Collins et al.: Reproductive patterns, sex ratio, and fecundity of Mycteroperca microlepis 
417 
POFs. Size and age at first spawning, and water 
depth of spawning, were determined with only his- 
tological stage-4 females and stage- 10 males. Depth 
of spawning was indicated by depth of catch, as de- 
termined from interviews with fishermen. 
Batch fecundity estimates involved counting 
whole, hydrated oocytes taken from cross sections 
of gonads and weighed (to the nearest 0.001 g) fol- 
lowing Hunter et al. (1985). Samples were exam- 
ined histologically for the presence of POFs and 
hydrated oocytes. The POFs in samples were noted 
as 0 (absent), 1 (degenerating), or 2 (nondegen- 
erating) (Fitzhugh and Hettler, 1995). Ovaries with 
nondegenerating POFs were omitted from batch 
fecundity estimates to avoid biases in determin- 
ing the number of hydrated oocytes per gram of 
tissue (Hunter et al., 1985). Batch fecundity esti- 
mates were calculated by dividing the product of 
gonad weight and number of hydrated oocytes by 
the sample weight. Any fish collected late in the 
spawning season were omitted from batch fecun- 
dity analyses because of apparent decreases in 
batch size (e.g. Fitzhugh et al., 1988). 
Spawning frequency (the number of spawnings 
per year by a female) was estimated by dividing 
the duration of the spawning season by the aver- 
age number of days between spawning for all fe- 
males (Hunter and Macewicz, 1985; Hunter et al., 
1986). Duration of the spawning season was the 
number of days between the first and last occur- 
rence of hydrated oocytes or POFs each year. The 
average number of days between spawning for all 
females (> or = TL of the smallest hydrated fish) 
was 100% divided by the percentage frequency of 
hydrated females. For example, if the spawning 
season was 100 days long and females spawned 
every two days (with 50% hydrated), then spawn- 
ing frequency would be 50. 
We obtained annual fecundity estimates by multi- 
plying batch fecundity by spawning frequency. Age- 
dependent spawning frequency was estimated with 
stage-4 females within each age group. Because 
spawning frequency varied by age and year, these 
variables were considered separately in calculating 
annual fecundity. We analyzed the following relation- 
ships using regression: batch fecundity (BF) x TL, 
BF x age, and BF x gutted body weight ( GBW=total 
weight — gonad weight = TW - GW); spawning fre- 
quency x age; annual fecundity (AF) x TL, AF x age, 
and AFxGBW. 
Most fish were aged by using whole or sectioned 
sagittal otoliths (Johnson et al., 1993). Whole otoliths 
were adequate for ageing smaller fish (<900 mm TL). 
We sectioned otoliths for larger gag (>899 mm TL) to 
facilitate reading outer rings. 
Figure 1 
Area sampled for gag from commercial and recreational 
catches, 1991-94. Total area sampled, along the 40-80 m 
contour, is encompassed by brackets; most samples were col- 
lected from gag caught in the area south of Panama City to 
the Florida Middle Ground (the latter is indicated by the box). 
Results 
Of all the gag collected from February 1991 through 
December 1994 (rc=2,046), most (61.7%) were taken 
from February through May between Panama City 
and the Florida Middle Ground (Fig. 1). A few 
samples were collected from off Pensacola, St. Pe- 
tersburg, and Ft. Myers, FL. The majority of com- 
mercial and recreational landings were <24 h old 
when sampled. Depth data recorded with samples 
were predominately from commercial catches 
(57.2%). Commercial catches were usually from greater 
water depths (mean=57.2 m, n- 697 ) than those for rec- 
reational catches (mean=32.6 m, n= 73). Most 1991 
samples (n= 463) were from the commercial fishery 
(78.1%). Most 1992 samples (n=318) were from the rec- 
reational fishery (85.5%). Samples in 1993 (z? =617 ) 
came from each of the fisheries in approximately equal 
numbers (commercial =49%). Most 1994 samples 
(n=648) were from the commercial fishery (68.6%). 
Because neither oocyte diameter-frequency distribu- 
tions for oocytes >0.08 mm in diameter (a=0.05; 
Kolmogorov-Smirnov two-sample test; d Q 05 =0.1103; 
