617 
Abstract— Age and growth were exam- 
ined of red snapper, Lutjan us campecha- 
nus, captured in an extensive (3100 
km 2 ) artificial reef area off Alabama in 
the northern Gulf of Mexico. Sagittal 
otoliths were removed from individu- 
als (n=1755) sampled from recreational 
catches and tournament landings. Mar- 
ginal increment analysis of sectioned 
otoliths revealed that a single opaque 
zone formed annually in sagittae from 
January through May. Fish ages were 
estimated from the number of opaque 
zones in otoliths, timing of opaque 
zone formation, sampling date, and a 
presumed birthdate of 1 July. Esti- 
mated growth of recaptured red snap- 
per (n=288) from a tagging experiment 
was similar to growth estimated from 
otolith-aged fish and corroborated oto- 
lith aging methods. The von Bertalanffy 
growth function fitted to length-at-age 
data was TL = 969 mm ( l-e -0192 *' -0020 *) 
(P<0.001; r 2 =0.99), which was similar 
to reported growth functions for west- 
ern Gulf of Mexico and Atlantic red 
snapper. Results of our study are con- 
sistent with the single stock hypothesis 
for Gulf of Mexico red snapper. 
Manuscript accepted 15 March 2001. 
Fish. Bull. 99:617-627 (2001). 
Age and growth of red snapper, 
Lutjanus campechanus, 
from an artificial reef area off 
Alabama in the northern Gulf of Mexico 
William F. Patterson III 
Coastal Fisheries Institute 
204 Wetlands Resources Building 
Louisiana State University 
Baton Rouge, Louisiana 70803 
E-mail address: wpatte2@LSU.edu 
James H. Cowan Jr 
Department of Marine Sciences 
University of South Alabama 
Mobile, Alabama 36688 
Charles A. Wilson 
Department of Oceanography and Coastal Studies 
Louisiana State University 
Baton Rouge, Louisiana 70803-7503 
Robert L. Shipp 
Department of Marine Sciences 
University of South Alabama 
Mobile, Alabama 36688, 
Red snapper, Lutjanus campechanus, 
are large, predatory reef fish belonging 
to the family Lutjanidae. They gen- 
erally are found from Cape Hatteras, 
North Carolina, to the Yucatan Penin- 
sula, including the waters of the Gulf 
of Mexico (GOM) but not the Caribbean 
Sea (Hoese and Moore, 1998). Through- 
out their range red snapper are dis- 
tributed along the continental shelf out 
to the shelf’s edge and demonstrate 
affinity for vertical structure. Adults 
aggregate on or near coral reefs, gravel 
bottoms, or rock outcrops, as well as 
on artificial reefs, oil rigs, and wrecks 
(Moseley, 1966; Szedlmayer and Shipp, 
1994; Stanley and Wilson, 1997). 
Red snapper support economically 
valuable recreational and commercial 
fisheries in U.S. waters of the GOM 
(GMFMC, 1989). Federal management 
of GOM red snapper is based on the as- 
sumption that fish from Florida to Tex- 
as constitute a single stock. Although 
genetic evidence supports this assump- 
tion (Camper et al., 1993; Gold et ah, 
1997 ; Heist and Gold, 2000 ), fish are not 
distributed uniformly across the north- 
ern GOM. Fisheries-dependent data 
suggest there is a center of red snapper 
abundance off southwest Louisiana and 
a second, smaller center of abundance 
off Alabama (Goodyear, 1995a; Schir- 
ripa and Legault, 1999). For example, 
from 1981 to 1998 estimated Louisiana 
landings of red snapper (commercial 
and recreational catch from state and 
federal waters) accounted for 32.6% 
(mean) ±1.5% (SE) of the total GOM 
harvest, whereas Alabama landings ac- 
counted for 11.4% ±0.9% of the total 
catch (Schirripa and Legault, 1999). 
Although fewer red snapper are har- 
vested from waters off Alabama than 
from the northwestern GOM, the red 
snapper fishery off Alabama is unique 
in several ways. Given that Alabama’s 
GOM coastline represents only about 
3.0% of the coastline from Tampa, Flor- 
ida, to Brownsville, Texas, a dispropor- 
tionately high percentage of the GOM 
red snapper harvest is caught and land- 
