm (n=80). Linear comparisons of the 
\og(Iength)-\og(fecundity ) relationships between the two 
data sets indicated similar slopes (F=0.08; P= 0.7725; df=l, 
