Friess and Sedberry: Age, growth, and spawning season for Beryx decadactylus 
29 
A 
8 0 0 3 3 10 20 20 16 3 2 12 
J FMAMJ J ASOND 
Month 
□ Developing 
DIE POFs present 
■ Ripe 
□ Spent 
H Resting 
Figure 7 
Percentages of reproductive stages observed for (A) female 
(rc = 97) and ( B ) male (n = 56) red bream ( Beryx decadactylus) 
collected from the commercial fishery operating around the 
Charleston Bump from 2003 to 2008. Sample sizes for each 
month are indicated above the bars. POF = postovulatory 
follicle. 
limited to young, fast-growing fish and can lead to se- 
rious aging error if used incorrectly (Campana, 2001). 
Beamish (1979) showed that ages determined from the 
surface of otoliths tend to underestimate true ages 
when compared to age estimates derived from trans- 
verse sections, and there are several examples in the 
literature of deep-sea fishes for which ages have been 
severely underestimated by whole otolith analysis in 
the past. Orange roughy (Hoplostethus atlanticus) for 
example, was once thought to live up to 20 years, but a 
centenarian life span has since been validated for this 
species through lead-radium dating (Andrews et ah, 
2009). Bennett et al. (1982), also using lead-radium 
dating, showed that ages estimated from sectioned 
otoliths greatly exceeded those from whole otoliths for 
the rockfish genus Sebastes. 
Although underaging of older fish was likely a factor 
contributing to the discrepancy in longevity estimates 
reported here, there was little overlap in observed 
fish lengths between this and previous studies, which 
limits our ability to make direct comparisons. Seventy- 
three percent of the fish sampled in this study had 
fork lengths of 500 mm or more, and none measured 
less than 410 mm FL. Conversely, fish from the Azores 
aged by Isidro (1996) were as small as 200 mm FL, 
but none reached 500 mm FL (Isidro, 1996). It is be- 
yond the scope of this article to fully investigate the 
reason for this pattern in size differences, but evidence 
indicates that sampling bias may not be the primary 
explanation. In a recent study published by Menezes et 
al. (2009) sampling was undertaken at seamounts in 
the eastern North Atlantic with longlines at depths of 
up to 2000 m, but red bream were caught at a similar 
depth range to that in which the Charleston Bump 
fishery operates, roughly 450-600 m. The largest red 
bream caught in the study by Menezes measured 47 
cm, which is still much less than the average length 
reported in our study. The observed size difference 
on opposite sides of the North Atlantic could thus be 
indicative of a true difference in population age and 
size structure. 
The parameters of the red bream VBGF reported 
here for the combined sexes vary slightly from those 
reported by Isidro (1996) for the Azores. Isidro’s of 
56 cm is 20 cm less than what was found in this study, 
a reflection of the smaller sizes of specimens observed 
in the eastern North Atlantic. Isidro estimated a k 
of 0.107/yr, which is slightly higher than the 0.094/ 
yr reported here. In addition, the t 0 of -3.69 reported 
here is more negative than the -2.83 years reported 
