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Fishery Bulletin 112(2-3) 
Figure 1 
Map of locations where Southern Kingfish ( Menticirrhus americanus ) were sampled with hook and line and 
crab pots between April 2008 and May 2009 in the Mississippi Sound, Mississippi, to describe reproductive and 
somatic traits of this species and compare its life history with that of other sciaenids. 
formalin for a minimum of 1 week for histological 
analysis. 
Aging and aging validation of otoliths 
Age estimates were determined from Southern King- 
fish allocated in 10-mm-TL size classes. We randomly 
chose and aged up to 5 specimens per size bin; otoliths 
were processed as described in VanderKooy (2009). 
Otoliths were embedded in a resin block (Buehler 
Epoxicure 4 resin and hardener, Buehler, an ITW Co., 
Lake Bluff, IL) and sectioned at the junction of the 
ostium and sulcus with a saw equipped with a Nor- 
ton diamond wheel (Saint-Gobain, Valley Forge, PA). 
These sections were sanded, mounted on labeled slides 
with clear Crystalbond 509 adhesive (Aremco Products, 
Inc., Valley Cottage, NY), and the slide was cooled and 
dried. The otolith sections were polished with a clear 
Flox-Texx mounting medium (Thermo Fisher Scientific, 
Inc., Waltham, MA). 
Annuli were counted with a Motic BA200 microscope 
(Motic North America, Richmond, Canada) under trans- 
mitted light by 2 independent readers. Fully formed 
annuli were counted to determine the age of the fish 
specimen, and the outer edge margin was coded on the 
basis of the percentage of translucent area beyond the 
final opaque ring (margin codes: 1=0%, 2=33%, 3=66%, 
and 4=99%; [VanderKooy, 2009]). A margin code of 1 
was assumed to signify the month the annulus was 
formed. Numbers of annuli and margin codes were 
compared between readers, and any discrepancies were 
4 Mention of trade names or commercial companies is for iden- 
tification purposes only and does not imply endorsement by 
the National Marine Fisheries Service, NOAA. 
reexamined by a third reader; if agreement could not 
be reached, the otolith was removed from analysis. Mc- 
Dowell and Robillard (2013) validated that Southern 
Kingfish off Georgia produced a single annulus once 
a year. 
Reproductive biology 
Preserved ovaries were dehydrated, embedded in paraf- 
fin, sectioned at 4 pm, and stained with Hematoxylin 2 
and Eosin Y (Thermo Fisher Scientific) for histological 
examination. Slides were assessed microscopically to 
determine ovarian phases defined by Brown-Peterson 
et al. (2011); the 5 reproductive phases of immature, 
developing, spawning capable, regressing, and regen- 
erating, as well as the associated subphases of early 
developing and actively spawning, were recognized. A 
Southern Kingfish was defined as sexually mature once 
it entered the developing phase (DE) and cortical al- 
veoli (CA) oocytes were observed. 
Two quantitative approaches were used to estimate 
the spawning frequency of Southern Kingfish: 1) the 
percentage of fish in the spawning-capable phase with 
or without a 24-h postovulatory follicle (POF) complex 
(hereafter termed the POF method) and 2) the percent- 
age of fish undergoing oocyte maturation (OM) (Hunter 
and Macewicz, 1985) (hereafter termed the OM meth- 
od). Spawning frequency is expressed as the number 
of days between spawning events (see Brown-Peterson 
and Warren [2001] for details). 
Batch fecundity (BF) was estimated for female 
Southern Kingfish in the actively spawning subphase. 
A subsample from the middle of the gonad was re- 
moved, weighed (to the nearest 0.1 g), and preserved 
