186 
Fishery Bulletin 112(2-3) 
100 150 200 250 300 350 
TL (mm) 
Figure 4 
Plot of percentage of female Southern Kingfish (Menticirrhus 
americanus) collected from the Mississippi Sound, Mississippi, be- 
tween April 2008 and May 2009 that reached maturity (entered 
the reproductive cycle) in relation to total length (TL) by 10-mm- 
TL size bins. The vertical line at 171 mm TL indicates the TL 
where 50% of individuals were mature (TL 50 ). 
(i? 2 =0.164, Fi g = 1.77, P=0.216). The 11 specimens used 
in the fecundity calculations were collected in May, 
July, August, and September, and the highest mean 
BF occurred in August at 38,722 eggs (SE 20,288) and 
the lowest mean BF, in September at 33,730 eggs (SE 
12,544). There were only 2 age classes represented in 
the fecundity analysis: age-1 (n- 4) and age-2 (n= 7) fish 
(Table 5). Mean BF was slightly higher in age-2 fish 
at 36,622 eggs (SE 6122) than in age-1 fish at 33,730 
eggs (SE 15,591); however, there was no significant re- 
lationship between logqo BF and logio age (P 2 =0.015, 
F h 9=0.136, P=0. 721). 
Relative batch fecundity had a range of 94.4-509.5 
eggs g _1 OFBW and a mean of 213.1 eggs g _1 OFBW 
(SE 35.7) (Table 5). Like the BF results, results for 
RBF had its highest mean in August at 259.6 eggs g _1 
OFBW (SE 124.9) and lowest mean in September at 
168.1 eggs g' 1 OFBW (SE 70.3). Unlike the BF results, 
results for mean RBF were lower in age-2 fish, with 
200.2 eggs g _1 OFBW (SE 29.4), than in age-1 fish, with 
235.7 eggs g _1 OFBW (SE 91.5). Potential annual fe- 
cundity for Southern Kingfish in the northcentral GOM 
indicates that a female with a somatic wet weight of 
176 g could potentially spawn 924,846 eggs over the 
course of the spawning season. 
Sciaenidae life-history traits: a comparative analysis 
Wide variation was observed in the somatic and repro- 
ductive traits examined for the 21 sciaenid populations 
that were analyzed in this study (Appendix table). For 
instance, Silver Seatrout ( Cynoscion nothus), a GOM 
species, has the lowest reported maximum age (1.5 
years) of the 21 species, but Black Drum 
( Pogonias cromis), another GOM species, 
has the oldest reported maximum age (43 
years). Duration of spawning season ranged 
from 2 months (Black Drum) to 7-10 months 
for White Croaker ( Genyonemus lineatus), a 
Pacific species. Size at maturity varied from 
110-120 mm TL in Silver Perch ( Bairdiella 
chrysoura ), a GOM species, to 900 mm TL for 
Atlantic populations of the Red Drum ( Sci - 
aenops ocellatus). Life-history traits least 
frequently reported for sciaenid species in- 
clude RBF and spawning frequency (Appen- 
dix table). Of the 11 species or populations 
with available spawning-frequency data, 
Queenfish ( Seriphus politus ) has the longest 
interspawning interval of 7.4 days and Sil- 
ver Perch has the shortest interval of 1.3-1. 6 
days. 
The PCA of the 5 somatic and reproductive 
traits produced 2 meaningful components 
that accounted for 68.1% of the total varia- 
tion of the original data set. The first prin- 
cipal component (PC 1) accounted for 43.1%, 
whereas the second principal component (PC 
2) accounted for 25.0%. Maximum TL and age 
at maturity both positively loaded on PC 1, but RBF 
loaded negatively on PC 1 (Table 6). In contrast, dura- 
tion of spawning season and parameter b loaded posi- 
tively on PC 2 (Table 6). We interpret PC 1 as a size- 
related component of life history, and PC 2 represents 
spawning season dynamics. Overall, the PCA indicated 
3 general trends in sciaenid life history: 1) fishes that 
reach a larger maximum TL and older age at maturity 
tend to have lower RBF, 2) a higher RBF is associated 
with a shorter spawning-season duration, and 3) a lon- 
ger spawning-season duration is associated with fishes 
that have higher b values. 
Five groups of sciaenid populations can be discerned 
in the PCA biplot (Fig. 7). Group A, consisting of fishes 
with high maximum TL, greater age at maturity, and 
low RBF, is composed of GOM species Red Drum and 
Black Drum. Group B consists of fishes with longer 
spawning seasons, greater b values, low RBF, smaller 
maximum TL, and lower age at maturity and is repre- 
sented by Sand Seatrout (Cynoscion arenarius ), South- 
ern Kingfish, White Croaker, and Queenfish, a mixture 
of species from all 3 regions, the GOM as well as the 
Atlantic and Pacific. Group C, made up of fishes with 
higher RBF, shorter spawning season, young age at 
maturity, small maximum TL, and low b values, is rep- 
resented by 2 GOM species: Spot (Leiostomus xanthur- 
us) and Silver Perch. Group D consists of fishes with 
more intermediate traits, such as small maximum TL, 
low age at maturity, and moderate spawning season, b 
values, and RBF. A species each from the Atlantic and 
GOM represent group D: Atlantic Croaker ( Micropogo - 
nias undulatus) and Silver Seatrout. Finally, group E 
also is an intermediate group with characteristics of 
