254 
Abstract-Gray snapper, Lutjanus gri- 
seus , were sampled from recreational 
headboat and commercial landings along 
the east coast of Florida, 1994-97. Fish 
were weighed (g) and measured (total 
length, TL, in mm), and sagittal oto- 
liths were removed for aging. Marginal 
increment analysis on sectioned oto- 
liths (n=1243) confirmed annulus for- 
mation in June and July. The oldest fish 
examined was 24 years old and mea- 
sured 760 mm TL. Weight-length rela- 
tions were not significantly different by 
sex. Weight-length relations were sig- 
nificantly different (F= 39. 198, P<0.001, 
df=10,705) for fish measured from the 
headboat survey from 1982-97 between 
north Florida <W=8.4 x 10~ 9 x TL 3 08 , 
n=4034) and south Florida (W=5.45 x 
10 -9 x TL 315 , n=6670), where W = total 
weight (kg). The TL-otolith radius (OR) 
relationships were described by the fol- 
lowing equations: TL = (10.02 x OR) - 
52.98 (r 1 2 =0.90, u=519, north Florida), 
and TL = (9.90 x OR) - 91.68 (r 2 =0.78, 
n=724, south Florida). Mean lengths at 
age from back-calculations to the last 
annulus ranged from 121 mm at the end 
of age 1 to 740 mm at age 24 for north 
Florida, and 227 mm at age 2 to 495 mm 
at age 15 for south Florida. The von Ber- 
talanffy growth equations were L, = 7 17 x 
( l-e (— 017 {t + 0025)) ) for north Florida and 
L,=6 25 x (1 - e ( ~° 13 lf + 1 33)l ) for south 
Florida. Estimates of M ranged from 
0.14 to 0.43 for north Florida and from 
0.29 to 0.38 for south Florida. Estimates 
of Z averaged 0.34 for north Florida and 
0.95 for south Florida. Recruitment to 
the fisheries occurred between ages 5 
and 8 for north Florida and ages 4 and 
5 for south Florida. Estimates of F for 
gray snapper by area were 0. 16 for north 
Florida and 0.66 for south Florida. 
Manuscript accepted 16 November 2000. 
Fish. Bull. 99:254-265 (2001). 
Age, growth, and mortality of gray snapper, 
Lutjanus griseus, from the east coast of Florida 
Michael L. Burton 
Center for Coastal Fisheries and Habitat Research 
National Marine Fisheries Service, NOAA 
101 Pivers Island Rd. 
Beaufort, North Carolina 28516-9722 
E-mail address: Michael Burton@noaa.gov 
The gray snapper, Lutjanus griseus, 
is a moderate-size (to 8 kg) snapper 
(Lutjanidae) widely distributed in the 
western Atlantic from Florida through 
Brazil, including Bermuda, the Carib- 
bean and the northern Gulf of Mexico 
(Robins et ah, 1986). Juveniles have 
been reported from as far north as Mas- 
sachusetts (Sumner et ah, 1911), and 
transforming gray snapper larvae have 
been caught in ichthyoplankton sam- 
ples collected at Ocracoke and Oregon 
Inlets, North Carolina (Hettler and 
Barker, 1993). Adults are rarely caught 
in the fisheries of North Carolina; the 
larvae appear to be Gulf Stream exports 
and do not survive winter tempera- 
tures. Gray snapper occupy a variety of 
habitats during their life cycle. Adults 
are found near irregular, complex hab- 
itats, such as coral reefs, shipwrecks, 
rocky outcroppings and ledges, and 
other natural livebottom areas (Miller 
and Richards, 1980). Spawning occurs 
offshore, and eggs and larvae are trans- 
ported into estuarine, shallow seagrass, 
and mangrove nursery areas by favor- 
able currents. Larvae, juveniles, and 
smaller adults are found inshore in 
seagrass beds and around mangrove 
thickets, pilings, seawalls, and jetties. 
While they inhabit inshore areas, these 
younger fish are subject to fishing pres- 
sure from recreational fishermen. After 
moving offshore between the ages of 3 
and 4 (Rutherford et al., 1983), gray 
snapper are caught by headboat 1 and 
commercial fisheries. The primary gear 
used in all fisheries for gray snapper is 
vertical hook-and-line gear. 
Several investigators have conduct- 
ed age-growth studies of gray snapper, 
but most have been restricted by lim- 
ited geographic samples or gear types. 
Croker (1962), Starck and Schroeder 
(1970), and Rutherford et al. (1983) 
conducted age-growth studies on gray 
snapper using scales from limited areas 
in the Florida Keys and Florida Bay; all 
validated their aging techniques with 
marginal increment analysis. Manooch 
and Matheson (1981) aged otolith sec- 
tions of gray snapper from headboat 
landings along the entire east coast of 
Florida but did not validate their aging 
method. Johnson et al. (1994) described 
age and growth with fish collected from 
recreational and commercial landings 
from Ft. Pierce, Florida, through Loui- 
siana but failed to validate their aging 
method. 
The bulk of gray snapper landings 
in the U. S. South Atlantic (North Car- 
olina-Florida Keys) occurs in Florida. 
Combined landings of gray snapper 
from headboat, 2 private recreational 
and charterboat 3 and commercial 4 fish- 
eries of Florida’s east coast averaged 
493,895 kg annually between 1986 and 
1997. Average annual landings from the 
south Florida area (Ft. Pierce through 
the Dry Tortugas; 412,279 kg) were five 
times greater than those from north Flo- 
rida (Fernandina Beach through Sebas- 
tian; 81,616 kg). The species is highly 
1 A vessel for hire which charges each angler 
on a per-person, or “per-head” basis. 
2 South Atlantic Headboat Survey. 1998. 
Unpubl. data. Administered by National 
Marine Fisheries Service (NMFS), 101 Pivers 
Island Rd., Beaufort NC 28516-9722. 
3 Marine Recreational Fisheries Statistics 
Survey (MRFSS). 1998. Unpubl. data. 
Administered by NMFS, 1315 East-West 
Highway, Silver Spring, MD 20910. 
4 General Canvass Landings Survey. 1998. 
Unpubl. data. Administered by NMFS, 
Southeast Fisheries Science Center ( SEFSC ), 
75 Virginia Beach Dr., Miami, FL 33149. 
