118 
Fishery Bulletin 99(1 ) 
Figure 8 
Comparison of mean total fecundity (no POF and mean oocyte diam- 
eter >0.38 mm) at length and the mean fecundity observed in yellowfin 
sole ( Limanda aspera) that had already spawned at least one batch 
(POFs present). 
distribution was not well separated from less 
developed oocytes was lower because oocyte 
recruitment to the advanced stock was not 
complete. We suggest two reasons for this dif- 
ference between the two species. First, the 
discrimination between PY and AY oocytes 
and the criteria used to separate them were 
likely different for the two studies. Exact dis- 
crimination between oocytes that will not de- 
velop and those that are viable cannot occur 
until the distributions are completely sepa- 
rate. Second, rates of oocyte atresia between 
the two species may be different. Higher rates 
of PY and AY atresia may account for a de- 
crease in fecundity as the AY distribution ad- 
vances. As Hunter et al. (1992) noted, the fate 
of PY oocytes is uncertain; perhaps some in- 
dividuals retain them for an additional series 
of batch spawnings. 
Although multiple groups of oocytes are not 
continuously developed as are those observed 
for indeterminate fishes, such as the northern 
anchovy, Engraulis mordax (Hunter and Le- 
ong, 1981), yellowfin sole appear to have the 
potential to recover spent ovaries and spawn 
another series of batches. Remnants of chori- 
ons from hydrated oocytes in the lumen of ova- 
ries containing a unimodal stock of advancing 
yolked oocytes with diameters significantly less 
than those of spawning fish (Fig. 4) suggest that 
at least some individuals can produce more than 
one series of batches in a single year. Annual fe- 
cundity for each of these individuals would be 
significantly greater than the estimated total fe- 
cundity. Although yellowfin sole exhibit a deter- 
minate group-synchronous mode of oocyte devel- 
opment, some individuals may spawn more than 
one series of batches; therefore, annual fecundity 
must be considered indeterminate. 
Comparison of total fecundity between 
southeast and northwest areas 
Total fecundity for yellowfin sole was com- 
pared for the northwest and southeast areas 
of the eastern Bering Sea. Although Nichol 
(1997) found that yellowfin sole growth and 
size at maturity were greater in the northeast 
area of the eastern Bering Sea compared with 
the southeast area (Fig. 1), we found no dif- 
ferences in fecundity between areas. Neither 
slopes (ANCOVA: F=0.09; P=0.77; df =1, 144) 
nor intercepts (ANCOVA: F=0.56; P>0.10; df 
= 1, 145) were different for the log-transformed (linear) 
length-fecundity relationships. 
Comparison of results with those from other authors 
With the exception of fecundity data presented by Fadeev 
(1970), the relationship between yellowfin sole fecundity 
and fish length appears similar between east and west 
sides of the Bering Sea and among years (Fig. 9). Ivankov 
and Ivankova (1974), who reported that yellowfin sole in 
the northwestern Sea of Japan spawn up to five batches, 
presented slightly lower values of total fecundity com- 
pared with our results. Tikhonov (1977) presented sim- 
ilar length-fecundity relationships for yellowfin sole off 
