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Fishery Bulletin 99(4) 
Figure 5 
Cross section of sagittal otolith from the oldest red snapper, Lutjanus campechanus, from among 
3791 specimens sampled from the recreational and commercial fisheries of the Gulf of Mexico off 
Louisiana from 1989 to 1992 and from 1995 to 1998. Abbreviations are Do = dorsal, V = ventral, 
SA = sulcus acousticus, Di = distal, and Pr = proximal. Arrows with numbers indicate positions of 
opaque annuli and their enumeration. 
the dominance of ages 2-5 may reflect the practices of the 
fishermen who target red snapper and a migratory aspect 
of the species’ life history. Age-0, and to a lesser extent 
age-1, red snapper are known to inhabit shallow water 
areas devoid of complex habitats or vertical relief where 
some are vulnerable to capture in trawls. This behavior 
is illustrated in fishery-independent trawl data from the 
GOM, specifically the Fall Groundfish Survey and the 
Summer SEAMAP Survey, in which the great majority of 
red snapper captured are age 0 and 1 (Schirripa and Le- 
gault 2 ). It has been hypothesized that the disappearance of 
red snapper from the trawl data at age 1 represents their 
migration to structures such as oil and gas platforms that 
presumably provide refuge from large predators (Render, 
1995). It is during this residence at the numerous oil and 
gas platforms off Louisiana that red snapper become vul- 
nerable to fishing gear. Because the platforms are easily 
located and potentially harbor large populations of red 
snapper and other fish species (Stanley and Wilson, 1996, 
1998), they are the preferred destinations for both com- 
mercial and recreational fishermen. The very low numbers 
of individuals of age >6 in our sample population likely re- 
sult from both removal from the population through fish- 
ing and natural mortalities and emigration away from the 
oil and gas platforms to alternative habitats where they 
are less susceptible to capture. 
It is difficult to compare the maximum observed red 
snapper longevity reported in our study with those re- 
ported in earlier studies (Moseley, 1966; Futch and Bru- 
ger, 1976; Wade, 1981; Nelson and Manooch, 1982; Render, 
1995; Szedlmayer and Shipp, 1994; Patterson, 1999) be- 
cause of the assortment of aging techniques (scales, whole 
or sectioned otoliths, length frequencies) and the variety of 
sources (commercial, recreational, or both) used. All show 
a predominance of relatively young individuals (< 10 yr). 
Flowever, recent advances and refinements in otolith prep- 
aration technology have allowed red snapper to be aged 
reliably up to the following ages: 42 yr (Szedlmayer and 
Shipp, 1994), 53 yr (Render, 1995), 31 yr (Patterson, 1999), 
and 52 yr (our study). Despite the sparsity of old red snap- 
per among these research efforts, there can be little doubt 
that red snapper at least have the potential to achieve ag- 
es of 40-50 yr and more. 
The red snapper growth models that we present are 
similar to those of earlier studies (Nelson and Manooch, 
1982; Szedlmayer and Shipp, 1994; Manooch and Potts, 
1997; Patterson, 1999) which did not produce separate 
models for the two sexes and variously applied weighted 
