Powers et a!.: Age composition and distribution of Sciaenops ocellatus in offshore waters of the north central Gulf of Mexico 
291 
(e.g., Dixie Bar, AL). Less than 25% of anglers reported 
fishing in waters greater than 3 miles offshore near 
artificial reefs. The majority (60%) of our bottom long- 
line sampling effort occurred in state waters with the 
remaining 40% in federal waters. The vast majority of 
our catch occurred within 3 miles from shore and was 
highest near the inlets. Given that the spatial distribu- 
tion of effort between the fishery-dependent and inde- 
pendent collections overlaps, differences between size 
and age frequency between the fishery-dependent and 
independent collections are likely due to the broader 
selectivity of the recreational (hook and line) gear than 
to the standardized hook size and bait type in our bot- 
tom longline survey. The bottom longline selected for 
fish age 6 and above (>800 mm), whereas 50% of the 
hook and line catch was 2-5 year-old fish and did not 
provide large sample sizes of older age classes. The 
bottom longline tended to capture older age classes of 
red drum and their abundance is a key determinant for 
stock condition for long-lived fish. 
Central to the current management scheme for red 
drum is protection of the spawning population. A post- 
moratorium increase in adult red drum is apparent 
from examination of the year-class frequency in our 
data; however, the large increase after the moratorium 
declined to more modest levels in the last ten years dur- 
ing which fish could be considered fully selected for the 
longline gear (1996-2006). This trend corresponds to 
the overall landings pattern for the GOM. Peak, and ap- 
parently unsustainable, commercial landings occurred 
in 1986 around 6.3 million kg. After the moratorium, 
total landings decreased to 1.5 million kg annually but 
have steadily increased and recreational landings were 
approximately 6.3 million kg in 2010. Currently, Loui- 
siana, Mississippi, and Alabama allow retention of one 
red drum above the catch limit per day, whereas Texas 
allows two oversized red drum per year. Data collected 
from the ADSFR suggest 2-5 year-old fish are readily 
available to recreational anglers and the recreational 
fishery could be a significant source of mortality for 
the spawning stock. Although our data represent a 
limited geographic range of the stock, the data indicate 
the need to re-assess the current management scheme 
and evaluate the bag limits and escapement rates of 
red drum. 
Conclusions 
Assessment of stock conditions for fish populations 
under severe harvest restrictions is complicated by a 
lack of fishery-dependent data. Fishery-independent 
surveys could be used to fill this void; however, funds 
for fishery-independent surveys targeting nonexploited 
stocks are limited. Key to monitoring these stocks will 
be increasing the efficiency of data collection ( sensu 
Link et al., 2008). Stock assessments of red drum are 
complicated by the mosaic of differing state regulations 
and the harvest ban in federal waters. Commercial 
catch from the GOM red drum fishery is minimal (Mis- 
sissippi allows a limited harvest) and recreational size 
limits vary between states. Given these differing spatial 
management schemes, fishery-independent sampling is 
critical for establishing long-term abundance indices 
and determining age composition across the GOM for 
effective monitoring. Our results suggest that bottom 
longline surveys could fill this role. Specifically, designs 
should be optimized by focusing in coastal waters <20 m 
deep, where 99% of our red drum catch occurs. Targeting 
effort in the spring (March-April) and fall (October- 
November) would be expected to maximize the sample 
size for age determination. Although annual bottom 
longline surveys are currently conducted by the National 
Marine Fisheries Service ( see Driggers et al., 2008) and 
provide fishery-independent data for sharks and red 
snapper, effort is limited in <20 m depth and the survey 
occurs only from July through September. Expanding 
already existing fishery-independent surveys is likely 
the most cost-effective method of examining stocks that 
have limited fishery-dependent data. 
Acknowledgments 
We thank the technicians at the Fisheries Ecology 
Laboratory who collected all the fisheries-independent 
data. We especially thank those postdoctoral research- 
ers, graduate students, technicians, and interns who 
collected and processed fish. M. Kenworthy and M. 
Valentine assisted with the processing and aging of red 
drum otoliths for this study and M. Ajemian assisted 
with aerial flight analysis and index construction. We 
would like to thank E.J. Dick for providing R code for 
index calculation. The authors are grateful to vessel 
captains R. Collier, T. Guoba, C. Lollar, and R. Wilson 
affiliated with the Dauphin Island Sea Lab. We also 
acknowledge the assistance of the Mobile Jaycees in 
creating the red drum jackpot category that facili- 
tated fishery-dependent collection of red drum. This 
study was funded by the MARFIN program of the 
National Marine Fisheries Service (award number 
NA08NMF4330405). 
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