Nichol and Acuna: Annual and batch fecundity of Limanda aspera in the eastern Bering Sea 
117 
Table 6 
Linear regression results from the model logtF) = log(a) + b\og(L) + log(c); the log-transformation of model F = aL h c, where F = total 
fecundity, L = fish length (cm), and a, b, c are coefficients. Coefficient c represents the interaction of mean oocyte diameter on F. A 
series of regressions were run, first by using all data where the mean yolked oocyte diameter was >0.38, then with data sets that 
excluded ovaries with high mean oocyte diameters (i.e. ovaries with mean oocyte diameters >0.46 mm, >0.45 mm, >0.44 mm). 
Mean oocyte diameter 
range of ovaries 
used in analysis 
Estimate 
P-value of 
H 0 : log(c) = 0 
Log(a) 
b 
Log(c) 
n 
> 0.38 mm 
6.40 
3.43 
-1.22 
0.003 
168 
0.38-0.46 mm 
6.35 
3.44 
-1.22 
0.006 
165 
0.38-0.45 mm 
5.84 
3.42 
-1.06 
0.026 
160 
0.38-0.44 mm 7 
3.07 
3.44 
-0.33 
0.525 
148 
1 This data set, which excluded 
ovaries with mean 
oocyte diameters > 0.44 
mm, indicated no significant effect of 
mean oocyte diameter 
on the estimate 
of total fecundity. 
where B = batch fecundity; and 
TL = total fish length in centimeters 
(Table 5). 
Number of batches 
The number of batches that a female of a given 
length spawns was estimated as F/B (above). 
Yellowfin sole are estimated to spawn an aver- 
age of 8 to 11 batches prior to the spent ovary 
condition. The frequency of batches appears to 
be slightly higher for larger fish. 
Discussion 
Determinate or indeterminate fecundity? 
Fish with determinate fecundity are defined as 
those with ovaries whose advancing stock of 
oocytes represent the entire number of eggs to 
be spawned that year (Hunter et ah, 1989; Hor- 
wood and Walker, 1990; Hunter et al., 1992). 
Fish with indeterminate fecundity, in contrast, 
are defined as those whose ovaries continu- 
ously mature yolked oocytes from unyolked 
oocytes; thus the “standing stock” of advanced 
oocytes does not represent the total number of eggs to 
be spawned that year (Hunter et ah, 1989). Oocyte size 
frequencies of various stage oocytes (i.e. advanced-yolked, 
partially yolked, unyolked) have been used as criteria to 
determine if a fish has determinate fecundity (Hunter 
et ah, 1989; Hunter et ah, 1992; Horwood and Walker, 
1990). If a break or “hiatus” has occurred between the 
advanced-yolked distribution and the less advanced ones, 
then the advanced-yolked distribution could be considered 
the determinate stock. This break in oocyte distributions 
was observed for yellowfin sole, and it is clear that batches 
are spawned from the advanced-yolked mode. A deter- 
minate mode of oocyte development in yellowfin sole is 
further indicated by the fact that total fecundity was sub- 
stantially lower in fish that had spawned at least one 
batch (Fig. 8) — an indication that there is no oocyte recruit- 
ment to the advanced oocyte stock once spawning begins. 
Hence, although yellowfin sole spawns eggs intermittently 
in batches, they undergo a group synchronous mode of 
oocyte development. 
In contrast to other fish with determinate fecundity, yel- 
lowfin sole fecundity estimates were higher among indi- 
viduals with less-developed ovaries where PY and AY oo- 
cyte distributions overlapped (Fig. 5). Hunter et al. ( 1992) 
indicated the opposite for Dover sole; they found that fe- 
cundity among individuals where the advanced-stock size 
