266 
Fishery Bulletin 1 12(4) 
Table 3 
Total weight (TW)-total length (TL) regression models and TL and TW von Bertalanffy growth models for red 
snapper ( Lutjanus campechanus ) sampled in 2009 and 2010 from recreational catches in 6 regions of the Gulf of 
Mexico: South Texas, North Texas, Louisiana, Alabama, Northwest Florida, and Central Florida. 
Region 
TW-TL model 
TL von Bertalanffy 
growth model 
TW von Bertalanffy 
growth model 
South Texas 
North Texas 
Louisiana 
Alabama 
Northwest Florida 
Central Florida 
7W= 2.49xlO- 8 (rL) 2 - 90 
TW= 7.85xl0- 9 ( TL ) 3 ' 08 
TW= 1.66x10 - 8 (TL) 2 - 97 
TW= 3.61xl0- 8 (T'L) 2 - 85 
TW = 1.20xl0 _8 ( TL) 302 
TW = 5.11xlO _9 (TL) 315 
TL t = 644.5(l-e ( -°- 4189W) ) 
TL t = 908.2(l-e ( ~ 0 1905<wi ) 
TL t = 771.0(l-e ( -°- 2988( ' )) ) 
TL t = 839.8(l-e ( -°- 274TO)) ) 
TL t = 690.2(l-e ( - 03219 «») 
TL,= 760.7(l-e l "°- 3103K,) ) 
TW, = 3.80(l-e ( - 0 - 4185( »>) 2 - 90 
TW,= lO^G-e 1-0 1953 *' 9 ) 308 
TW,= 7.69(l-e ( ~°- 253TO)) ) 2 - 97 
TW,= 12.75(l-e ( -°- 2033!<) >) 2 - 85 
TW, = I8.47(l-e ( -° 1539(i)) ) 302 
TW, = 6.45( l-e ( -°- 3104(O) ) 315 
study from those regions (5%). However, it should be 
noted that our study did not target larger or older fish 
from fishing tournaments as was done in the study 
described in Fischer et al. (2004). The oldest fish col- 
lected in our study (33 years) was approximately 20 
years younger than the oldest specimens (54 and 57 
years) in the GOM reported from previous studies (Wil- 
son and Nieland, 2001; Mitchell et ah, 2004; Allman 
and Fitzhugh, 2007). 
The predominance of small, young fish may reflect 
the recent decline in size at age of red snapper, as well 
as the age truncation of the population due to over- 
fishing (Berkeley et ah, 2004; Allman and Fitzhugh, 
2007; Nieland et al., 2007). The intense overfishing that 
occurred from the mid-1980s to early 1990s resulted 
in the most depleted state of the stock (Cowan et al., 
2011; SEDAR 5 ) and is a plausible reason why a scar- 
Table 4 
Differences between the 2 readers in average percent 
error (APE), coefficient of variation (CV), index of preci- 
sion (D), percentages of agreement (O) for opaque an- 
nuli counts, and percentages of differences in age esti- 
mates (±1, 2, and 3 or more years) in red snapper (Lu- 
tjanus campechanus ) otoliths after the first and second 
readings (n=1808). Red snapper were sampled in 2009 
and 2010 from recreational catches in 6 regions of the 
Gulf of Mexico: South Texas, North Texas, Louisiana, 
Alabama, Northwest Florida, and Central Florida. 
1 st reading 2 nd reading 
APE 
1.77% 
1.08% 
CV 
0.0177 
0.0108 
D 
0.0125 
0.0076 
O 
85.6% 
91.9% 
+ 1 
13.54% 
6.91% 
±2 
0.59% 
1.00% 
±3 or more 
0.18% 
0.18% 
city of older fish was observed in our study (Allman 
and Fitzhugh, 2007; Nieland et al., 2007). Our findings 
are consistent also with recent stock assessments that 
indicate that fish older than 8 years are rarely caught 
in the GOM in the red snapper fisheries (SEDAR 1 ’ 5 ). 
The size- and age-frequency distributions and growth 
models from this study indicate significant demograph- 
ic differences in red snapper across the GOM. Small 
(<550 mm TL), fast-growing fish dominated the recre- 
ational catches of South Texas and the eastern GOM. 
Larger (>600 mm TL), slower-growing fish constituted 
the majority of the catches in the northcentral and 
northwestern regions of the GOM, consistent with the 
findings of Fischer et al. (2004). Also, the larger repre- 
sentation of older fish and the more uniform distribu- 
tion of age classes in the northern and western GOM 
are consistent with previous observations (Mitchell et 
al., 2004; Allman and Fitzhugh, 2007; SEDAR 7 ). The 
dominant age classes (3-6 years) in our study appear 
to have been derived from the strong 2004, 2005, and 
2006 year classes identified in the trawl surveys of the 
recent stock assessments (SEDAR 7 ). These year classes 
may be linked to the recent decline in the GOM shrimp 
fisheries and corresponding reduction in bycatch of ju- 
venile red snapper (Cowan, 2011; SEDAR 7 ). The pres- 
ence of these strong year classes among all 6 regions 
is similar to the consistent GOM-wide year-class pat- 
terns observed by Allman and Fitzhugh (2007). This 
combination of demographic differences and GOM-wide 
year-class consistency supports recent conclusions that 
red snapper form a metapopulation of semi-isolated 
assemblages that are demographically distinct but 
also highly influenced by mixing between assemblages 
(Gold and Saillant, 2007; Patterson, 2007; Saillant et 
al., 2010). 
Our analyses of size at age and von Bertalanffy 
growth models indicate differences in the growth of red 
7 SEDAR (SouthEast Data, Assessment, and Review). 2009. 
Stock assessment of red snapper in the Gulf of Mexico: SE- 
DAR update assessment, 224 p. [Available from http://www. 
sefsc.noaa.gov/sedar/.] 
