Saari et al.: Regional differences in the age and growth of Lut/anus campechanus in the Gulf of Mexico 
271 
tion across a long period of time (Trippel et al., 1997; 
Berkeley et al., 2004; Palumbi, 2004; Kulaw, 2012). 
Conclusions 
This study documented the highly truncated age struc- 
ture of the recreational catches of red snapper and 
highlighted the demographic differences in size, age, 
and growth of this species across the GOM. The poten- 
tial mechanisms in the observed demographic variation 
include environmental differences, fishing pressure, 
habitat preference, and management regimes; however, 
no definitive conclusion about cause and effect can be 
made. Implications of these differences along with the 
theory that red snapper form a metapopulation in the 
GOM should be considered in future stock assessments 
and management decisions. 
The most recent stock assessment indicates that red 
snapper in the western GOM are beginning to recover 
from overfishing (SEDAR 5 ). However, we documented 
on the basis of recreational catches across the GOM 
that red snapper continue to exhibit a severely trun- 
cated age structure. It is expected that as the stock 
rebuilds, there will be a shift to an older age structure 
(Allman and Fitzhugh, 2007; SEDAR 5 ). An increase in 
red snapper biomass has been observed in the fisher- 
ies; however, an age shift was not readily apparent in 
our study, the latest stock assessments, or other recent 
studies (Allman and Fitzhugh, 2007; SEDAR 5 ). Iden- 
tification and protection of the strong year classes of 
2004-06 will allow for stock recovery and help elimi- 
nate the truncated age structure as more fish reach 
maximum spawning potential (Berkeley et ah, 2004; 
Palumbi, 2004). 
Acknowledgments 
Funding for this research was provided by the U.S. 
Department of Commerce Marine Fisheries Initiative 
(MARFIN grant NA08NMF4330409). We appreciate the 
field support from M. Sluis, G. Harwell, E. Roche, and 
many others. We offer our gratitude to A. Fischer for 
training our otolith readers and D. Kulaw for assis- 
tance in sampling and counting annuli. We also thank 
the numerous fishermen who allowed us to sample 
their catches. Finally, we would like to thank K. Simon- 
sen and several anonymous reviewers for constructive 
reviews of this article. 
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